kinetic studies of the oxidation of fatty acids · the oxidation of fatty acids is of fundacental...
TRANSCRIPT
Kinetic Studies of the Oxidation of Fatty Acids
Thesis Submitted For the Degree of DOCTOR OP PHILOSOPHY
In Chemistry
SHAKOOR MOHAMMAD KHAN
Department of Chemistry Aligarh Muslim University, Aligarh
December 1968
866
\7.m 1970
T866
ts&czyn ?OQ&.9$
? II B S I 3 Subcittod i n ful f i lment
of the requirements for the degree of DGCTOn OP P.HL0SOPHY
By
Shckoor Hohd. Khan
Chcnical Laboratories / i l icart **uolim University .Ali^arb.
D«cwrt>«r, I960*
A B S T n A C S
1
The oxidation of fa t ty acids i s of fundacental
importance in many processes such as th*» u t i l i za t ion of
fats in the aniraal body* drying o i l industry and in the
investigation of s t ructure of fatty acids . Besides, the
outstanding difference between chemical and blochenical
oxidation processes i s best exemplified by reference to
carboxyllc acids which can easily be oxidised to carbon
dioxide by l iv ing ce l l s f but are ine r t to oheolcal
oxidizing agents in neutral aqueous solution.
Chronic acid i s an extremely important oxidant in
both organic and inorganic cherai3try. I t has occupied
an equally important posit ion in the study of oxidation
mechanises. I t reacts almost a l l types of oxldiznfole
groups. The reactions often nay be controlled to yield
largely one product, and t h i s nalces chronic acid oxidation
a useful synthetic tool . Although the knowledge of the
raechanisms of chronic acid oxidation of organic compounds
i s fragmentary, yet as a resul t of pioneering work of
TVestheiiaer, Hocek, nibern and Waters, the nechanion of
soiae of the reactions io fair ly well understood. The
present work was carried out to elucidate the nechmism
of oxidation of lower f^tty acids by th i s oxidant.
2
The reaction rate r&a measured ae a function of
concentrations of chronic cxcid, substrates and hydropen
ions . In a l l the experiments the oxidant concentration
tms kept^low re la t ive to tiiose of substrates and hydrogen A
lone that the latter renalned essentially constant through
out eny single run. T,ven under these conditions, the
first order rate constants vary with changing chromic
aciS concentration,
?he order of the reaction with respect to each
fatty acid v?ao determined by varying the fatty acid
concentration and observing the effect on the rate keeping
chroiaic acid and sulphuric acid concentrations eonotant.
The plots of rate constants against substrate concentra
tions yielded straight lin<?o passing through the origin.
It indicatea that the ordef of the reaction with reference
to substrate is unityt and the self decomposition of
chronic acid is negligible under our experimental condi
tions.
The dependence of r#te constant on the hydrogen
ion concentration was studied in the sane way. The oxidant
and substrate concentration were kept constant and con
centration of hydrogen ion*? was varied naintainlnft the
ionic strength constant by usinnr sodium hydrogen sulphrte.
3
$he quotient* obtained by dividing peeudo first order
rata constants by hydrogen ion concentration varied from
run to run* But the quotients obtained by dividing firat
order rata oonatants by the square of hydrogen ion eon*
cent rati on remained reasonably eonatant showing oeeond
order dependence on aoldity«
The affoot of ionic strength on the ozld&tion
rat® wae observed by varying tha ionic strength by using
aodlne p©rohlorate# An overall acceleration with increas
ing ionio etrength wae observed* Tessperature dependence
of the raaotion rat© waa studied and thermodynamic nam-QJUCi
metere were calculated. The effect of acetic*,the final
oxidation product, on tha rata of oxidation m\& ncnoured
by adding various amounts of acetic aoid, to the reaction -
mixture. The rata constant* were found to increase with
increasing acetic aoid concentration*
Chronio aoid oxidation of fatty aoida wao alao
atudiad in tha presenoe of annganous and oerous lone. It
wao found that tha amount of onroaic aoid consumed in tha
abaanoa of Ma** or Co*** wae more than in tha presenoe
of thee* ions*
fhe influence of chain length on tha oxidation
rata of fatty acids wao Investigated* The observed order
or reaotivity followed tha sequence propionic < butyric <
Valeria* the effeot of branching wae also etudied and it
was found that isobatyrio and isovaleric aolda were aoro
rapidly oxidised then propionic and butyric aoi&a* Piveilc
acid wee nnaffooted* To determine the effect of phenyl
group on the oxidation rate* boneoio and phonyloootio
aeido were studied* Benzoic acid wee not oxidised out
the rate of oxidation of phcnylooetio acid wee ©uch higher
than that of propionic acid.
On the e&eie of aho^e reanXt© the tallowing rat© law
una obtained*
* ^ g | »)< m &£*Fett5r a c i f i J ^ r ^ £ V 7 * »
The meehanlea which i s oonaiatant with the above rate law
stay he written not
(1) HCrOj • ffl* ^ & * H0rOs • Hg0
B O H O
Ce) R - 0 ~ H * 0 « Or-oCti *lffi> R - C - 0 • Cr - OH • H*
COgH COgS
H O m C») » - c - o -Sir - OH £&5% R ~ e ~ 0 - C r ~ O H
I [ co^a oOgK
N o ^ OH OB OH / * I I I
(4) H - 0 - 0 * Or - 08 £&S% a - 0 • 0 - Cr - OH • H* OOgR COgS
5 o~n oa o OH
(5) R - C -rO- Cr - OH Bw*> R - C - COgH • Cr B 0 • H+
COgH OH
(6) H2Cr03 • HCP0 3 • R+ ffi?** 2 HgCr03
0 0 otf 0
(7 ) 8 ~ C T C - 0 T H + 0*Cr*-0H W * > R-C+ • C09 • H*CrO-
L> v_/ 2 3 3
0 0
(8 ) R - C* ' f a g | - > R - C - OH + B*
this i s to cert ify that the thes is
ent i t led "Kinetic studies of the oxidation of
fat ty acida% io the original worlc of Kr. Shafcoor
Hond. Khan and i o suitable for submission for the
degree of Ph.D.
Dr. A. Aaiu Khm
ACKHOrLEBOBOTOT?
I wish to oxpreos qy grati tude to Br, A. Adz
Khan for hio supervision and also to Br. tt.A. Beg for
the valuable suggestiono regarding the selection of the
problecu I an thankful to Prof. A.R. Kidwai and Br. S.H.
Paslur Rahiaan for providing neceaacry f a c i l i t i e s . Shanks
are also due to Br. U. Rahman rmd Br. ELS. Ahmad for
the i r helpful suggeotiono during writing of the tfaesia.
fhe help of Br. Piros Ahmad and other raenfcera of Physical
Section lo acknowledged grateful ly .
Shakoor Hohd. Khan
C 0 9 T B R 7 S
CHAPTER I .
General Introduction
CHAPTKR II.
Kinetics of oxidation of normal chain fa t ty adds*
OHAP?BR i n .
Kinetics of oxidation of branched chain fatty acids.
CHAPTER IV.
Kinet ics of ostldation of phenylocet lc ac id .
CrtAPTER V.
Discussion.
C H A P T E B I
G,:JH*IAL m?do:$c?2Qn
TUG oxidation of fatty acids io one of the i .rjortont
reactions in ehoDlstry of fato cmcl o l i o . !?hio io of funuie-
E0Ktol ittportuneo i n sony srooessen such as u t i l i s a t i on of
fs to in tft© aaicyal body? in fcbo $rying of f l lcc* 4B tUo
EGnnfnottaro of various product© of drying o i l industry ana
in the Investigations of the s t ructure of fatty coidrt and
the i r derivatives,,
Ao rould bo expected, the octuratcd fatty ecido
sre coat rooiotant to chemical oj&dotion. Only the oyidcnfeo
which can stteeft saturated paraffino ore able to oridico
fatty acido. 7ho end pro&ueto are nunorouo end diverse
dcpendiiir upon the oxitlcnt &n<l the conditions of ori. 'ation
such as teapcreture, concentration» oolvont, period of
oxidation end cr to lyc t . ?ho ojd.io.tion ray nc&o tnroe/?h
o ocrico of Intercicdlfttoe or &ay di rec t ly 1>c eoav^rtetf to
specific en<3 proSuetc. In nrjay instances tho i n i t i a l oxidtv-
tion products are so t r e n d tory that t he i r fornetlon i s
only a matt or of ouoculotion. Uir.ilrr othrr complications
t ry ".rise end thr> invest!«jntion of oxlJetlon nc*e?i&nis& lo#
tfarrofo-e, frnu^ht c i th various a i f f i cu l t i eo .
2
Inopite of the above facte* sorse inveotirntore have
attcnpted to study the nechr.nl on, the nature of the i n t e r
mediates tm& the cn<3 products of oxidation of fat ty aolde
by different omldlarlnn agents.
Son© oxidanto are niijhly specif ic i n the i r reac
t i v i t y chi le others arc quite nenoral in both reac t iv i ty
end application* fhuo* potaaoiuo peiTsaneanate, ozone,
and organic peroeids arc uidrly used in invcotinatinfl the
s tructure of unsaturated fatty acids , whereas lead t e t r a
acetate and periodic acid are r e s t r i c t ed to tfeo cleavage
of poXybydroxylatcd or other pa r t i a l l y oaddlccd fatty acidn
of certain s t ructural types* A nucbor of end. fonts do not
possess any special n a r l t in the invest igat ion of fat ty
acido and consequently, they have not eono into fencral
uoe# A few oxidanto l i ke sulphuric and n i t r i c acids t?hich
are of eo^e value in certain indus t r ia l p«*occooest are
not; largely of hlotor ical i n t e re s t in the elucidation of
the s t ructure of fatty aoida.
Chrosic acid i s one of the few strong oxidants
which has been widely used and reacts tslth etlcoot a l l
tyt)cs of oxidiorble groune. I t has re-mlnrly been used
for ft«ll over a century both in volumetric rnalysic and
in synthetic and dcrradative organic cheaistry* /Jthoupji
the knowledge of mechanists of chroasic acia oxidation of
3
orgimio compounds i s only frac»pntGry» yet no a roeult
of pioneering ssork of restheinor* Hocck and Dto:?ort the
Ecehaniaia of socio of th© reactions io fair ly well uMes-
stood* A review of the l i t e r a t u r e on the chronic ooifl
oxlfintlon of various functional grouo© io given below*
the. Caroiaic acid oxidation of alcohols Hon boon otuiiea
eatteneively because of i t a on^or use in synthetic ehenlr.try*
Prleary alcohols give al<ler.ydee an<3 acldo in quanti tat ive
yields r;Mle Ketones or© obtained froo secondary alcohol a.
fftcj reaction i s loos satisfactory in prosenco of eaoily groups.
oxidiBablc functionalA Tho diff icul ty encountered lo due
to tbo poaoibil i ty vE the cleave^© reaction* Phenyl t o r t -
butyl csrbinolt for cncanple» gives beneeltiefcyao tm& t e r t -
butyl alcohol as cle&vsafje products accompanied by a enaller
quantity of to.© expected ketone.
OH 0
c6tt5 - c - c (cn3)3 ^g - > c ^ - c - c <cn3)3 • H c6KeGno • (c:i3)3cca
?feenylelkyl carbinolo r ive generally large ccounto of
olcavc.^c product©. eatheiner and co-rrorkcra * obtained
C* clcavr.ro s?ith phenyl loopropy1 corbinol and 60,* cleevcro
irith phenyl te r t -buty l carblnol. Cuch typos of clcavare
reactions ©re &nown to occur in cany other enrbinole * *
4
She cleavage reaction con be ©lininated by addition of
©anganouo ions .
Boldest and co-worker©5 found that the oiddation of
oeeondary alcohols in acetone ncdiuB proceeded r.or© rapidly
than %n acetic acid. One of the advantages ??ae that
because of the large excess of acetone In the former eaoc
tho ketone produced t?ao protected against further oxide*
t ion. I»at©r on, Botss&n et a l ; found that pctasalun
diehroiaste and chrooluta tr ioxide In acet ic acid *?ere tho
effective reagents for the oxidation of secondary alcohols.
Ficoer7 oxidised choleetanol to eholootanono in good yield
velng diehronate in acet ic acid* fhe diff icul ty encountered
in tho oxidation of primary and secondary alcohola rma
overcome bj Oarett8 who visualised that pyridine-ehrociiun
tr ioxlde coErple? o i rh t not oxidise tho other functional
groups* ffeo reagent has been uee& successfully in the 9
oxidation of a eroup of nteroidal aloonolo. Boltus
eatolored tho u t i l i t y of th i s reagent for the oxidation
of a ler#e nucbor of alcohols*
T>rinary alcohols are oxidised by chronic acid to
aldehydes which ore further oxidised to the correonondinr
carbox;*lic acids . The poor yield of aldehyde have been
at t r ibuted to the side reaction betceen aldehyde and
unreacted alcohol to tflve hetiacetnl «?hich say further be
5
oxidised to eater #
n m2 oa - •»'"'"> a cuo n I
B C H „ 0 i I • HCIIO •' •• ••«* R %. C - O C H « B
* v:""""""" J 2 on
H
B - C - 0C3„a + C r ^ n"" "^> ]} • C - 0CS393 I II 2
oil o
Koter fornetion ie diolnlcned by sveepln^'off aldehyde
out of the reaction oixture with a strain of carbon dioxide
or nitrorron. Opponotior sad Otoerraueh*1 reported for the
first ti&o that tert-butyl ebronate in netroleun ether
was n rcissr&abl© oxidant for tho oxidation of prinary
alcohols to aldehydes in excellent yield©, Hexctdeonnolff
for esABDlOt cao converted to hexadecimal in 80-85"*' yield*
garaalol to eer&nisl in 85* yf rid and boncyl alcohol to
tauald.**. in 94.: y l o i a " . „ teoD ^ t h o t 6 h i B
reagent reacted by n rapid trano-esterific^tion *?ith
prinary end secondary alcoholQ« This oaterifi cation and
i t s reverse usually involved electronpeir displacements
et tiie chrociun nton i .r# acyl-oxyren bend flonion.
As n result of oytcnoive 3tudiea on the ehrosie
eel ! oxidation of nleoholo, featbeic:or15 proposed a rate XOM>
6
tjhich xm& found to to© appl icable t o a l l the pr icary and
secondary alcohol© otudiod eo £ar# frmtso * observed
tha t i t waa poss ib le t o prepare e s t e r s of chronic acid
*?ith p r ioary and secondary alcobolo and these were
decoopoaed toy pyr id ine to give tho corresponding earbonyl
conpoundo according to the follosdLag scheiEes
, 3
m% ~ c • o
H B,"*
CH3 - C « 0 • <c«3>2 teW G r 0 g + H B*
On t h i s bas i s tToatheiccr proposed tha t the oxidat ion
of pr ieary and oeeoiidary a lcohols proceeded via the acid
chro&ate e a t e r .
BgCUO.1 • HCrOj • B*
EgGlIO CrO^a * H*
rtg<r-:o crD3:i
The data on the t&netico en<3 i so tope effect for iaopropyl
a lcohol oxidat ion could be explained s a t i s f a c t o r i l y by t he
0 II Cr II 0
» 0 » C - C£L ^
- ^ HgCHO CrO^l • llgO
• ^ * KgCHO Cr03llg k
&^v I2„C « 0 * Cr' X?
fc 2 ^ ngC » 0 • Cr IV
?
PA
above reaction sequence* Cloning' aloo 3G)»onfitrate<S tfcte
forcotion of coifi cturacnte «s ter in the reaction oolution.
t»ntcr on,the intorscfiiGcy of the enroaie o d d cuter ros
confined by on investigation of the oxidation of s t e r l -
colly sintered olcofcoi 3^£3-aiocoto:Ky-6£-fayaro:Ky-18)&.;
IS-olconoa » Altno«i£a tnr forest ion of eotoU' 00 on
i n t e r a o s i t t c hs© Doen confirnco' but i t s conversion to
products i s a f i l l on unsett le^ pro©len# General b&oe
cf talyale *>y pyriaine* ao ey^osefi or iginal ly , ^a$ confuted
l a t e r on 2 6* 2 7 .
?*ooo& aaa ITrupiefea obovred thot the lcimrltlMB of
tho rcto constant i s Xinoorly fiepondsst upon the Hnnr.ett*a
acidi ty function H • "'hey mceeotco1 thot tnc oxidation
orooecded by a tsoloculer cyclic ©leotron owiton* involving
jcolecular UpCrQ^ a t low a c i d i t i e s , and a nrotonricd epecies
Il3Gr04* or HCrOg4, a t nlrfeor ee iCi t ies .
GH3 u - <n
03- \ 3 Oil
Vhis cyolio aeehAjoloCi &oy provides G ncre ost isfretory
explanation of the rel&tire ra tes of oFidetioo of pora-
onbotitutei? 1-phenylnthe.nolsj the order of react ivi ty *>*u*a
« 5 ^
8 IiO C ^ ~ ^ 1
^*SU"€» +
Cr
8
28 Plectron-donet ing oubstitwent© favoured oxidat ion *
Grahao end Steetheitaer eloo concede t h a t i n very otrong
ac id a cyc l i c mechanics msch as above Dny otjercto*
Chrosie acid oxidat ion of l a rge rnacber of organic
conpotinda oeens to proceed by the schene*
C r ^ W j • S — ^ > CrCIV) + F
CrCIV) • Or{n) ^ > 2 Cr(?)
2Cr(V) * 2S ~ ^ - 2 C r ( i n ) <• HP,
Hcnoef tho oxidat ion ??ith chronic acid i s i n fac t an
os idn t ion by C5r(V). ?hio sroo concluded fron the fac t
t h a t 67^ of cleavcg© products (benaaldehyde end t e r t -
bu ty l a lcohol) wore obtained froa the onrooie ncid oxida
t i o n of phony l - t e r t -bu ty l eorbinol end tho r e m i n d e r wm
the expected ketone* 2ho degree of cleavage BGS ©tappreeaed
by eddi t ion of corona and mengenoue i o n s , i nd i ca t i ng thn t
cleavage «?ae affected by Cr(lV) or Cr(V> and not by Cr(VI}»
tho cleavage reac t ion doe© not involve the hydroj^n a t tached
to the react ion cen t r e ao i e i nd i ca t ed by the lack of
i s o t o n i c f rac t iona t ion i n the competi t ive oxidntion of
l ebc l l ed and unlebolled alcohols* The data eucgestttvo 30 poss ib le taeohftniecuB •
9
i. c€ng - CH - C ( C H 3 ) 3 • crv — ^ c^i5 - ca - C(CH3)3-
OH 0 * CrV
H
H20
OH 0 «* CrV
^-C^RgCBO * (CH3)3 C* —a-^- OgRgCHO • (CH3)g CO!!
Lack of ojfygea-13 in th© te r t -bu ty l alcohol fornod in
the cleara&e of tho labelled alcohol indicates the unlikely-
hood of GochEiilonCl)* techenisn (2) \?ao oupported by th©
oboervation that phenyl aprocacphyX carbinol t?ao oxidised 31 tdthout eleavege •
Oa&detlon of t e r t i a ry alcohols i o core d i f f i cu l t
than that of primary or occondary alcoholo* but can be
affected in th© presence of sulphuric acid. She otudleo
of Soger end Pocek on the Kocheniec of oxidation of
t e r t i a ry alcoholc showed that th© reaction i s f i r s t order
with reepeot to alcohol but independent of the concentra
t ion of the oxidant. I t indicated that an olefin wao
10
fonaed slowly which vmo then repidly oxidised to a ketone.
34 Slack and l a t e r e for tho f i r s t t ine investigated
the chrotsie acid oxidation of diolo* £hey obeerved that
the eloavoge of 2,5-butylcne glycol (20-30$) srae nore
than that of ethylene glycol (&»££)• Chatter^se and
rulther^ee carried out a dotailed inveotigstlon end
poetulnted kinet ic ra te lens for different glycols, nataely
for ethylene glycol and plnecol tho r a t e lass tsere as under* i
v » k ^ d i o l j ^ c r o j j ^ * y »
I t ©eeno that tco reaction course© are possible. In the
f i r s t case normal ©jddation occurs #lviaf: an e<~hydro*y~
carbonyl compound, which m$ be further oxidiaed» In the
eocene!, cleavage of carbon-carbon bond occurs*
Cheng and Cestheloer aloo otudied the chronic
acid oxidation of plnacol and found a solvent ieotope
effect k s 0 /kg 0 » £•?• They observed that conomethyl
ether of p inned was oxidiced very slot?ly» I t indicates
that oaofgen-nydrogen bond cleavage doee not occur in the
ra te determining otep and cyclic chronate eater i e probably
the intermediate* This es ter i© decomposed to the observed
products in a Banner oini lnr to that suggested for lead
11
te t raaceta te and periodic acid •
B0C - OH A B„ - 0 » 0-^ . 0 8 1 • HCrO* + H* > H | Or ^ • ~*>
H2C - OH Bg * C - 0 ' ^ 0
E„C « 0
agc « o
Cyclic chrostat© formation mechanise was further supported
by the observation that ci8~it2~din©thyl»l»2-oyclepenta>-
nedlol was oxidised 1?#0O0 tie©© -faster than i t s t rans
iaoaer » fhe large difference in the ra te of oxidation
could not be explained oy a non-cyclic ©oehanion, ?he
ra te of increase of olaavaii© «*i*h the oethyl subst i tu t ion
t?ae explained mt the asaucotica that alfcyl oubsti tution
s tabi l i sed the activated cotsplex for the decoapositlon of
the cyclic chrofsnte eator .
Although considerable trork has been done on the
chronic acid oxidation of diolo yet the reason for a change
in saeGhanlaia with inereaoinr methyl subst i tut ion la not yet
clear* ^loo the a b i l i t y of chromic acid to effect both
normal oxidation and cleavage la not well understood.
Aldchydea are tha intermediate products in chronic acid oxidation of prissary alcohols to the corrvapentflng
12
oarboxylie acids . Buccal # for the f i r a t tin© studied
th© oxidation of aronmtic aldehydes in acet ic ecid-oulphuric
acid Ejcdiunu He showed that the reaction wee f l ro t order
in aldehyde end In Cr(V2) end that the electron withdrawing
groups fac i l i t a ted the reaction* He, however* did not
otiiriy the effect of sulphuric acid on the ra te of the 41
reaction* riherg and Kil l * carried out a detailed kinet ic
study of oxidation of beasaldoayde and formulated a ro te
las? an
(in aqueoue solution)«
and IME £"H0aoJ^HCrdJJ r H0 ( i n ace t ie a c ldh
On the basis of t he e l o i l a n t y i n ra te las? and leotopo
effect In the oxidation of bmsaiaehyde by pernangenote42
and by cfarosalc add* they suggested tho following ©echnnlari
BCrOj * B* • ...MM.x H2Cr04
0 OH II i
C 6 % - C • H • H g C r 0 4 fr C6Hg - C - 0 CrO^R I II
m
C6HS ~ C - OCr05H > C^Ig - C » 0 • CtitV) ,
13
?he jacchanlora la oiE&lar to that proposed by Eootheiaer
for the ieopropyl alcohol*6*
Oxidation of a l ipha t ic aldehydes has not received
EJttch attention* However* the ra te lawo found l a soise
eaaea are quite a io i l a r to those obtained for tho aroiastie
aldehydeo. She ra te lap for forealdehyde44*4^ hae been
sJiorm to be
Kenp and l a t e r e found that fcinctic loo tope effect and
energy of activation decreased in the solutiono of bi*?h
acidi ty , ffcey euggested that i t was due to tho effect of
acid concentration on tfa© reaction© of Cr(I?> and Cr{VK
At higher ac id i t i e s tho r a t i o Or(I?)/Cr(¥X) tnereeoci
more rapidly, and the oslNation caa effected mainly
e i ther by Cr(llf) or Gr(tf). Chaterjee4 9 deternlned the
induction factor aa 0«5 «hioh indicates that CrClV) was
the product in the oxidations by CrCVXK
A number of s tab le hydrates of aldehydes are
teotsn • I t was reported by I'erss and r ,otere * that
in the oxidation of foraaldehyde* the hydratod fore of
aldehyde waa the reacting epeoiea* The vclue of P , for
aromatic aldehydes i a • 1*02 and that for a l iphat ic
14
aldehyde i© ~1«2* fh© difference betrcen the reaction
conotante for the two types of aldehydea io approximately
tho reaction constant for the hydration equilibrium for
the aronatic aldehyde©* fhuo» i f the arocntio aldehydes or©
aeouoed to roaet i n the hydrated fom, the f value for
the reaction would bo about «*JLcorresponding to the value
obtained in the oxiaation of a l iphat ic aldehydee^aleohola*
?bc aesunption that the reaction involves tho hydrate of
the aldehyde io in agreesent with the r e su l t obtained by
varying the water content of the ace t ic acid - trater
nixturec*
fhe isain problem in the oxidation of aldehydes
by chroisic ocid i s t o determine whether i t l a a one
electron or a two electron proceoe# TTeetheieer need
induced oxidation as a diagnostic tool to solve the
problen. Clberj* end Eichardoon reported a very i n t e r e s t
ing non-feinetic example to detert&ne whether Cr(JV) or
Cr(V) «ras the active intermediate, ffibey observed that
triphenylaoetaldehyde w&a oxidised by chronic aeid to
&ive approximately one th i rd tr i^henylaeet lc acid and two
thi rds triphenyloarbinol and carbon monoxide, the eetcr
nechanisn nipht be expected to clva e i ther tr iphenylacetic
acid or triphenylcarbinol and formic acid.
15
0 OH
( 0 ^ l g ) 3 CC-H • RCrOj • H* ^ »••>» ( C ^ g ) g O-C - OOrOgS
H
m OH I I
(CgS^g 0-c-o-cro3H ••• »*> ( c 6 % ) 3 c - c - o • c?(iv) H
Or OH 0
I + II
<*y%)3 c - c * o * cro^a »•• > * c #s*3 c * H * c ~ m *Cj*3nr* H
Hydride or hydrogen afcon a b s t r a e t i o n t tKmeverg olgfet l ead
t o t r ipt jeaylcarbiaol and carbon nonoxidc. 0 0
( C ^ l 5 ) 3 0 - C * H • Cr ? -—> (Cg85)g C - C+* Cr*1 1
0
0 r 0 0
(CgHg)3 C - C - H • CrV • > ^ V V a C - C '* Cr1*
0
( C 6 H 5 ) 3 c - c > * c e V 3 c • co
0
(Q^)C\ H2Cr04 ^ (C 6 H s ) j 0 - 0 - Or - <X1
on
> CC6H&)3 C011 • Cr ?
16
?ho product ®tu&y so res t© that on© thi rd of tho reaction
proceed® iri© the ector Deoheale» end two th i rds isdLo ei ther
hy&si&e ©©©traction or hf flrogoa atoa abstraction ceobanlBi-
ffeio clearly iadicotoa that Cr{V) i s the sioin rceet lnc
en eel co i s the oaddntien of aldehyde©}* Imi in, part tho
reaction proeeede with CrCIT)*
The 03& Nation of i'otonos by chronic oeiOi ceo f i r s t
studied by Pe t i t • lie found that tho os&dafloa ra te
increased with InereacsifSf* oiicAn length froa acetone to
hcptyl eethyl ketone t and tho reaction took ploce through
en cnelication ooeboaioD* $cedo, end farasn derrick out
the oxidation of eycloheaaneno in preoeaee of 1101« HQUO^
and 3C104 cmd cuccesteft a ooehanieH uhieh involved the
onelisetion of csrclohoEenonet addition of two colceulcs
of HCrOT, the fission of tho double eond end osirtation to
adiple edvl of the reoul t inr ddehydc* L i t t l e r rnd
"store 3 etttdleA tho itineties of oxidation of cycXohexenono
by three electron, two electron end on© electron oxidents
and concluded th*it two electron oxidant attaeiied the estel
for© while one electron oxidant nttac&od tho feete for© of
the eubiitrate. But tho attack of chronic acid (3 electron
oxidant) on tho cyclohcxcaon© remitted undecided, T*ie ra te
controlling ©top coold bo the attack of cferoislc cold <m the
<?o«ble bona of enol fom or i t could bo the decomposition
17
of th© chronic aeid «©ter of the enol form* But ea the
refce of oxidation of cyelonoxanonG was slower than i t s
reto of enoiication ot the sane acidity i t ooulS not be
concluded whether th© fceto or enol foro rcao attacked* I t
racraly indicated that tiso tranoit ion s t a t e of tho r&to
deter^inlne process involved a ketone tsolooule and a
ehroaSe aoid nolooule.
Isidore and Gatcls©64 eufijeatod too poss ib i l i ty of
the fro© radios! noehasiosi for the oxidation of deo^boncoln
by chronic acid on the baeis of the i r observation that 8:*
bidooyl WHO obtained slon^ tdtfa the expoetod bcnsi l .
KoeoJtSS also visual!cod the formation of eoGso fros radicals
in tso ©j&datlon of oyclohaxamonc*
fhe oi&dation of eryl alfeanto i s par t icular ly
useful fron synthetic point of view because of the forca-
tion of aryl earbosqrlic acid© end arorsotic aldehydes. I t
i s also helpful in dotercininr ^be orientat ion of nl&yl
grouo© attached to the aroootlc nucleus* r.5en£scne io
rosiotrnt to oxidation but ©jpossatic ©olyoyellc and iietoro-
cyclic S^rccarboaa 6 7 - 5 9 are eaelly ozldicea to - luinonc.
?he order of the react iv i ty of these eormounds depends
upon the i r electron ava i l ab i l i ty and i s wholly consistant
with the attack by a cation HCrO * Electron donating
18
j^roupe have been found to aes ie t the rioft destruction,
*h« alkyl group of an alltyl bencone, rena*dlG8e
of i t o length, i s fincHy ©xidiced to earbosyl group with
the formtlon of on srooctie carboxyllc aoid« Shuaj
toluene fdves benzoic acid and n © p~sylenea r*ve the
corresponding dlcarfcos^lic acids" . r i t l i longer chains
the i n i t i a l aitacli i s at the e<«*pooition to the arotsatl©
r ing, Shun, fron the prodaeto obtained in the osidation,
the nature of tho al&yl groups attached to the ting can
be detonsiiied. Polynuclear hydrocarbons are oxidised in
the e&ce saosner* r a t e r s obtained bensephenone in good
yields frora the chrocie acid oxidation of diphcnylnGthane.
7he 03dLdf*tioti of anthracene end fluorenc end the i r n i t r e -
honologueo wee studied by Gftita and Afeinoto e&o found
thet electron withdrawn* group© (n i t re ) retarded the
react ion. I t trae noted that t r i a r y l eubetitutod nethanee
f*ave the corresponding t e r t i a ry alcohol© which under
vigorous conditiono led to the breakdown of ono aryl group
tslta the for&ation of diary! ketone©*
BrandenberiTer and co-sror&ers reported that rtnc
oxidation was competitive with the side chain oxidation
in the ehronio acid oxittation of alfcyl bensoneo under
Euhn-Koth conditions and that the a&ount of ring oxida
tion increased with increasing o d d concentration* In
19
order to suppress the attack on the arooctic nucleus and
to effect the oxidotion of oldc chain oalyf tfe© wee of
potasuios diclarojs&te in isaior s t elevated toepctrcture was
«aed t&ts rea^GUt to obtain
a auober of orocsatic oono and ttolycajrbexylie eeido fron
alley 1 a d no oxidation,
53ie f i ro t detailed otady of the oxidation of aryl
albcuoo tilth c&roeie acid woo reported by Slnelx *snd Enters •
2&©y studied the os&dotioit of dipftcmylDetboJte and tr iphcnyl-
nethene in p l a c i d acet ic acid. I t «©o observed tfest the
order of tbe reaction 0lt*s reooect to chrocitio t r i oxide
in the oxidation of diph<29yXDot!s*m© ©nd fcriphenyloetfieno
*?&9 tne and ©no rcsoeetivelyt while tho order d t h rospoct
to hydrocarbon© trso on© in both tfte caoeo* ?hpy sloo
rnportrd that chrociun acctocfaronitc f*Cr• (ncrO^Xosorjig)^^
foraod i s tuo reaction retarded tlio r a t e . In th© oxidation
of toluenes m& r inc oubsi i ta te i toluenes » the order with
reepeot to tfto eabetrate «%o one but tso with roopoct to
chrociuD trloxide* t-ater on» those at'toics roro extended
to nctoistfc&l ena end fluorsnen* ?he oboerved ra tes s a t i s
fied the previous ra te equation. I t t'©et therefore,,
concluded that tno oncse cceluinlan woe op err tin;*: In then©
oxidations* i»e . tiie attack of two coleculce of chrooiun
Irio&ide on one molecule of the oubetreto.
20
Pirone studied the oxidation of di phony Itjothsne
aa& other cospcnmSe i a 98?* acet ic eoid using mineral aoi$
e.o. ca ta lys t . Product emslysie sfeowed the presence of
PhgCIfp anS ?bgCO« $he proposed ra te equation vm
67
©Herd h 0 i o the Uacsett acidity function . 2be value of
tbe kinet ic isotope effect t?ao found to be 6«4 at
30 °C m& i t was note& that the electron relenslns pronto
fac i l i ta ted toe reaction concretely. On the busi® of
these deta i t r,m concluded that the i n i t i o ! otop no.© the
abetraction of ay<2ropen a ton i?ith the formation of PbgCll*
radical rblcn wae further oxidiced to Ph CO He,
Ghrooio acid oxidation of ol&enee lea&e to carbon-
corbon bond, fission a t tbe olefinic l ink with the fonsstion
21
of a variety of products* The reaction io eisployed in
tlarbier*wl0le»d degradation and in the oxidation of t e t r a -
pnenylethylene©. 2etrapaeaylethylen«8°^ ° with OTtaJlor
aaounia of chronic acid give the correspond!nr epoxides
^hi le bensophenonc ie obtained trith larger anounts.
— 1 3 - ^ ^ C C
€ 6 0g
C r 0 3 ^
0 ^ HOAC « „ ^ \ C^5 S A
HOAC ° ° ° °
2h© study of oirldation of cany oteroidat double
bondo iraggoete that the i n i t i a l compound foriaed in th©
reaction *7ith chro&ie acid (cha to iw it© otructtire)
flccocpooo to five the epossl de end t h e ketol in the tco
©operate reactionaj and a t Icaat pert of feetol i s foroed
direct ly end not via tn© epoxide/ Barbior-^i el and degra
de t i on • " lo of great irnortenc© in the degrndation
end not i f icat ion of s te ro ids . GO
ntrij, cog c.i3 • c6ns K- ir — > rm2 - c - ( c ^ ) £ —~> CrO*
tlSH « C(C6Iig)g £ > nQOn b ° * 30A2 ^
The oxidation of alkenes by chronic acid in
22
oulphurtc acid ic different fron that in acet ic acid
eediucu fiic i n i t i a l reaction osy be the eene in the ts?o
cases but the u l t ioe te product© are different . neerrcoRe-
nent i e possible in the forcer solvent . Hickinbottom 74 7fi
and Stood • ©uggestcd that an epoxide might be en i n t e r
mediate in thooe reaetio&e oftd the foroetion of the
rearrnn.TODent products could be accounted for by essucins
on acid catalyzed pinacolc typo reerranj^eoente of the
intercediato epoxide* Further, Hickinbotton end co-norkere
eufjsested that the i n i t i a l etep involved an e lee t rophl l ie
addition of SigCrO^ to the double bond foroin^ tm i n t e r
mediate which oi/rhfc deconpooe to epoxide by looe of Cr(!V)f
or i t ol£ht lead direct ly to the roarrangenent producte
without involving the epoxide* Uhe hypothoslo rcno however f 77
diecar&ed by :>eioo end Soensic who found that in the
oxidation of 1-tsethyl fenchene with chronic acid the
reoxran^eisent product fonchene t?ae obtained in very l i t t l e
p.nount (6f)« 7B
I t appears iron Hi cfcinbottoia* © atudiee tfeot an
electron pair io donated by the olefin to 0 * Cr bond
producing en in temedle tc «?hich rapidly reacts with water
to yield the conjugated acitl of en epoxide*
23
2 - II 0
Hg0 - OTR - 0 - Or » 0 II
0
I V £•>- t?jj - cim - m * (HCrC)
Is2 Biol formtloa i s cer ta inly a socoa&ary reaction as
e$>03tido& o©& fes isolated In hlg& yields fro® olefins by
tiae of chrorsiuis triostid© l a acet ic enhydrid€ diluted with
c&rboa dieulphlde. £eias and 2s©tHKig determined that
the oxidation of olefins by ehxosic scid tras of f i r s t
order sirlth. respect to hoth olefin and chroraic eol4« They
proposed that carbonta© ion formation provided a nor©
sat isfactory explanation than th« cyclic intermediate.
a*c » can * 0 « cr - oa — — RgC - CHE ~ 0 - Cr « 0
0 on * Oil
I
1 0
\ i
o x
i i
0
fir
on
2he above ceeh&alsn cm be ppplied to the oi l Nation of
conjwated dienes ohioh ©osily yield keto3© •
ft detailed study of oxidation of hydrocarbons by
24
chrocie acid has been carried out by Boce& end co-workers,
fhey determined the re la t ive rateo of oyidntion of prieary,
eeeondary end t e r t i a ry carbon-hydrogen bonds as l*ilOs?000.
I t i s seen that zsethyl group i s addon oxidised* Jfee
oxidation of oecondary carbon-hydrogen bond yields ketones
trhich are rapidly oxidised by chro&ic acid. The yield of
the lietone, therefore, depends upon the re la t ive ratfce of
oxidation of ketone cad hytroearbon end upon the ab i l i ty
of the wor&er to eheele the reaction a t the point of oaadsua Q « OR
yield of ketone. In eooe eases , * a reasonable yield of
ketone i s obtained where I t a eaali station beccnes d i f f i cu l t .
Tertiary carbon-hydrogen bond i s oxidised to corresponding
te r t i a ry alcohol, JJ-Utbyl-S-pentenol (502 yield) lo 86,8?
obtained fro© the ehronie acid oxidation of 3-ethylpentane. ttoeek also showed thet i-oetaylcyelohexanol re© o os^or intermediate in the os&dntion of ©ethylcyclohex&ne.
fhe influence of ctrueture on the ra te of oxidation
of hydrocarbon© ras olao otudied by fiocel: and co-workere"^^
They showed thet en increase in the chain length c rue eel a
enell increase in the oxidation r a t e . Ster ic hindrance
was found to effect the reaction rat© in hirhly branched
Ciein hydrocarbons. Phenyl ©ubotitution a t the reaction
e i t e au£cented the oxidation r a t e .
25
ft conoidorable number of date on the rechenioa of
oxidation of alk&noo by chronic ncid in aqueous acet ic
acid ant! retiBOaBMy large k ine t ic iootope effect indicate
thot the rat© determining step i o the cleavage of carbon-80—83 Hydrogen bond. 2ho kinet ic r a t e law nae been &kmm
to be v «t k ^"nlkmQjF^PQzQftJP &0» l in^ tB<J hydride
abstraction EctohaaisK,
hoo been popula ted , tat ~iberr « * r i o o n t h a l ^ pat
forward er^uiaonts apei&et tne above oeehanisn and suggested
tho ooaoibil i ty of hydrogen ©ton cbotrection-oeclianioG.
£*!I3C* fi3«i%7 ~> n 5 - 0 - 0 - Cr(I7)
R3 - C-O-CrCl?) • ""'>> H3C0H • Cr(X7).
In order to explain tne re&rranc-ecent in the
oxidation of neohexr;ne» the forrat ion of or^rnic ccide
in tho preeence of aside ion nnd enonsouo react iv i ty of
the ter t inry hydrowne* Tioeek suffjeoted t h r t the solvent-
C .TO trap pod-radical forred in tho i n i t i a l otep should be
written an resonance hybrid of the s t ructures
C%G'GvvJ <£—> ^fr C CrAV_7
26
Tfa© resonance Hybrid could e i ther decompose* to tb«
carteonioB i<m or aa&er-r© eosabltiatloi* to giv© the CrClir)
eo*#r whlafti l a as© geiHKttlly regar^e*! a® the- reaction
intornodinte les&in,* to alcohol fozB&tloo* fbo csrboaiuD
Ion way fee forced by tb® electron transfer process or by
a cleavage reasfcioa of 0r{XY) eotor with carbon oxygen
boa6« I t I s 41f fietilt to decide bft??e«n the tew poss i
b i l i t i e s .
Ghrosie aoid boo be©« wsefi in the oxidatloa of
saturated, anoetttrateftt hydroxy, fcoto and other types of
&,ei£» to produce a variety of oxid&tiOA pr©3»eto 6epen41n<»
upon the reaction conditions sod the nature of subs t ra tes .
Host of the published «?©rls describes tbo us® of th i s
©xii@i5t for ottolyileel purposes iti the ele&vct/fo of fatty
©el<S ohaln# I t ha© also boon applied to the disruptive
©uri Nation of tmoattiratod aoiics an<s to the further oxi^atloa
of pa r t i a l ly oxldiued products such as hydroxy an<2 Jsoto
adds* However, l i t t l e wotk ftao been «lone on tbo controlled
and etcpriae oxidation of uaoaturated fatty a d as r l t h
chromic acid. a@ d i f f i cu l t i e s encountered l a ttsis fcin€
of stutiy ere that the lorge ntusbor of competitive reactions
tafce oloee tm® the iBterneoifst© oxidation pro&acto are
core reafiily oxisiisefi thm tfco s t a r t ing notarial* The
cajor reaction of saturates fa t ty ©olds l e en oxidative
27
degradation, The oxidation taken place i n i t i a l l y a t
<=><»earboa atOB» Thia i s evidenced by the large amotmt
of shorter chain acids which have been found ason^ the
oxidation products.
Snethlag® otadicd the oxidation of oxalic acid
by chronic acid in concentrated sulphuric acid Dedluo.
He ohaorved that the order of the reaction with respect
to chrooic acid varied between 1 - l .S while that of
oxalic acid between 1-2, Gasrlcnis ra te was found at 70$
anlphnrie acid concentration, t»ater on, /tsnoroo and go
Saga found that only 3 0 P of oxalic acid was oxldloed
In a l l caeca* Sono chronie ccid remained unchanged tsrhea
the reaction stopped oven a t the boil ing point* faey
postulated that a heat s table eomlox /"erCCgO^HBgO^.J^*
•miB forced ao en intermediate wnloh was converted to
^f*0r(Cg0^)g(Hg0)g-7' • A ser ies of dicarboxylic scida
were studied by Eocek and Tares who calculated the
retardation factor of emrboxyl group* ?he oj&daiion r a t e
conptant per ©ethylene group baa been determined to be ~»3 —1 «»1
5*2 x 10 dole eec which agrees well with the value
5*73 x 10 1-Qole oec eetabliohed in the aeriea of
n-parafflnc. A detailed otudy of the oxidation of forrsic acid
28
in sulphuric ©old cedluo ha© been carried out by eover&l ^4—Oft
inveetigatore* 9 # the reaction i© found to be approxi
mately f i r s t order with respect to formic acid end Cr(VI).
But i t depends upon the oquare of the ecid concentration
e t low ccidi ty , end follons h0# the Sanraett acidi ty
function a t M ^ o r cmcentrat tono. Patera9 8 d a t a M M
the iootope effect ( kjj/li^ » 7,2) and Bolvent isotope
effect (&^g(/% o • 5*7) which indicated thixt the reaction
involves too protons in the rote deterctlnias ©tep# On
the b&ois of above resu l t s two mechanisms wiro proposed*
0 0 0 4 II ^ II II
(A) H • H - C - CO * HgCrOj —fr» HC - 0 - Cr - OH * Bg0 OB
0 0
B - C • 0 - Cr - 03 ^ H • C0« • Or*1
^ - ^ OH
0
go
Teetheiner pointed out thet the chromic fecid
oildation of hydroxy eoido man extremely cosiplear on
account of the wide difference* in reaction product©*
29
For example Ino t i c aeid cao oxidised not a t the hydroxy 1
out a t the carboxyl group* 0 0 .
I l l 8H 4 SSJCrOj 4 3CH3C30R OGOI > 3CH3CB0 • 3C0g • 2Cr
+8HzO
2he above react ion doeo not involve an oxidat ion of far
l a c t i c ac id t o pyruvic ac id ao an in termedia te pyruvic a£itt» under the oxporinental condi t ions i n ques t ion ,
iOi undergoes fur ther oxidat ion lauoh nor© rap id ly than
i t undergoes decarboxylation • Batoro and Shy an IJarain
a l eo s tudied the oxida t ion of l a c t i c * sial ic and nandel ic
ecids by ebroiaie aeid in p e r c h l o r i c acid nediuD# fhey
aug&eated t h a t the aeebanlos
0
HgC ^ X CrQ£l2 ^ B S C 0 * S 2 C r 0 3 * 33°*» 11 0
p r o p e r by c r a r t and F r a n c i s 1 0 4 for th« oxidat ion of
cyc l i c secondary a lcohols «a« a l so app l i cab le to tftio
r eac t i on .
Vron the abov© review of tnc l i t e r a t u r e ro^erd ins
the oxidat ion of organic compounds by chromic ac id , i t
may be concluded t h a t although l a r g e amount of trork baa
been done on the use of t h i a oxidant but only scent
references a re ava i l ab le on toe oxidat ion of sa tu ra ted
33
fat ty ac ids . She few references which are reported
ar© only of quel l tc t lve nature end no systematic t?orlr has
bfceti doae on t&G Kftaeties «»d EJoenanisa of oxidation of
©aturatcd fe t ty acids by cferojsic acid. Zhe crortc described
in tMe thes is has boon c&rried out tdtt* a irtcw to study
tiie IiinoUco under vorioas oxpcriaeaital conditio**** r>nd
to tferow l i^l i t on tfto Doc&awisa of oarifiotion of fatty
ecids .
C H A P T E R I I
O0ETICS OF OXIDA2IOU OF tTOl^Al. CHAIB PATTY ACIB3
31
I8?R0JUC2I0!J
Saturated fatty acido are quite rea ls tent to
chemical oxidation, They arc ojddi&ed only by thooe
oxidants fjfcich attacfe paraff ins . Dairin * reported
a ser ies of pioneering studies of oxidation of fatty
acids by a railfl oxidising a&ent, hytiropen peroxide,
l a t e r on, he repeated e^perlnents with a vien to
tt«U. t h . nature of ketonlc oxidation products 1 0 9 .
ne shored that there ems a close resemblance betreen
tho oxidative processes in organioas and the oxidation
reactions affected by hydrogen peroxide. I t was shoai
that each acid froa butyric to otearic yielded a methyl-
-ketone (lUCO.CH«)f bavin? one carbon aton leas than
the parent a d d . The f i r s t step preouned by hin pas
the formation of a ketonic acid srhich underr/ent cecarbosy-
la t lon according to the followinr sehe&ct
n cigCiig coou — ^ n co cng COCH — ^ n cocii3 • co2 .
Chutterbuck and Haoer carried out the oxidation
of anr.onium ealtn of higher fatty acids by hydrogen
peroxide and arrived at the sane conclusion that the
32
f i r e t stop in the oxidation of srturated fat ty acids
woo the production of a ocries of Iteto rather then the
hyaroxy ac ids .
i n Allen and Uitceoann found that cer tain buffered
oxidation oyateros were useful for the oxidation of
aaturatod fa t ty acids by hydrogen peroxide. 2hey uoed
three different ca ta ly t i c systems- (TTaJiPO* - ^g0© systen,
UH3 - H?Og system and ( ^ 4 ) 3 HPO4 - IlgOg eyaten), and
obtained carbon dioxide as the raajor product (50-80$)•
Acetic acid and acetone were aleo obtained in significant
y ie lds . The authors interpreted the ca ta ly t ic effect of
the buffera as the in tensi f icat ion of the feeble oxidi
sing power of hydrogen peroxide by these subatances. I t
wan aosuncd that they pronoted the reduction of hyr'rofen
peroxide by eupplyinc hydrogen from the organic acid
used. The f inal oxidation of the oubstrato to carbon
dioxide vma a secondary reaction dependinr on the addi
tion of water and was not due pr inar i ly to the peroxide
i tool f .
The acid cotalyEca formation of peracids frora
a l iphat ic acida and hydropen peroxide faao been studied
kinet ical ly by Ogata and Snwakl112. They oboerved that
the ra te of peradd forcatlon together with equilibrium
33
constants increased with incrr-asin^ concentrations of
sulphuric acid and was correlated with the acidity of
Ecdius.
Sone further vrork on the oxidation of carboxylic
acid© by hyirogon peroxide is reported in the literature. 113
Hatcher studied the oxidation of propionic norrsal
and isobutyric acldo and suggested that they reacted in
the molecular form, flivlnn peracido as interncdlateo.
After the formation of perweido, hydroxylption occurred
at the °<-carbon atom and feeto acids trere forced* 114 Beresin oade a kinet ic study of reactions of
hydrogen peroxide with carboxyllc acids . I t was ohovm
that the decomposition of hydrogen peroxide In presence
of propionic acid uas a f i r s t order reaction t^ith the
ra te constant equal to that of the decomposition of
a cue cm a hydrogen peroxide* They also observed that the
evolution of carbon dioxide ras a f i r s t order reaction.
?he anount of carbon dioxide forcied a t 110-150°C was
a l inear function of the decree of hydrogen peroxide
decomposition. The resul t s were interpreted by tm ion-
raOioal oechanion,
l i s Ooniura tctroxidc x i s a remsrlsoble catalyst for
the oxidation processes because of i t a s t ab i l i t y in ocid,
34
basic end neutral media* 8g°2 ~ °* °4 systsea oxidizes
acetic and propionic acids to carbon dioxide quantlta-
tivoly. Foster and Pyne found a relation between the
oxidising action and catalytic decomposition of concen
trated hydrogen peroxide by oaniuo tetroxide. 'Zheir
nethod cade possible the simultaneous deternlnrtion of
the extent of oxidation^ (indicated by the assount of
carbon dioxide formed) and the extent of decomposition
of peroxide (indicated by the evolution of oxygen).
p-oxidation of propionic acid by hydrogen peroxide has 117
been reported on the ba s i s of product study •
Other oxidants hove a l so been used fo r the
oxidat ion of f a t t y acid©. Uixaitrov and flatan118 s tudied
the oxidat ion of f a t t y conocarboxylic ac ids by potassium
permanganate i n various nedia» Prper chromato.'rranliic
ana lys i s of the producto indica ted t h a t /^-oxidation
occurred i n a l k a l i n e and acid nedia Khlle both o<-and
/^-oxidations took p lace simultaneously i n n e u t r a l
s o l u t i o n s . The occurrence of /^-oxida t ion of f a t t y
acldo by potas iun pcman/*annto i n bas ic raciiuxa was
a l so ehov;n by ^eunhoeffer and Hatha .
Deupre obtained pyruvic acid on oxid is ing
nronionic acid by seleniun d ioyide . Per iod ic acid*
35
was however, shown to be incapable of oxid iz ing propionic
acid even a t 100°C i n a sealed tube . The oxid is ing ac t i on
of quinquevalent vanadium on some oxygenated compound© of 12P acyl ic s e r i e s eras determined by Horet tc and Gaudefroy *.
At hifh concentrat ion of vanadiun in 9U su lphur ic ac id ,
a c e t i c , p rop ion ic , v a l e r i c * p a l n i t i c and s t e a r i c acids
were unattached a t temperatures upto 100°C, but i s o b u t y r i c
and o l e i c ac ids reacted s lowly.
r a t e r s presented the evidence to prove tha t
the oxidat ion of carboxylie ac ids by Co(XII) took p lace
by inner sphere mechonion. I t involved the rapid rever -
oiblo formation of a coba l t i c complex broeteintf doran oloivly
with l i b e r a t i o n of f ree a lky l radical© which underwent
fur ther r e a c t i o n . The following mechanise was proposed
for the r eac t i on .
1. R.COgH • C0(n 2 0) |* ^ ^ ZT'R.GOgCo(H20>5^e* • H% H20.
2 . /"R.COgCoCHgOj^* S ^ n'+ C02 • Co8* • 5HgO
3 . H* • Co3* > R* • Co2*
4 . R* • HgO > • vm • n*
Chronic acid oxidat ion of carboxylic ac ids hao
been repor ted by severa l au thor s , but none of then has
36
carried! out the systematic kinet ic investigation of
thcoe react ions . Michael Polonovski reported that a
strong sulfochronic tsisturc rapidly oxidised the lower
fatty acids , but with weak cixturc no reaction t7as
found to take place. Sheso1 0 5*1 0 6 acida are oxidised
to acetic acid which renoins unattached tinder the experi
mental conditions. P e t i t 5 1 studied the oxi d isabi l i ty
of a number of organic compounds res i s t an t to oxidation.
In the oyidation of al iphntic acids he showed that oxidi-
Eability increase" v&th increasing chain length.
37
r a t e r l a l a .
Sulnnurlc acids Sulphuric acid A.I?. (B.B.IU) was
diluted with double d i s t i l l ed watery standardised with
III sodluia hydroxide*
Chronic acids Stocit solutions of chronic eoid rere
prepared by dissolving vrelfrhed aniount of AnnlaH (B.B.H)
potassiun dichronate in defini te voluncs of double
d i s t i l l ed water. Chromium tr ioxide solutions decoiaijoood
slowly becauoe of the s l ight aeount of the acid present
and hence trcre abandoned in favour of dichronate.
Acetic acids £cotie acid O*. T!erck) was uacd. The
solutions were prepared by dissolving neesure^ VOIUBEB
of the acid in conductivity water.
Sofiiuc thlosulphates ?hiosulphate solutions s?cre cade
up by dissolving the requis i te amounts of the solid
reagent followed by standardisation with potass!vm
fiic^romnto. rfhe solution t?no always freshly prepared
ami i t s concentration checked before use.
38
Sodium perchlorate* Sodium hydrogen sulphate end a l l
other reagents used were e i ther of B*B*H. AialaB or B*£*ercfc*
(J*B* ouallty* The solutions were made up fey dissolvine
weighed amounts of the reagents In double d i s t i l l e d water*
Organic acidss Propionic and butyric (£• Herefe) valer ie
(Mcht)t isotmtyric and isov&lerie^Cliedel) were ased as
supplied* Phenylaeetlc acid (Bush) was useS af ter reerya-
t a l l i c a t i o n .
Pm«qg.cneiitP.
SKperlnents wore conducted in oil thermostat held
to s&thia 0*1°C of the indicated tenperstnro* Solution©
of the desired concentrations for any particular experi
ment were n&de up fren stock solutions. She following
sequence was adopted for combining the reactantsi water
(to nake up the voluoe 125 d ) f sulphuric acid, substrate
and chromic acid* "?he reaction vessel containing water*
sulphuric acid and substrate and a flask containing dichro
ma te solution of required concentration were iooereed in the
thermostat for 15*20 ciinutca to attain the steady temperature,
fhe oxidation was commenced by adding the dlehroeate solution
to the reaction vessel* The time of half addition of the
oxidant solution was taken as the sero ties of the reaction*
the reaction vessel was vigorously shaken to ensure the
thorough nixinsr of the reactants*
2$
The progress of the reaction was followed iodo-
raetvteally. 10 nl aliguota of the reaction mixture were
vsithdrawn at suitable intervals of ti ne usually 10 minutes.
Thio aliquot v/as then discharged into 100 ml conical flask
containing 10 nl of boiled and cooled double distilled
waterf 10 ml of 5f> potassium lodido and a catalyst for
dichroaat©-iodide reaction.
fhe flask «ma covered with paper and kept in the
dark for 10 minutes. It was diluted with 20 ml of water
and titrated with standard sodium thlosulphato solution an
uoinp freshly prepared starch aa^indicator. She thio-
sulphate solution was restandardieed frequently during
the analysis due to the instability of the dilute solu~
tions (O.OIH). Every run was followed till at least
50;3 of the reaction rcaa coirplete.
* B.D. Sully hao reported that copper is a vnry powerful catalyst for the maction between potassium dichrocate and aotcssiun iodide. He showed that 1 ml of r/1000 cooper sulphate liberated 90" of iodide in 4 ninutes and 10 nl of the same solution afforded 90^ of the iodine in 45 seconds without a catalyst this de/ ree of reaction requires 30 ninutes.
do
The error introduced by air oxidation of iodide
ion under those experimental conditions was negligible*
?hc concentration of dichromat© solution did not chpn^e
appreciably in 5D sulphuric acid at the reaction teopera-
ture. Hence,no corrections due to these factors were
applied, Several identical seta were run simultaneously
in different vessels to check the reproducibility of
the results. It was observed that readings were accurate
to 0»5,J»
Uatere has reported the uptake of atmospheric
oxygen during ehrooie acid oxidations of organic compounds.
In order to study the effect of atoosoheric oxygen, three
identical reaction mixtures were tpken and oxygen, carbon
dioxide and nitrogen gaoos were bubbled throu. h thea.
Hate constants were found to approximate to the sane value
in all these cases. The oxidation, therefore, s?as studied
* in open vessels.
The concentrations of unreacted Cr(Vl) in coles
per litre wore calculated from the volume of thiosulphnte
used for each titration and have boen reported in the
tables. Deterninfttion of the specific rate constant (Jc)
was accomplished by plotting lo£ [Cr J vs. tine which
in each case yielded very food straight lines, whose
elooos nensuref? the first order rate constants.
4 1
Identification of oxidation products.
Acetic acid and carbon dioxide were the sain
products of oxidation of the fatty acids studied, 2hey
were confirned in the following raanner.
The organic acldo, sulphuric acid and an excess
of potaooium dichronat© were talren in the reaction vessel.
After the completion of oxidation (PA hrs.), the
reaction mixture nas transferred to a 200 ml distillation
flask with a side arn for the introduction of steam, fhe
flaslr was heated on a oantle. ?he temperature of the
distillation flasfc and the rate of steao input were
regulated so that a reasonable rate of distillation nas
obtained with a constant liquid lovel in the distillation
flask. She efficiency of the method was denonstrated by
distillation of a sanple of acetic acid from an aqueous
sulphuric acid - chronic acid mixture v&thout entrairuaent
of sulphuric acid. All distillates were tested with
bariun chloride to establish the absence of sulphuric
acid.
The identification of acetic acid was accomplished
by the lanthanun iodine test .
42
A drop of the teat solution was mixed on a spot
plate oith a drop of 5$ oolution of lanthemra nitrate
and a drop of COIN iodine solution. A drop of amonia
(IK) was added and in few nirmtea (in the prooenoe of
acetate) a blue ring developed around the drop of erxonia.
Benzoic add f7as obtained in the oxidation of 127 phonylecetic acid. It was detected by it© usual test •
The lime water test gave pooitivo indication of
carbon dioxide formation*
STUDIES OtfH PHOPIGHIC ACXB
43
Sho ra te of oiddatlon of propionic acM by
carooie ©ci4 was detemiaGd tty following tao progress
of tne reaction io&ometrta&lly. I t TOO foxsid that
f l ro t order equation r&fca rospoct to chronic aci4 fit®
troll in the data* & olicjrt inereaso in the ratio eons-*
tent noe oooorve<S tsacn ciironlo a c i i concentration was
dcereaocfi. Observation© showing the inflaenoo of
chromic aci«S concentration <m the ro te constent are
rocor&cd in tho follotTing taoleo*
FIG. 1
DEPENDENCE OF RATE CONSTANT ON CHROMIC ACID CONCENTRATION
1.0 I 0 30 60 90 120 150 180 210 240
TIME ( m m ) — -
44
? o b 1 c - X*
Dependence of ra to con ot ant on chronic a d d concentration.
yecp.7S±.l°C; ^ l l g S O ^ . 5.0n* £>ropionio co ld . / - 2*0£1.
/Sbraoie 7 166*55 x lO^n 83.32 x 10~% sold
fin©(oim0.> l O ^ p r ^ C t l ) 4*Ug$T^/ l O ^ J f r ^ H ) G ^ o ^ r 1 ^ W * M M M M i
0
so 60
90
120
150
180
S10
240
106*65
163*92
%m»m 150.25
143*20
138*63
132*62
127*53
122*43
2*821
2*214
2*196
2*176
2*105
2 . 1 4 1
2*122
2*109
2 .087
83*32
79*43
76*35
74*12
60*50
63*23
65*94
65*05
62 .76
1*920
i*899
1.877
1*869
1,841
1*833
1*819
1*812
1.797
*tete constant 1.38 x 10T3 1.30 x 10~3
(ads**1)
r i g . 1* Curve 1* Carve 2*
45
T a b l e - XI* Ttepandence of rmte ssmetssif ©S cferesic aeltf Qmemtwatlan,
?eS3$*7s£*i°Cf ^llgSO^J1* 6*0H, ^Propionic a c i d ^ e 2#0G*
^fbtooBlo./ 55*55 a 10~% 41.86 x lO*4!!
fSDeCnina.) 1 0 4 ^ i ^ < n ) 4*Xoc^5i?^7 l O ^ r ^ n ) 4 ^ © ^ * ^
0
30
6§
90
120
IS©
180
210
240
55* SS
52,01
49.32
46*87
43*23
43.00
40.75
30*74
30*40
1*744
1*716
1*693
1«670
1*655
1*633
1*610
1*899
1*334
41.66
36,07
34*31
33*54
30*70
30*20
28*57
26*80
83.00
1* 619
1*557
1*641
1*625
1*487
1*430
1.455
1.423
1*361
Eat© constant 1.50 x 10~s 1*52 x 10~3
Coin.-1)
Hg* 1* Curve 3* Curve 4*
a
? O b l 8 - lllm
BepenSene© of rate eousieat on e&roaic acia ©onceatretioa*
2eag*75£*l°Cf ^ g S O ^ J ^ S*ortf £>Fopionie aeldj^t 2.0H.
acid
Tlr;e(tnino.)
0
30
eo to
12©
ISO
180
210
240
33*33 x l O ^ D
l O ^ r ^ C H ) 4 # l o e # r
33*33
27*00
27*22
25*87
25,08
23.30
22*76
22+810
20*40
Eat© conotont 1*47 (lain.*"1)
1.SS2
1*445
1*435
1*412
1*390
1*SG9
1*387
X*9\B6
1*309
x 1 0 " 3
nj-
27*77 x 10*^0
1 0 4 ^ J f ^ { 0 ) 4 * l 0 ^ i f ^
27*77
21*75
19*95
19.43
18*86
17*96
17*17
16.32
15*48
1*86
1*443
1*337
1.301
1*288
1.27S
1*2S4
1*234
1*212
1.189
X ! 0 ~ 3
Fif> 1* Curve ©* Carve 6.
4?
fh© order of tenet I on with jfoofjoot to propionic
acid vm& aotominea by ves^in^ tfeo jnropioaio acid eon-
cerstrstion, keeping ©hroolc acts audi salwIrotftQ: &ei&
conooatratiaas constant* 'Jho *?at© eoitotit&to time
obtained a t different propionic acifl ootteoatmtio&s
troro plotted against oropioaic aei<a cone cat ra t Ion, A
s t r d g t i t lime paoeisc tlsroti^i tts© origin tmo obtained
c&i«& indicated tiiat the order of ttio rcection wita
roopoct to oubotreto i s «fiity» 2ho plot of r a t e constant
SB concentration io saotaa in fic» 3*
FIG. 2
DEPENDENCE OP RATE CONSTANT ON PROPIONIC ACID CONCENTRATION
o
o +
30 60 90 120 150 180 210 240
TIME (min) — *
48
2 a b 1 e - IV.
Dependence of ret© conetent on tfeo concentration of propioaio
£> r»u lon io J r 0*gO 0*8H sold
mcoCsiao.) l O ^ p ^ a ) 4*1©^SS*1^ 10 4^fy^7(r) 4 * l o ^ r ^ 7 MHMlMlMlHMllMII
0
30
CO
90
120
ISO
180
S10
240
33*33
3S.36
32 ,00
31 ,9a
31 .40
31 .04
30*62
30 .^3
89 .78
1*528
1*816
1.610
1*003
1*497
1*49!!
1*488
1*400
1*474
33* 3S
31*98
31*16
2 9 . 7 8
28*84
S 3 . 24
26 .92
26*18
2 5 . 1 1
1*522
1*503
1*404
1*474
1*460
1*46$
1.430
1.418
1*400
Rate c o n s t a n t ( t a i n . * 1 )
0 .47 x 1 (T 5 1*1S x 1 0 * 3
Fl£. e* Carve 1* Curve 8.
43
ty a b l e •» V*
Dependence of rat© eonstimt oa fc&o eoaoe»ti'ati«Hi of propionic aoi«.
tes|>.?s£.*0Ct O g S O ^ m S.OHi # r ^ « 33.33 x lO*4!!*
mm ii ii mi i n mi n i i . m m p — i — — » • — — « « » » • « « — i i nun i i mi mi n umiiiimi um ) IIIIHIII
iytopitmi&J^ l.on %.m
21o<*(t3in0.) lO^t^im 4*Xo^Jfr^7 lO^r^Cn} 4*lo0^r^
0
so m 80
120
ISO
ISO
2io
240
33.33
30,06
27.80
26.42
24.16
83.23
21.S8
£0*32
18.83
1*322
1.478
1*444
1*422
1.383
1*367
1*333
1*308
1*273
33*33
20*86
26.70
24*58
22.58
21*17
19*60
17.31
16.55
1*522
1*475
1*426
1.390
1*333
1*325
1*292
1*243
1*221
Bet© constant 2.38) x 10~3 3*22 x 1Q~3
Hf. 2* Curve 3. C«rv© 4*
FIRST ORDER DEPENDENCE OF RATE CONSTANT ON PROPIONIC ACID CONCENTRATION
FIG. 3
60
50
40
30
20
10
0.0 0-5 10 1.5 20 2-5 3<0 [PROPIONIC ACID]—-
58
T a b l e ~ ?I»
Dependence of r a t e constent on the ooae ©titration of Proploaie oc&eu
?eDp .?^ . l 0 Cf £yi2B04fJm S.OCf &v*l?m 53.33 x to*4!!
/ p r o p i o n i c . / 2 .00 2.SG ncid
fleoCcitts.) t O ^ r ^ C B ) 4 * 3 , 0 ^ * ^ lO^STr^n) 4*lo?aS^7
33*33 1.522
28.83 1.465
£4.30 1.39?
18.78 1.273
17.22 1.336
16*63 1.221
14.54 1.16?.
12.96 1.112
11.68 1.067
5.3? X 10~3
0
30
60
90
120
160
180
210
240
Ret© conatant ( is iu.*1)
33.33
29.82
25.41
22*30
10.67
17.77
15.83
14*34
13.14
4.3?
1*522
1.474
1.403
1.331
1.293
1.280
1.201
1.136
1.118
X 10~3
fig. 2. Curve 5 . Curve 6*
51
Hydrogen ion concentration variation
3?he influence of hydrogen ion on the rate constant
Has determined at constant chromic and propionic acid
concentration. Sulphuric acid concentration was varied carvtXAtdr
maintaining the ionic strengtfc^by usin# eodiun hydrogen
sulphate. Xt v/as observed that the quotients obtained by
dividing psendo f i r s t order ra te constants by corresponding
hydrogen ion concentration vary fron run to run. However,
when the f i r s t order r a t e constants were divided by square
of hydrogen ion concentration, the values BO obtained were
reasonably constant, showing second order dependence on
ac id i ty . The data are presented in the follotzing t ab les .
FIG. 4
EFFECT OF ACIDITY ON RATE CONSTANT
o
en o +
0.8 I
60 90 120 150 180 210 240 270 300
TIME ( m m ) *•
52
£ fi h 1 6 - TO*
Acidity iepcridor.co of the osiSatlsa r&ts©*
?«Esp.78*.l0C| £^ g S0 4 JT • ^ l laSS©^*. 6.0Ht
£^ropioal© aeiaJP* 2*0Ef ffr^m 33.33 x lO - 4 ^ .
£ \ S ° 4 - 7 3.SE5 4 » o n
2i»e<iai»s.) l O ^ r ^ C K ) 4 * 1 0 1 ^ ^ l O ^ r ^ H ) 4 * l o a # r ^
0
30
€0
90
120
160
160
210
240
270
State constant
33*53
29*43
27*24
28 .35
25*66
25.16
23.40
21 .90
21*40
20*80
1*06 X
1*022
1*468
1*430
1*420
1*409
1*401
1*369
1*340
1*330
1*318
10~ 3
33# 33
29*31
27*60
26 .28
24*90
25*78
23 .03
21*38
20*11
10*86
1*08 X
1*322
1*481
1*441
1*419
1.397
1.376
1*362
1*334
1*303
1*273
10~ S
(©An****)
» £ • 4 . Ctsrve 1» Carve 2 .
53
nue - mi* Acidity dependence of tfee oxiciotion ra te .
?esp*73*.l0C$ ^gSO^JV g^cmOoJ m S*03f
^>ropioalo ecldJT. g.0E} ^r^/m 33*33 x 10"4!!*
. O & g 8 0 ^ 4.50 8.0!J
seiGodslas.) 104^r^7Ce) 4*loG^fr^ l O ^ r ^ C K ) <k+Xtn$Z*^J
0
30
©5
90
ISO
100
160
S10
240
270
300
Rate
33* 3M
£9*14
26*70
24.02
23.56
22*24
20*85
19*10
17*84
16*60
• »
constant 2.56 x
1*622
1*434
1*428
1.394
1*372
1.347
1.31S
1*281
1.251
1*820
•
10~S
33*33
28.25
23*18
22*90
20.44
18*70
17.23
16*22
1S.63
13*23
«
3*35
1.522
1*431
1*401
1*360
1*310
1.S71
1*230
1.210
1*194
1.102
-
x 10" 3
(mill* )
Etf> 4* Curv© 3* Cnrvo 4*
54
T a b l e - IX.
Acidity fi©pea4ea*© ©f tti© oxidation rate.
£>ropioatG acia./wa.OHt ^ r ^ * 33*33 at 10"%. u in M i l l — « • — m IIIIIIII i i i n mi i ii ui Hum in—;mm—iw«Mninn,iimiiimim—urn n m . • n u m m m I P H W I I I immmmmmmmmmmm
£"&2S04-7 S.8S
1!ine(E&*i0.) 104^Tr^7Cfi) ^ l o ^ r ^ f /
0
30
€0
00
120
160
180
210
240
270
300
33.33
27.18
22*90
20.50
18.14
16.42
14.70
11.45
0.17
3.C8
mm
1.822
1.434
1*330
1.310
1.258
1.215
1.167
1.060
0.962
0.918
m
?,ote oonotunt 4.61 x iO"*3
Fie. 4 . Curve 5.
f a b l e -» X.
Acidity dependence of the oxidation r a t e .
ffroplmte atAAjm 2#0IS| £&v*^J** S3
SiaeColiMi.) JO^gSf^CK) 4*lo(a3Tr^7
0
so 40
SO
80
too iao 140
160
180
33.33
23.00
24.20
20.03
18.67
17.00
16.13
14.00
12.06
11.20
1.522
1.447
1*383
1,320
1.867
1.230
1.207
1.154
1.081
1.049
Rat© constant 5.37 x 10*3
{ola. )
f ir* 4 . Curve 6.
5t>
$ff«ot of acidity on tha rat« constant.
M » * M W M M « M > M W
9*8 12.28 1.66 4*74 1*38
4,0 1«»00 1,96 4,95 1,24
4*8 co.ee 2.6« 8.«o nee
6.0 25.00 8.88 7,80 1*48
8*8 30.25 4.61 8,88 1.82
6.0 36.0 8*87 8*89 1.49
• •MMMIWHlMMIMIMWlWIMNW^
5?
gpfraeratutgo dependency
fho variation of reaction ra te with ienpcrattiro
V&Q u t i l i s ed to obtnin to© tgnergy of ectivaiion end other
themodynisisic peraaetoro. ffee reaction tm€er consideration
«o»« thoroforOjOtutfiod e t five different tcisnorafcureo a t
eonotnnt cone exit r a t i one of ihs reactento, £h© plot of
log E V8 • i - gave a s t ra ight l i ne fros the olofio of ssnicli
the energy of act ivat ion xmo calculated sa«S fouM to bo
1?#0 Ileal* She h«at of act ivation ( A H ) e»a entropy
of activation { A S^) Woyo calculated by mc&ine UBO of
tho follotjing oquetiono.
&« «g& e (pyrine Equation)
AC » — ""wmiw $Mmmi+mmmm
2 "Caere tho oyobol© nave thoir usual noaalns* She values ar©
&W*» 16.3 KcaX
AO + »«-so*8i en*
FIG. 5 TEMPERATURE DEPENDENCE OF THE RATE CONSTANT
1.0 I • • i I I I 1 1 1 1 I L
0 10 20 30 40 50 60 70 80 90 100 110 120
TIME (m in ) >
58
x B % X e - H I «s
teapeffBtwe fiepoaienee of tfe© reaction r a t e ,
£\»SG44,7* B.OEf £>ropi.(mio acid^/w 2.2H* {gx^Jm 33.33 at 10"%.
feisparatttre 343°K
fido(i3sin8.) X 0 4 ^ r ^ U ) S + X o g ^ ^ f f M^Sf r 'S r tH) 4 * X o ^ r 1 ^ 7 MfffMMMVMMMN
0
£0
40
60
80
too 120
100
180
210
3 3 . 3 3
30.20
28.37
26 .66
£4*94
£3 .72
22 .60
20 .04
18 .75
if. so
X»$22
1*480
1.4S3
1.426
1.397
X.37S
1.352
1.302
t ara 1.238
33 .33
30 .06
28.80
83 .70
2 1 . 6E
19.08
17 .70
16.60
16 .03
15.30
1.5S2
1.478
1*428
1*378
1.335
1.880
1.248
1.280
1.188
1.148
Bate constant 3.10 ar 10~3 4.62 x 10*3
(o i» . )
Sic* 5 . Curve 1. Curve 2 .
5J
f a l l e - XXII*
2eoperatare dependence of the reaction rete*
^ S O ^ - 6.08, p r o p i o n i c aciflJT. 8 . S n , ffr^J. 83.33 , « r S .
fcoperaturfc 3S3°K 358%
fioeCein©,) lO^ r ' JZCn) <M©gP**27 i O 4 ^ * ^ ! ^ MQ^^J *U**SNM«»MMNM«Wff«^^
0
10
20
30
40
60
60
80
100
120
33.33 29.78
£7*98
25,82
23.87
21.92
20.55
18.32
16.82
14*96
1*522 1.474
1.446
1.412
1*378
1.341
1.313
1.263
1.218
1.175
33.33 89.37
20.92
24.10
22.18
20.80
19*10
16.32
14*30
12.02
1.522 1*463
1*430
1,382
1*346
1*318
1.231
1.226
1.168
1.108
Sate constant 6*70 x !0~3 9.23 x 10~S
(adn.*1)
Fig* 5. Curve 3* Carve 4.
FIG. 6 ACTIVATION ENERGY
1.4
1.2
en o 1.0 +
in
0.8
06 1-e ©-« e — ' — 27.5 2 8 0 2 8 5
1 * 1 0 * T
29.0 29.5
&3
S a b l e - XIV*
i'espersturc <Sap©»4©ns© of the reaction r a t e .
Tenporaturo 363 It
HSetnliuu) l O ^ i r ^ C n } 4 * l o c # r * 5 r
0
10
20
30
40
SO
€0
70
80
90
100
33*33
20.84
£5.40
22.70
20.74
19.10
17,37
14*90
13.18
12,13
10.86
1.822
1,460
1.403
1.336
1.317
1.281
1.240
1.173
1*120
1*084
1.036
Bate const ant 11.98 x 10*** (rain.*1)
Hg* 8. Carve 8.
si
Influence of Ionic otren^th
Sao ©ffect of ionic strength on the ra te
constant tsu© ©aroDlnod by adding varying oraounto of
oodlun perchlorotc* fhe otfaor footers ouch GS the
concentrations of the reactents ond toEoeratnro t?©re 1/
kept ideniloisl* A plot of /* ' S V©. log & doe© not
giv© any ei^ttifiecnt inforeiBtion bee mice the lonlo
otrengtho ar© not i n tho rrjoco in which Bebyo->Huolxcl
theory i s applicable* the r e su l t s ©h©t?i»s *&© imflneneo
of ionic etrensth on tho ra te const on t ore teblod below.
FIG. 7 DEPENDENCE OF RATE CONSTANT ON IONIC STRENGTH
> O
cn o
170 h
160 F
'1-50 Y
1-40 Y
1.30 30 60 90 120 150 180 210 240
TIME (min) •
S2
ft a b l e • XV«
nffeet of ionic o*r<mgtft on tho roto conotant.
£ocp.80£.i°Cf ^ligSO^J^w 4.5£Jf p r o p i o n i c eeidJTw 2.0T!f
/^T^JM 33.33 x lO*4!!.
m.~- 'iiwf—i
C ionic 4.50 5.0 stroartii ?lco(clna.) 104^r^7(E) 4 * l o ^ r ^ iO^JTr^n) 4+lo<^8i^7
0
so 60
90
120
150
ISO
210
240
41.66
83.55
s?.oa 3D.86
34.80
33.66
32.86
32.03
31.62
1.619
1*336
1*569
1.654
1.541
1.527
1.516
1.505
1.500
41.66
58.30
37.35
37.10
35.88
34.85
34.46
32.68
31.31
1*619
1.583
1.572
1.569
1.554
1*542
1.524
1.514
1.495
Sate constant 0.96 % 1Q~3 1.00 x 10*s
(rnin., )
Tie* '• Carve 1. Carv® 2.
63
2 a b l e - XVJU
Effect of l e a i e atveagtli os the rat© conetent.
?cr^#80i«l°C$ £^2QQ4^m , S^* p r o p i o n i c aoidj^e 2.0!3f
$**l7* 41,66 x lO^H. |l«MMtMltia#M«HMMHIMMPaMM^
Cbt&iQtJ uon um , j
loal© S.SI3 S.OtS
?iiae(fii«e.5 1 0 4 ^ B r ^ n ) 4*loa^r^J l O ^ r ^ n ) 4 * l o ^ r ^ NMMMWMMttM
0
30
SO
90
120
ISO
1G0
210
240
41*66
20.24
38.38
37.18
36.67
35.79
34.76
32.51
30.81
1.619
1*303
1.084
1.570
1.863
1.583
1.541
1.812
1.430
41.66
39.03
37.37
36.00
34.25
33 . S3
32.36
31.04
20.30
1.619
1.601
1.572
1.557
1.534
1.529
1.510
1.491
1.467
Hate constant 1.10 x 10~s 1.42 x 1Q~3 •1 (dn. )
Fii»» 7. Curve 3. Curve 4.
64
j o u e - jnni
Kffcot of ionic Btvm;rth on the r a t e constant*
$eos>.ao*.l°C| ^ g S O ^ - *"»StS| p r o p i o n i c acidJ^S.ODj
4&^ - « . « . «r«n.
Z ^ e O l O ^ 2.012
Ionia 6.BB *MII« l l«»»«IWMW^WIWMia«M^^ , • • ! • • • inn—HHWW
1Slm{tdn@») ixfiffr^i/iU) 4 * l o ^ f ^ 7
0
SO
60
90
ISO
160
180
210
240
Hat© conotant
41 .66
39*08
37*41
35.07
31 .98
31 .11
28 .24
2 6 . 7 3
25 .46
1.83 X
1.619
1.592
1.073
1.54&
1.505
1.493
1 .451
1.427
1.406
10~S
(raia. )
Flf;. 7 . Curve $•
.,flqr«p*i, of M9*H,M&$,
Hate coaotsato srtltU reference to chronic ©oi«t
wore determined for tfc© reaction in absence tm& ttt
tfee presence of imtloii© onouaite of ace t ic aeitU I t
w&a foa»d tbs t the r&to constant© increased with tfee
increaain/r cooauts of acet ic ccid. S&© data are
presented below*
FIG. 8
EFFECT OF ACETIC ACID ON RATE CONSTANT
0 20 40 60 80 100 120 140 160 180 200
TIME (min) *
66
? o U c * XtflXI*
Influence of soetlc eoid or. the- r s t e of oridat icn.
5?0Dp.8O**l°Cf ^TfgSO^a S.OH* ^Prop ion ic s c i ^ J ^ 2*0K|
£*jioett0 7 NIL o.azs
acid
HooCtdfts.) lO^S&r'Jtn) 4 ^ 1 0 ^ * ^ 10 4 ^ r^7 ( l l ) 4•lo^5?rVi7 ,
0
go
eo
80
100
120
140
160
leo mi I I I '~ • - 'I ' "n i r i i i i nil. I ni l III. Jin. ii I nun I n u l l u m I n mill in
list© constant f .98 x 10~3 11.50 x 10~s
l ip* 8. Curv© 1* Cunre 2*
26.66
83.92
20.1?
16*31
14.18
1 1 . IB
9.21
0,18
7.60
1.425
1*378
1.304
1.212
1.161
1.04?
0.964
0.912
0.S61
26.66
24.14
13*40
16.24
13.00
10.04
8.63
6*75
5.30
3.80
1*426
1.382
1*266
1.210
1*114
1.011
0*936
0*829
0*724
0*579
67
T a b i c - XIX*
Influence of acet ic eo l i oa tiio rate of oxidation.
?<sap.80l.loC| ^ l l g S O ^ t t 6.0!If £>ropionie acifij'"- 2*0£|
^ r * ^ * 26*66 x lO*4!!.
£"&cetlcj* 0.SK 1.0tl scid
Ttoedains.) l O ^ j r ^ C n } 4*l0g^r ? 5 '* 10 4 ^r^7( t l> 4 ^ 1 o ^ r ^ 7
0
20
40
60
80
too 120
140
160
180
TTate
26,66
23*70
19* SO
14.74
IS* 36
9*56
3*34
7*18
5*36
3 .16
c o n o t a n t 11*50
1.425
1*374
1.233
1*163
1.008
0*980
0 . 0 2 1
0 .856
0.729
0*500
X 10~ 3
26 .66
23*63
17 .87
1 3 . m
10 .13
7 . 6 9
S*80
6*00
3 .62
mm
14*04
1.428
1*373
1*244
1.122
1.005
0*886
0m?m
0.699
0.959
.
x 10*3
(ain* )
FlC* 8* Otirve S* Curve 4 .
68
$ a to 1 © - XX*
Inf luence of ©cotlc ac id on tk@ ret© of oxidation*
?ecp.80-*.l0C f £^2®0bJa 8 » o n * £yrop±<mtG eeld_7« 2.0H*
^AQ&tioJ" i.en 2*on
a d d
fitoedBtos.) 1 0 4 ^ r ^ 7 ( n ) 4 + l o ^ r * ? / l O ^ r ^ C K ) 4+1*^*1/
0 26*66 1.423
20 22.62 1,364
40 19*90 1,199
60 18*52 0.976
80 8*70 0.939
100 . 6,17 0*790
ISO 8*04 0.702
140 3*90 0.390
160 3.30 0*518
180 • ** *» <-*
Cat© constant 14.73 x 10~3 17.04 x 10**3
Cnin." 1)
Fir* 8» Curve 8 . Curve 6*
26.66
19*00
15*21
9*95
5.23
3*85
2.71
2.40
1.37
1*425
1.278
1.182
0.998
0.718
0.683
0*433
0.380
0*198
STUDIES mm mnnc ACID
6J
Ortior in C&roiaio aci<3
8*0 ra*e of aioappanraace of Cr(?X) xmo e f i r s t
order reaction in tfao preoeac© of-Duty trie eci<U Kooovor*
as the conoentratioa of Cr{"tfX) mo decreased, the nsgrti«
ttxdo of f i r s t order ra to constants increased, but not
t o an extent ouch that a Mfho* or<tor teres in £pr^Z
nay fee defined* TUc data representing the variat ion
in ret© eonataato with varying cofieeatretioao of (Tr ,/"
are ©ho-m i n the follooio^ tobies .
FIG.9 DEPENDENCE OF RATE CONSTANT ON CHROMIC ACID CONCENTRATION
2-0
1-8
1.6
o 1-2 +•
1
2
0 20 40 60 80 100 120 140 160 180 TIME ( m i n ) •-
78
U E b H - XX2.
Depend one G of rate constant ©a cUrooic aeia concentration.
S<asp.80±.l0C? ^gSO^jJT.1 S.OSIf ^ l i a t y r l e GCia,/** O.SE.
£~0JirocieJ r s$*33 a 10~% 88.85 X l<T*n ©©id
f ine* s ins . ) l O ^ r ^ O ) 4 4 o # f ^ 7 l O ^ J T r ^ E ) 4 * l o ^ J f r ^ J r
0
0 )
40
60
80
100
120
140
160
180
83*33
71 .04
©1.77
0 3 . OS
47 .18
42 .30
36 .40
3 1 . 7 1
26 ,26
££ .08
1.920
1.850
1.790
1.724
1.673
1.627
1.861
1.801
1.419
1.343
8 8 . 8 5
4 7 . 8 6
41 .09
36 .02
34 .26
30 .98
27 .33
EK. 17
17.38
1.744
1.630
1.6S0
1.556
1.834
1.491
1.436
1.348
1.S40
«•>
Hrto eonotant 0.90 x 10~* 6.90 x 10" (oin. )
fi^. 9. Curve 1. Curve 2.
?i
• . - a b l e - XTO* i>
impendence of ff&te con©tent on chronic acid coneeairaticm.
2 ts^#S0^»l°<5| ^"HgSQ^* S.Onf £ " W y 2 i c acld^/" O.SH.
l»W*»*MtM»|IMN|N*WMW^^
£*,CferocJt<2jr 41.66 x 10~*n 33.33 X l<r*n acid
?ioe(roiii0.) l O ^ ^ / C L ) 4+%QG@r**f Iffi/Br^tS) 4 * 1 0 ^ 1 ^ MrtHMMMNUMNMI
0
20
40
60
00
100
ISO
140
160
130
41*66
< W » * l l
S8.0S
25*2®
22 .38
20.4S
17 .86
I S . 2?
13.48
«*
1*619
1.533
1.461
1*404
1.349
1*310
USB2
1.184
1.1S3
*»
S3* S3
27 .S5
22 .7$
19 .32
16.98
14.86
1S.01
10.00
8 .373
«
1*822
1*436
1.3S7
1*286
1.230
1.154
1.079
1*000
0 . 9 8 8
«»
Bete constant 7.60 x 10~3 7*33 x 10~3
( B i n . )
II > 9 . Curve 3* Carve 4*
n
? © i» i © - m i x .
•tapondeatht of ra te constant on chronic eolii concentration.
^ C h r o n i c / 27.77 x 10"*% 23#80 X 10*%! oci<5
ficiedslne) l O ^ p V ^ t l ) 4 * l o ^ r ? f 7 i O ^ r ^ C O ) 4 * l o e # ^
0
20
40
€0
80
too ISO
140
160
180
27.77
20.79
16.60
13*18
11.89
9.81
8.87
7.49
$.67
«,
1*443
1.317
1*217
1.180
1*070
0.978
0.917
0.075
0.8S4
* •
23.80
18.80
13.60
10*97
0*04
8 . SO
0.70
0*61
4.38
•m.
1.376
i«28S
1*133
1*040
0*056
0.013
0.826
0*749
0.042
m-
Kcto constant 3.23 x 10*3 8.75 x 10~3
f ig . 0* Curve 5* Curve 6*
73
C a b l e - XXIf.
:Dep@R<I<?Bce of r a t e ccmctgfit on cfcronic acid cimcentraMwn.
SV ef3p.80Z.i°Cf ^ g S O ^ . S.GDi £%utyrto a c i d , / * 0.5H*
£mGhmmcmf 80.83 x 10*% 18.01 31 10*% add
MMNMHNNMMM
SlDoCoiao.) S O ^ r ^ C ) 4 4 1 0 ^ ? ^ tO^r^CL") ^ I O Q ^ J ? ^
0
10
m m 40
so 60
70
80
00
100
20.83
18.50
16,53
14.83
13.40
1S.05
11.08
10*84
9.86
8.92
8.33
1.318
1.267
1*218
1.171
1.127
1.080
1.041
1.010
0.971
0.950
0.920
1S.S1
14.10
12.06
10.9S
10.10
9.E7
8.48
7.87
7.45
7.06
6.32
1.867
1.149
1.081
1.089
1.004
0.967
0.928
0.898
0.87S
0*B4&
0.800
?ate constant 8.23 % 10~S 8.23 x 10~3
(oin*. )
Fig. 9. Curve 7.
n
Sh© order of tfao reaction with ron^oot to
butyric oci<3 vsm a©t«0rciBoa i a ttie ©ceo Iteohion ae
in t&c cauo of propionic ccitf. Ciaroalc acifi tm&
sulphuric ©csi<J coaoent ra t ions t»ore Irepfc ©on© toat
and butyric &ci# ©oneontrcitioii oe® varied etcqraloe*
!?he plot of ret© eofistcJSt Vo coaoentration gnv© Q
strain*** l ino iadioatifif f i r s t orfier dcpenaosice on
butyric oeltf. the typical p lo t io sliom i a figur© 11»
FIG.10
DEPENDENCE OF RATE CONSTANT ON BUTYRIC ACID CONCENTRATION
1.0 I ' • • I l I I I I L
0 30 60 90 120 150 180 210 240 270 300
TIME(min) *
75
2 a h 1 a - XX7.
Dependence of rate conntent cm the concentra t ion of btttsyric a c l £ .
1»e^»»80i.l*C| ^ l l g S O ^ a 5.0H* ^ ^ » 33.33 It !0~%3.
<<IWI»*I**«M*1II*»MMHH^^ i | i ^ « « l » M « W M » W » l » H » » > * » l ^
/TBu ty r lo j r 60.0 x 10"£I3 33.0 s 10*20 &Ql<£
21BC(E1«O.) lO^r^Cn) 4^Xo^trVi7 iO^r^ ta ) Moetpr^f mmmummm HHIMMHIJIW
0
20
GO
90
ISO
ISO
ISO
210
240
270
300
3 3 . S3
25.31
10.80
U . ? ?
0.14
7.78
0.3?
mm-
HWri
-
M»
1*522
1.403
U&28
1.071
0.060
0.890
0.730
»
•»
-
«*
33.33
27.40
S3. 86
21.11
18.28
10.10
14*33
12.30
10.80
9.74
•
1.SS2
1.43?
1*37?
1*324
1.262
1.S06
1.15C
1.091
1*033
0*988
«»
t 'eto constant 8.44 * 10"*3 4.60 x 10~S
»r . io. Curve t . Curv© 2 .
78
? a1> I e - XOT,
Dopendcnee of r a t e eonotrmt on tho concent nat ion of b u t y r i c a c id .
?ens>.802.1oCf ^ g S O ^ e 8.0!2| ff^J * 33.S3 * iff"4
£ " k » ^ r l c „ 7 28.0 a 10"% S20.0 x 10~2tl
^iiseC^n©.) I O ^ J T ^ S ) A^IQ^T^J to€£?r^2%ny 4 * i o ^ r ^ 7
0
so m m
120
150
180
S10
240
270
300
33.33
23.60
24.94
Bt.83
19.47
17.30
1&.41
13.71
15.03
10.63
*»
1.B2S
1.456
1.397
1.339
1.839
1.238
1.187
1.137
1.080
1 . 0 3
<•>
33.33
29.51
87.OS
24.74
21.94
20.89
19.42
17.72
16.76
-
<m
umn 1.471
1*432
1*393
1.341
1.320
1.230
1.248
1.284
•»
«.
Hate eonotaat 4.03 x 10~3 S.88 x 10~S
( s i t u * 1 )
F i* . 10. Curve 3 . Outrvo 4 .
77
T a b l e - X3VIX.
Bep€n<$«saee of ra te constant on the coaceot*ation of but j r io ecid*
SeGSuSO^l^Ci ^ I f g S O ^ * S.OHf ^ f C r ^ - i 33.33 x W~*Um
1 '" ""' ""•"" win w mi mil i.iiiiiniiiiiii.Miiiini iinii i i •imn.n m . urn m« m II i iiiinn •.niin.n , n m iniiimimi muiinwii»n«.i»i
^Butyric , / 15.3 x 10*% 10.0 x i0*%2 acid
S*ee{aiii3.) l O ^ r ^ E J ) 4 * l o ^ r ^ 7 I Q ^ p r ^ H ) 4 * l o & $ r ^
0
so 60
90
ISO
180
180
210
240
270
300
Hate
33*33
30,60
28.00
26.94
25.03
23.33
21.83
20.16
10,24
17*83
«•
1*622 33»33
1.463
1.447
1.430
1.398
1.372
1.330
1.304
1*284
1.251
•
const e a t 2.30 x 10~3
32.31
30.90
30.30
29.34
23.26
26.71
25.56
24.42
-
•mm
1.38
1.622
1.309
1.490
1.481
1.467
1*451
1*426
1.40?
1,387
*»
•
x 10" 3
(sain.*1)
Ham 10. Curve 8 . Curve 6.
FIRST ORDER DEPENDENCE OF RATE CONSTANT ON ACID CONCENTRATION
BUTYRIC
FIG. 11
x
90
80
70
60
50
40
30
20
10
0
-
Qy
—Q-LQ—e—e-1-
y/Q
©— —e—
' o
' 0 ' L
o/
i 0
10 15 20 25 30 35 40
10* [BUTYRIC ACID]—^
45 50
78
S u fe .1 e - txniU
Dependoneo of r a t e oonotant on the concentration o£ fcutyrie acid.
[email protected]^.i°ci ZThgSO^* s.oni {gv^Jr* 33.33 x 10*%.
^ f b u t y r i e j r 6.6 at ac id
10*%
<2ijae{iain0.) 104/JSr*l7tE) 4 + 1 0 ^ 1 ? ^
0 33.33
30 SI.10
60 20.82
00 29.44
180 28.30
180 27.92
180 26.82
210 26.32
240 85.55
270 24.8S
300
Rate conatant 0, (Din.* 1 )
1.522
1.492
1.474
1.469
1.451
1.445
1.428
1.400
1.407
1.395
-
.96 X 10~S
4.0 % Hf2*!
io4^JTr^7ta) 4*1O#JST^
*53. 3S
31*65
30.64
29.88
29.51
29.01
28.51
28.13
27.82
27.81
-
0.40
1.522
1.500
1.486
1.470
1.471
1.462
1*465
1.449
1.444
1.439
<m
X 1 0 ~ 3
Tift* 10. Cnrvo 7* Curr© 8.
79
Hydrogen Ion coneontrfition variat ion
For studying tae effect of teydrogca ion OR tho
r a t s , cspoiriG63sts *.?«re porforGsod td th different cjoncen-
txnttono of sulphuric &«i<3« Ionic otronr&n ana oulphot©
contest of the reaction otrtwro m s EasintatnoS cosotcnt
by adding requis i te enotmta of ©o&iuD ay<Iro;»en onlphato.
2fee concentration of iay jro ef* ion cao calpwlotoQ on the
aoDunption ttiat f i r s t diooooiation of sulphuric cold,
H o 3 0 A ™»>. »•» H* • SSO"
i© eotaplet© m6 the second <iiesoolation io aoflinibl©*
Observations a t Kmriou© toy&Kicen ion concentrations
are tooled oolo?/*
FrG-12
ACIDITY DEPENDENCE OF THE RATE CONSTANT
en o +
0 20 40 60 80 100 120 140 160 180 200
TIME (min) »
80
S a b l e * XXIX*
Acidity depeadoiaee of tko oxidation rote*
SeBp.702.1% C&2mfr? * ^ b a a a o ^ j ^ 6*0S|
£>tlt3rilc BeidJ^* 0.812s # » ^ 7 « 26*68 X l©"4!!.
Tisedstna.) i O ^ r ^ C K ) A+lae&tPj tO^ffr^in) 4*log^Prv]7
0
go
40
60
00
iOO
120
140
160
180
800
26.66
28* 32
24*18
22*67
£1 .70
21 .43
20*90
20 .34
19*88
18*90
18* 22
1.425
1.403
1.333
l .SSS
1.336
1*331
1.9S0
1*308
1*298
1*876
1.260
26*86
84*98
23*76
22*87
21*81
20*76
19 .13
18 .23
17 .60
16*18
15.23
1.425
1.397
1.376
1*359
1*338
1*317
1.281
1.260
1*245
1.209
1*184
Bat© constant 2.92 x 10" ' 3.70 x 10" (oin.*'1)
H.g« 12* Curve 1* Curv© 2*
SI
f a b l e - %&&•
Acidity aopondenoe of the osldation r a t e .
2©3p.7O*.l0Cf C^zm^ * £^mm&Jm e*0E* O t t ^ ^ « GCi<3jr*0.S£lt
< f \ 8 0 4 - 7 4.00 4.513 «MNIii^Mttl»MM4WMMMI«*1MWW^^
fiaeCoiits.) m^v^JiU) tk+Xoggtv^ l O ^ r ^ C n ) 4 * l o ^ * ^ 7
0
m 40
60
80
100
120
140
160
180
200
26 . GO
22 .S1
80*24
18* 30
17.22
15*11
14.35
13*80
13*06
11*82
,»
1.425
1*352
1*306
1*202
1*236
1.179
1.1S7
1*130
1*116
1*072
«*
26 .66
21*42
19.24
17*01
14*62
13*64
11 .63
10*00
8* W
7 . 2 8
a*
1.428
1.330
1.284
1.230
1*160
1*133
1*063
1*000
0 .911
0*862
«.
Pat© constant 4*90 a 10*3 6.83 at 10*3
(fain.""1}
Eig* 12. Curve 3* Curve 4*
82
S a b l e - XXXI*
Acidity (dependence of the oxidation rate*
fe&p*70£.l°Cf C®2m4r? * Z^eSS0 4 - /« 8.0H|
£"feiityne aetaJP* 0.8B| /Wr^m 26.66 x 1G~4I!.
£ \ 8 % / 8*011 5.SH
ftoeCciae.) lO^r^Cc) 4*Xo^/j7 iO^r^G) 4+lo#5&r^
0
go
40
60
30
100
120
140
160
180
200
Hate
26*66
10.94
17*00
14*86
12.3S
11.80
7.92
6*83
6*02
5*20
-
1*428
1*800
1*230
1*163
1*091
1*060
0*898
0*837
0*770
0*716
•*
conatant 8*64 at 10~3
26*66
18*80
17*37
14*81
0*12
6*37
8 .11
3.30
2*74
1.90
•
11.06
1.425
1.S74
1*240
1*170
0*960
0.804
0.708
0.818
0*439
0*284
mm
x 10~3
( e l i u * 1 ) IIM mmmmmmmmm»
fig* 12* Curve 8* Cmrv© 6*
83
T a b l e - XXXII.
Effect of acidi ty on tin© rote constant
(n) (am.-1) £Tjr ZX.72
(l.woffKn^) Cl8«BOlo"2oin.""1)
3.0 9 .00 2.92 0.97 3.26
3.5 12.25 3.70 1.05 3.02
4.0 16.00 4.90 1.22 3.06
4 .5 20.25 6.83 1.51 3.37
5.0 25.00 8*64 1.72 3.44
5 .5 30.25 11.06 2 .01 3.65
84
Under ident ica l conditions of reactonto eoncea-
trct iono ana a t constant ionio etro»gt»» the reaction
ban fcom studied a t *i*o difforont teno«siratureo« 2hm
reaction could not bo studied ©t lower tcnperature
becatioo too ra te i© too olocr to bo teinetic&liy studied*
HoCTOver, tno act ivat ion oaer^y and other tnerco^srnaae
functions of tae process i?oro calculator froo throe
eojuattone %lvm oarl ior* fno oners*? of eetixy&tioa w&s
found to bo 18#4 Seal mA til© volnes of A S^and
A B* aro ttmf Koal ©a<S *26. i en respectively*
FIG-13 TEMPERATURE DEPENDENCE OF THE OXIDATION RATE
> *-o
o> o +
s j
1.2
1.0
0-6 10 20 30 40 50 60 70 80 90 100
TfME(min) -
85
T & u e - xxxxn« tmp&m&UTG <3©p€»£ess© &S t&© roaotlon ra te ,
3 ^ 7 * 33.33 X 10~%*
fao^eroettr© 343% 340%
fi^CsiiHi.) y^ffr^m M o g g f e ^ I G ^ r ^ H ) 4*lof5fl5rV37
0
10
m 30
40
m m 70
80
90
100
W9t * *
32*61
31.40
30*31
29.41
23*44
87,64
25,00
24*88
21*23
-
i.sss 1.S16
1*497
1,481
1*468
1.454
1*441
1.417
1*387
1*327
-
33.33
30.11
28.01
23.98
25.19
23.03
21.92
20*60
19*91
19*28
18.60
1*522
1#478
1*447
1*414
1*401
1*362
1.340
1*314
1.301
1.285
1*267
Hate constant (nin. )
3*60 x 10 - 3
6,08 x 10 k-»3
HIT* 13. Carre 1. Cursr© 2*
88
7 a U e - XXOT* T^rvocrF.turc dcpcndonco of the reaction r a t e ,
^ a g s 0 4 - 7 * 6 * 0 t f | £"k»*y**° e e i d j ^ O.BGf
3 ^ J * 33*33 x l o ^ n .
Senporafcur© 353% 3S8°K: *ww«iM»»»>»M»«*»«i»wiM<MiMriM»r<»Mw^^ w*mmmmmmtmmmimmmmmmmiimmmmmmiimmm*mm»rmimn* u n l i t — — — i • »
S?la©(aiaa.) l O ^ r ^ n ) 4*loc#p?i7 10 4 ^ r^ [ r i ) &4&og$r^Z
0
10
so so m 50
m 70
80
90
100
33*33
30 .06
27*24
24,00
22* $2
20*51
18.67
17*40
16.28
15.20
13*97
1.522
1.475
1*435
1*394
1.354
1*312
1 .271
1*240
1*211
1*181
1*145
33*33
28 .01
23 .50
20 .64
17*20
14*20
12.94
11*22
9 . 1 6
8 . 2 3
7 . 5 0
1.522
1.447
1 .371
1*314
1*237
1*152
1.112
1.050
0*962
0 .915
0 .875
Eate constant 9*00 x 10 13*88 x 10 (niiu )
— M I III iiinnimiiiim—i«w— iiiiinnniniin n immmmmm minim n minimi mm i mum n i n mi
Mg* 13* Curve 3* Curv« 4*
FIG. 14
ACTIVATION ENERGY
en
4
2.0
1-8
1.6
1.4
1.2
10
0-8
0.6 270
-©-i-
27.5 28.6
| x 10
28-5 -»-0-
29.5
87
3* a © 1 e - 30O£? .
f@Dporature dependence of th© reaction rate*
/ p r 9 ^ * 33«33 « 10*4!!,
Keoperntur* 363°K 36&°£
5?tD©(niii0*) i O ^ r ^ D ) a+ log^f j?^ %0A/^T^J{U\ G+loeffr^lJ
0
10
20
30
40
60
60
70
80
90
100
Hete constant
S3 . 53
B6.7S
22*13
17»70
14.07
IS . 10
10.43
8.98
7.80
6.61
5.72
17.66
U822
1.40?
1.345
1,240
1.17©
1*083
1.018
0.053
0.89S
0.013
0.758
* 10~3
33.33
26.32
83.71
16.15
13.60
11.53
10.72
8.07
0.78
8.48
4 .06
84.00 x
1.522
1,420
1.374
1.208
1.133
i . o e i
1.030
0*907
0.831
0.734
0.603
10" 3
(sin. ) * I M M M N M W l M I M M | i « W i < < | ^ ^
£l£ . 13. Curve 5 . Curve 6.
83
By mrrlstg tfie eoiteesitrstios of ©odiaci ^§#©iiXorat$»
tfee icmle etr©%fcls sf tfco rewtoticHi ®&%t®m w©s «o8olato6«
f&o otiter resetion eoa<ions w®re eaintslneQ Monti ©a;U
A alight i&ereMre la tti© irate Axmstont niite in&vm&i.n&
Ionic strength m© ofeoeyvtig and l e uiiowi fcelow*
FIG.15
DEPENDENCE OF RATE CONSTANT ON IONIC STRENGTH
0 10 20 30 AO 50 60 70 80 90 100
T IME(m in ) •
83
f a fe re * KOTJ*
Bffeet &f $ml* strength on t&« rate «JP oxidation*
?*gt3t*?&2*l°Cf J^H^O^J m 4*6Mf ^"Wtyzla ©eifiJPa 0*8H|
£$v^f m 26.66 x KT*tU
CQt&xQ^J o.<m o*sn
i©aie. 4#so o#on strength
MiMlMWlMiMttNat tWI^^
Slcie(nliis.) 104^i»^7Ctl> 4«4o^ir ? i7 ' I O ^ S S P ^ E ) 4*lo^*?1?5 r
mi.iiinmii ImMii
0
10
20
30
40
80
60
70
80
90
100
26*66
£©•48
24.36
23* 8&
22.64
21*36
20*06
18*76
17.78
17.38
16*60
%*4m
1*406
1*386
1*871
1*334
1*329
1*302
1*273
1*2S0
1*240
1.220
2 6 . 6 6
2 0 . 2 3
Sip1* 7 Jc
22*80
2 1 , SO
19.77
18 .83
18*23
17 .70
16 .06
1S .41
1.425
1.402
1.375
1*358
1.328
1.296
1*276
1.263
1.248
In 206
1*188
Eat© coaatrmt 4*8 at 10~3 5*75 at 10~3
(©in* ) mmmwmmmmmwmmwmmmmmxmmwmmmmmmmmmmmm»mm\ir\i m in i i n u m w i i i i — w — m m n •mini m mini i rmtmmmmmmmmmmmmmlmK
Xln. 18* Carv© 1* Curve 2*
99
2 G b I © - K M f l l .
Effect of ionic strength on the sate of os&a&tioiu
S?esp.75£.l°C$ £\&>^7 - 4.SH| ^"Butyric acid J " * O.S f
S ^ 7 • 26.60 a «T%, « M — m m i WHII mini w w w — — w i n miiiimn i ninimin *t*mmmmmmmmmmmmm*m*mmmmm'immmmmmmmmmmmmmmmm*Mmmii*»mmmmi^^
C&®$l°4r7 *•<»* 1.511
Xonie^ 5.60 6»0H ©irongtfe
SisetialiHi.) i O ^ r ^ n ) ^ l o o S S r ^ »\j3e'5 r(tJ) 4*los£Srt?j7 4MwlM«*Mi*rt|ri*«tM*«V«|M
0
10
a) 30
40
60
60
70
80
90
100
26.66
23.41
23.44
21.67
20.60
19.50
18.32
17.06
15.63
14.02
13.67
1.425
1.405
1*570
1.336
1.314
1.200
1*263
1.232
1.194
1.174
1.136
26.66
25.00
63.44
21*72
19.67
18.62
17. 68
16.60
14.96
14.32
12.88
1.420
1*398
1.370
1.337
1.294
1.270
1.246
1.220
1.17S
1.156
1.110
Eat® constant 6*32 x 10*3 7.10 x 10~3
(Eln.*1)
Fis* 18. Curve 3. Curve 4.
91
EfJtoet of ionic streagtk as its« ttatc ®£ ©sidatiaa.
5eiap#7&t*t0Ci ^f*HgSO -/w 4*83$ £"Wty:rio oa&jBjm 0*5H;
^ ^ » *«*«6 * i o r % .
Xeal<» 6*Sn etrencth
?tD0(i3iao»> 1 0 4 £ d r ^ n ) ^ l o G ^ r ^ J
0
10
m m 40
80
60
?0
60
90
100
26*66
£S*00
S3* 22
20 .60
18 .83
1?*$0
16* €0
14.00
13*33
18*85
10 .13
1.425
1.398
1*366
1.314
1*278
1.243
1*221
1.175
1.125
1*109
1*005
Eat« constant 8.22 x 10**3
( Ida** 1 )
H*T* IB* Gusw* S*
FIG. 16
EFFECT OF ACETIC ACID ON THE OXIDATION RATE
0 10 20 30 40 50 60 TlME(m'm)_
70 80 90
92
T a b l e - XXXIX.
2«£L»eno» of eeotis aoid on the rata of osdt&atloa*
2cnp.f©£#l0C$ CtytofJ* 8»0Hf ^ffeutyrlc ©cifij^- 0*S£$
^ p * ^ • 20.66 at t lT%.
• • • • • • W l
acia NIL. 0.2H
SicoCatno.) M4£8r??J(n) 4*1©$$*?!7 i 0 4 ^ r^7 t t : ) 4 * 1 0 ^ 1 ? ^ •MMMMMMMMWItlNlfttM*^^
0
10
£0
SO
40
SO
60
70
80
90
100
26*66
54*14
21.77
10*44
17.37
1S.76
14.15
19*44
13.02
1S.S6
11*86
1.488
1*388
i.sst 1.208
1,240
1*107
1.160
1.1S8
1*114
1*008
1.074
S3* 60
ni.oo 20.58
18.48
1£*78
15.30
14*00
13 . 26
18.88
12.00
11*86
1#4£S
1*340
1*313
1*266
1.SS4
1.104
1.14S
1.1S2
1*109
1*080
1*051
Sat* constant 9.08 Jt 10~3 9.70 x 10 k~S
Flf. 18* Curve 1* Curve 2*
93
S a b l e «• *£&»
Influence of ocotic eelfi on the r a t e of os&Satiorw
«ecp«70£,l°0t "BgSWS JT « S.OBf ^ t i t y i f l c a d d . / « O.SHf
^ r ^ 7 * 28.60 a KT%*
ChvMQj &*m o.7n ael€
lllimillll llllllWMIWWIMMMWWIWWWWWIIM^IIllllllMlllliail^ W W I H I I r i | |HIII|IIIII«HIWI>H1«|>IHIIIIIMI»IIW I Ullllilllllllll I W » M « I W I < « — » « » » — «
fioeCiaiiiG.) 1 0 4 2 j y ^ n } ^ l o ^ r 1 ^ 104^r1 ,j7 4MAC Z ^ ^
0
10
20
SO
40
60
60
70
60
90
100
Hate
26.66
£4.65
20.87
18,08
10.81
15.44
14*80
15*44
11.87
10.92
10.34
constant 10.SO x
1*488
1.388
1.311
ueef 1.SS5
1.188
1*170
1.127
1.074
1.038
1.015
10"3
86*68
83*48
20.20
19.03
16*64
16.20
13.42
IE. 18
11.66
10.78
10.04
10. 52
1*425
1*370
1.305
1*270
1*221
1*181
l*l£7
1.035
1*088
1*033
1*001
% 10~S
(rain. "**) M M I M W M I M M I
Jlg# 18* Cur?© 8. Curve 4*
94
2 & to i e •» xsau tmfmmvw &f ©#e*ie n©iS ©a t&e mrfLfimttm rat##
?et3p»?0±.l*es i f ^ O ^ J * « g.OHf £ l f c i i y r l e « e l 4 / « ^ • S H »
B«i>ii.r. IIIIII.IIIIHI.IIIII •IHUI.IIII ii. • i ii nuiiiinii iiiiiiiiiiiiiMK.iifiii i.iiii m-IIII niimm mum in mi i m •inninriiiiii n j HI mm HI—«iwiwwii>Tiim—••nan-
«MMMMM>wwiMam«aMwwwiiia^^
fteCMKM »*(gRp127ta) ^ IO^SSP1^ M*ffity **i»cffi?lj iiniiiiiiiiiiiiniimiiii uinmini—II»I I IMM«I«—MII I IHI I I I I I .mi ii in imiiiiin, i i mi im. i .1* . .»• .——»»»—>——««I I I I I I i IIIIIHUPIIUIH —mi »imnirmii»i>iirni m mmmi
0 26*66 1.425
10 C3.34 1*300
01 20*71 1*816
30 ta *© i i *«6*
40 1#*4S 1,810
SO 1S*0S 1*1VS
so IS»M %*tm
70 12.13 1,085
80 11*40 1.0 CO
00 9*8? Q*994
100 0*12 O.teO
Hat© ©onetsat 11*18 % 10~3 11.84 * 10~3
( p i n * } 'inn II mmmmMmmmmmmmm0mmmm/mmmmmmmm»mHmmmammmmmmmmmiimmm«ii\ i n n H M W — W — « m u n » n » ' i « — — w o — — « — i w i i w » » <
H^» 16* Curve §* GmrvG 6*
2C.S6
t l * 9 S
m*m 13*85
15 .98
13*81
1C.S5
11*5®
10.62
9 *S2
8 , 4 1
1,425
1*342
1*313
1*261
1*80S
1*140
1,093
1.064
l*Q2£
Q.9C&
0 .925
3??tH>I-<?S mm ITAPStlC ACID
.Oydcr fo Charon^ ?oia;
2he progress of tfco reaction was followed by
an t&isFHtioal tsottiod 4e&eslbed for propionic aa«
butyr ic a d d s . The plot of lo# c&ronic aeifi eoaccR*
fcrstlon Vo t ine gave goofi ©tralfthf l inos ond tfeo
©lopes trare naod for tkt* detonainotloR of f i r s t
order ra te constants. 2abJ.cs given boloe record" the
f i r s t order aoooMeuoo of tfeo reeotiou on cfcrodc
aeifl concentration.
FIG. 17(A)
DEPENDENCE OF RATE CONSTANT ON CHROMIC ACID CONCENTRATION
10 20 30 40 50 60 70 80 90 100 TIME ( min ) •
96
? 0 b 1 e - XLII.
Depo-nacnoe of ra te constant OJI eStrersIc; ®cld concentration.
^OfeywalcJT 166.67 x 10*% 66#€6 x 10*% aelfi
SineCfitiis.) 1 0 4 # r ^ ! l ) 4*lo^B*yj7 lO^Jr'J'te) 4 ^ $ ^ * ^
0
10
20
30
40
SO
a) 70
80
90
100
F*ate
160*67
166*04
187*82
152.. 88
149*72
142.80
137*70
129*87
123*86
118.SO
112*86
constant 4 .88 x
2 .221
2.220
£.197
2*183
2.175
2*134
2*130
8 .113
2*003 "
8 . 0 7 1
2*058
1 0 ~ 3
66.06
63.90
66*82
61*04
60*42
©6*10
52*32
49*48
48*06
40 .17
44*60
4*34
1.823
1*003
1*798
1.791
1*773
1.749
1*718
1*694
1*681
1*664
1*649
X 10~ 3
(Bin.*1)
Fig* 17(a)* Curve 1* Curve 2*
FIG- 17(B) DEPENDENCE OF RATE CONSTANT ON CHROMIC ACID CONCENTRATION
o en o •
0 10 20 30 40 50 60 70 80 90 100 TIME(min)—»-
9?
T a b l e » 11*111.
SepeaSei&ee of rat© constant on chroKic a d d eaaeattratlQH*
Se3p.7S2.i°C§ £"feg304-7« S.OHf £"?8le*!lc e c i a . / * 0 . 1 0 .
^CiilJOHic,/ 41.60 a 10~% 33.33 X 10*% cc3d
MiiMfi^liUDIWIWOWlMII
f taedstao.) l O ^ r ^ C U ) 44to($tPf %Q*$TmJ{m &+l*f?$t^J
0
10
20
30
40
50
60
70
80
00
100
41*66
40*24
38 .37
37 .42
35.34
S3* 6S
32.07
31 .06
29 .74
28.92
27 .88
1.610
1.604
1.S8S
1.873
1.848
1*306
1.506
1*492
1*473
1.461
1.435
£ 3 . 3 5
31 .74
30 .30
S9.47
88 .17
26 .98
25.!? 5
23 .46
22* IS
21 .00
19*93
1*§22
1.601
1.461
1*469
1*449
1*430
1.402
1.370
1.34S
1.324
1*298
Rate coaotaat 4 .23 it 10*3 5.12 % tfT3
(csiiu"**) MMMMWHUngt
I lg* * ? ( a ) . Curve 3 . H f . 17(b) Curve 1 .
98
T a b l e • 3XST*
dependence <sj ra te constant on chronic acid concent ra t ion ,
<2mp»7$£«l®Gi ^ g S O ^ J T . 6.0K* ^p?©i«ric ©eld^* 0.112*
^Chroa ieJ^ ST*?? x 10~% 20*83 * UT*a acid
flaetisiBs*) l O ^ r ^ B ) 4 * 1 0 8 ^ * ^ J O 4 ^ ? ^ B ) A+Uqffi!**?
0
10
so
30
40
60
SO
70
60
00
100
27.77
26,86
25*78
25.35
23.76
25.94
22.19
20.87
20*05
16.07
17.02
1.443
1.425
1*411
1.403
1*370
1*360
1.346
1.310
1*302
1.271
1.253
20*83
10.92
19.05
18.87
17.10
10.45
15.00
14*82
14*09
13.37
12.01
1*318
1*299
1*280
1*209
1.234
1*216
1.192
1.171
1*149
1*126
1*000
Hate constant 4.47 at HOT5 8.20 x 10~3
(uln*"*1)
Fin* 17 (to)* Curve 2* Curve 3*
93
f a b l e - - Sit?.
Dopemdrmc© of r a t e conotc.nt on ebrmsiQ a old concentration
f©np.fS^.l°0| ^llgSO^JW ©.OHt £Valoi!ie soiflJ% O.lM.
£"Cbr01310^7 16.66 x iO~% - S8l£ MMy»MI||MWI^MlWMM»*^*P»«***«'lM«M»
flooCam».} 104#r^7(n) 4+log^r^7
0
10
20
30
40
60
60
70
60
90
100
16*66
1S.96
I S . 36
14.76
14*00
13.S7
12.44
11.53
io.es 9.87
9*14
1,221
1*203
1.136
1.170
1*146
1.122
1.094
1.062
0.028
0.994
0 .961
8ete constant S»i?2 x 10"3
(&ia.~ *)
H<> 17(b). Curve 4.
103
Qrdor i n gufrnfrr^te-
Het© constant© a t different suootrate
concentrationo wore obtained ojr varying valeric
acid concentration kcopins othor factors eonotont.
fise f i r s t order dependence on attbotroto W&Q inferred
from ttio plot of rote constant Vs. otiootr&te concen
t ra t ion ©fcoro n otreigni l ino passing thron^n the
origin mm obtained* £n<* ©lot io ottotsrn in figuro id.
FIG.18(A)
DEPENDENCE OF RATE CONSTANT ON VALERIC ACID CONCENTRATION
1-55 h
1-30 0 15 30 45 60 75 90 105 120 135 150
TIME ( min ) „
1 0 1
$ a to 1 o - 3&7I*
Beper^cnce of ret© eoaotaat oa til© corieentreticm of valer ie ncid.
2s£sp.7&-"*l°Ct £Tlg804„7* 3.0Hf Sv^m 33.33 * 10~%.
^"VaUric j r 4,0 x 10"*% 8.0 at 10**%
fiB^Cisiii8.3 i04^tTr^7Cia) 4 a o g ^ e ^ 7 i 0 4 ^ r ^ 7 ( O ) 4 * l © ^ r p ] 7
0
15
30
46
60
m 00
103
120
135
ISO
S3* 33
31 .90
31 .43
30*84
89*87
28*86
23 .45
E7.7?
S7*23
26.55
26.04
1,522
1.S03
1.49?
1.485
1.478
1.460
1.454
1.443
1.435
1.424
1.418
33*33
31 .08
31*03
29 .93
23 .92
87 .97
£7*13
26*64
23 .97
03 .17
24 .48
1.622
1.304
1*401
1*476
1.401
1.446
1*433
1*433
1*413
1*401
1.368
Bat* conwtant E.03 x 10*S 8.66 z 10~3
(ala.** *)
Fig. 18(a). Curve 1. Curve 2 .
FIG.18(B)
DEPENDENCE OF RATE CONSTANT ON VALERIC ACID CONCENTRATION
0 10 20 30 40 50 60 70 80 90 100
TIME(min) *
102
Dependence of m t e sossi^at OR *&e s«»s®atr&*ioa of Tr>lerlc t*eld.
2®3p*^. l°Ci Z ^ g S O ^ w 5.0E| # r ^ j 7 « 35.53 X Stf"4!!, .IWlrtlMMl • II li| I I I I I II I! Ill II ill I l l i lh l l IMIIill IliHllllllli i l l l ini in .11 ilpi.MiiWi-.II.MII II liillllM1HIII.il •••i l lWll<Hlll l»>Hilim>IW«W»HW«»«»W«M»M»M
^iTaler ioJ^ 6*6 x iO*% 10*0 x 10"% aeid
SliaeCislits.) 10*^*^7*13} 4 * X O ^ J T P ^ 7 l O ^ g f r ^ H ) 4*log#f*'j[J7
0
16
30
4a 60
?s 90
HIS
120
135
150
33.33
51.16
23.74
28.80
27.59
25.96
24,94
25.99
22.98
22.02
21.20
1.622
1.493
1.475
1.469
1*441
1.414
1.59?
1.380
1.561
1.342
1.326
55.55
51.74
29.29
88.4?
27.17
25.95
24*25
£2*48
21.08
19.95
19.02
1.522
1*501
1.466
1.454
*#^**(Wi
1.414
1.584
1*551
1.525
1.299
1*279
Rate conetaat 3.00 x 10~3 5.5X3 x 10*3
< ffllfU )
Fie. 18(*) Ctinre 5 . Elg. 18(t>) Curv* 1.
FIRST ORDER DEPENDENCE OF RATE CONSTANT ON VALERIC ACID CONCENTRATION
FIG. 19
200
180
160
140
120
100
80
60
40
20
0 ooo o J2-
10 15 20 25 30 35 40 45 50
10* [VALERIC ACID] -
103
2 a b 1 m « X&fXXX*
Dependence of r&fco constaat oa the eoac cat r a t i oil of vol er ic acid.
so ld
5t?li3©( c d n s . )
0
10
SO
30
40
30
SO
70
SO
90
100
20 .0 at io-%
^ 4#J^7CK) t+toggr***^
33 .33
30.7B
26.68
2G.84
24 .50
22,07
20*33
IS* 2S
16.21
14.30
12 .84
ftsto constant 0*07 ( B i l l . * 1 )
1.3S2
1*48?
1.43?
1.428
1 .301
1*343
1.308
1.S61
U21G
1.161
1.001
x 10" 3
4 0 . 0 X 10**%
lo^flfip^u) 4*ioe#^
33 .33
30 .23
27 .19
26 .83
23 .13
20 .55
17.64
13 .43
13 .21
11*70
10.56
18.60 a
1.5 £2
1*430
1.434
1*408
1.364
1.312
1*246
1.188
U 1 S 1
1.068
1.083
: 10~*
Eig. 18(b). Curve £. Corf* 3#
101
Variation of ra te conotont with acidi ty
The effect of hydrogen ion concentration on
the oxidation ra te »aa studied exactly in the oaise
Banner ae in the oxidation of propionic and butyric
acid. I t i s seen froo tab3e LI I tfiat a t lower ac id i
t i e s the oxidation re te veriee almost exactly aa the
square of hydrogen ion concentration but in oolutions
of higjj ionic strength and high acidity* the reaction
velocity changes at a ra te somewhat greater then that
required for second order dependence. However, the
plot of logarithm of ra te constant against nodi fled GHpn acidity function H« • log • ' yielded a otrai/!ht
l ine but the slope was quite high..
FIG.20
ACIDITY DEPENDENCE OF THE OXIDATION RATE
0-4 I 10 20 30 40 50 60 70 80 90 100
TIME(min )
105
7 a fe 1 « « XldX.
Acidity dependence of tfco oxidation rate*
£"V«*lerie aeifiJT. O.gSf £?**??* 26.66 x t®~%*
•iwiii m u m Kim mimnmi I H ia i • m i i i i i mmii m urn mim' m um inmMmmmmmmmt^mt^imt^mmm^mmt mtmiimm,mttmmMv tiiti\niuilinmmmMmmmmmm
StastBliio.} l O ^ r ^ C M ) 4 # l o | ^ r ^ 7 104^5r^7tE) 4*1© n ^ r * ^ •MMMMMMM
0
10
so 30
40
§0
60
70
80
90
100
£6 .66
£©.03
25 .55
24.87
24 . S5
24.46
24*02
23.18
22.92
£2.65
22 .33
1 * 4 3
1.41B
1*407
1*393
1*301
1.388
1.300
1.363
1.361
1.30©
1.349
26 .66
2B.G6
25 .40
24 .50
04 .13
23 .06
23 .10
28 .60
21 .90
81.17
20 .16
1.465
1*409
1.404
1.390
1.333
1.377
1.364
1.354
1*340
1.323
1.304
Eete conotant 2.04 * 10*8 8.80 s 10~3
(tain. ) — — — * — — — — — — - — • ' — n • •» i i i i in 11 ii 1.1 n i um ii i i i .a. i i..m . j . ..i i . .JI.LH. ... i i
f%E* 20. Curve 1. Curve 2 .
106
S a i l © - %m
Ae£4ity depoadflnae of tl*«s oxidation mfc#*
£"Ynl«i3lc ©ftldJ'W 0«SE3| $^J*> »«*«« * I t f 4 ! .
£ l * a S % / 4.011 4*iH' «—«»«»«•—•—WOT mill iOT»l»«»ll«»«tl«IIIM»l«««»«»«ll»»WI ^
2to®(s3ias.} 104#r^Ctt) M e # r ^ loVjkT&tfl) toV»eff***p
0
10
so so 40
60
60
70
80
90
100
26.66
£0*71
24.43
£5*93
£3*14
2 1 . * *
20*70
20.37
l$ ,77
ie.72
17*62
1.423
1*411
1.388
U978
1,364
1.336
1.317
1»3O0
i.2t#
1.272
1,24@
26,66
28.71
24.44
23.22
21.47
20*30
10.05
17.S7
16.53
13.23
14*10
1.425
1.410
1.388
1.3S3
1.331
1.307
1.270
1.252
1.219
1*183
1*310
3&t€ con©tent 3.88 x 10~S 6*25 x 10~3
(ntn. ) imtmmm>ttmmm%mm»mmmmmn n0Hmmmammmiwmmm**i*mKMmm
Fig. 20. Curve 3 . Curve 4 .
107
Aeltilty 4©pen4eaoe of t&e ©xlfistioa rate*
tep.7S2.100$ £ 1 ^ 3 0 ^ • £l^IS0 4 J r * 8 6.0Mf
^TVaiorio a d a j ^ O.SSf ffr^Jm 06,66 x 10*%,
^ l i g s o ^ s.ois s.sn
fimetjaiR©,) l O ^ ^ H ) 4*l»|#rf][7 10 ^fc^O Mazffflj
0
10
20
30
40
SO
60
TO
80
90
100
26,66
m.m 28,44
20,76
18.73
16,83
14,83
13,00
11,48
10,28
9,23
1,428
1,407
1,370
1,317
1,272
1,226
1,162
1,114
1,087
1,011
0,968
26w^&
24,26
21,20
16*30
12,10
9,92
8,07
6.76
8,01
8,68
2,18
1*42$
1,888
1,326
1,212
1,088
0,998
0 ,908
0,030
0,700
0,866
0,889
Hate constant 9.02 x 10~3 11.32 x 10" (lain.-1)
Hfi* 20, Curve 8, Curve 6,
10
Table - 21X*
Effect of acidity on the r a t e constant
(U) (nin.-1) C\& 0&
-fruin—in r " r n—" r*-J ' ' 1—11 v • it r » irr r r r • n r n - -—-rr—- — — , - • —
3.0 9.00 2.04 0.68 2.26
3.5 12.25 2.80 0.80 2.28
4.0 16.00 3.88 0.95 2.42
4.5 20.25 6.25 1.38 5.08
5.0 25.00 9.02 1.80 3.60
5.5 30.25 11.32 2.58 3.74
10J
Boaofcloa «ss »tu41eA tracer ifienticcti conaitiono.
Actiir&tiOK eaorg^ we© calculated graphically - end
other t&eraodynsmio puretnotore B?er© calculates fron
the f onaaldft eemtloae^ eesllev* fh* v®la©s ©£ t»»
AH* ana AS* were fo««g to b© 20.? l e a l ,
20,05 Kfial «n< ~19»t eu respectively* ffce oboorva-
t loaa a t varlmm t ^ p o r a t a r e s &r© presented fcolow*
FIG. 21 TEMPERATURE DEPENDENCE OF THE OXIDATION RATE
o
O ~+ «4
0 10 20 30 40 50 60 70 80 90 100
TlME(min) »
110
? a h 1 ® * HXI*
?«ep<iratiixtt 4©«eR<!en©© ©f tlto reseat! on ret©*
^HgSO^^TW S.O&t £"Velerlc ooI^JTw 0#2K|
Z&tf^ « 26.64 x 10*4!!. M M , , . , , . . . , . . , . , . . , , I . I . . I . L , I M , . ,i, • , i , ^ w , , ^ , r » . . , W l . . , ^ i i u l , . . . l . a , » . . , . M I , l | l . l l . , . l l < , . l . . l i . . , . . . , l . i l . l l i . , , , i. . . . , . , — .
feoperaitir® $43°k S40°K
fiootisijie*) l o ^ i r ^ e ) 4* ioc^^7 t o ^ r ^ c n ) 4*ios,i!!P^1Sr
0
10
m m 40
so €0
w 80
90
100
Hate constant
26 . G 6
26*06
24 .66
23 .91
83 .33
<£**5*i6
20*43
« 9 * l } £ .
17.79
16*95
16*84
5*14
1 * 4 3
1.410
uzm 1*378
1.3C3
1*340
1*311
1.886
1.S49
1.229
1*200
it IflT8
2G.66
26 . EG
£4*S8
23*58
22*43
*C * # <£*#-
19.63
18.14
16*44
13.30
11*36
6*14 x
1.425
1*407
1*390
1.37g
1.3E0
1*326
1.294
1.25S
1*616
*» *«J4
1.036
10* 3
(al i i . ) "i • • HI i n i . I III . III . n • m
H&* 21* Carv® 1* Cnnre 2*
I l l
• S a b l e -* M?»
?®2perat«r# dependence of tho r©acti<*ft rate*
temperature 333°S: 5S6°S
2incCQt»0.} te*&**jfm 4 * 1 © G ^ ^ 7 10*#r^{£5) 4 + l e f ^ r 1 ^
0
10
so 30
40
SO
m 70
60
90
00
2C-C6
26.55
24,04
83*09
£0.93
19*89
17* 98
16.83
18.83
11*97
9.92
1.425
1.404
1*881
1.363
X.3S1
1.298
1.050
1.200
1.141
1*078
0.996
26.66
26*18
21.22
18.86
15.67
12.48
9.84
7*81
8*60
4 . 6 1
3.74
1*428
1*401
1*326
1.278
1*198
1*096
0.995
0*864
0.748
0*664
0*872
Hate cofistaat 11.81 x 10*3 80.34 x 10*3
Fig* 21* Canra 8* Curve 4*
FIG. 22
ACTIVATION ENERGY
290
1 4 — x 10 T
112
Temperature depcndeno* of the r e a c t i o n ro t s*
C&2SQ4J* ©.Out /"Veler i© aeiaJPU 0.m$ # « • i 7 * £6*68 ir 10**I3*
$**81*©**ittti?*s 363% S6B°E •M»»|«»l«»ll««>»«»^»M»»llll| • l l l l l l l l l i l lt l l l l l i i l l llliMWJWaMMMWMItWMWl Umiimmilllll Kill II I IL«IMI»WtlWWIIII I«ll«III I IW»IIMIII»iMM»«IMMI»^^
2iis©(£&»*,} 10*jfl&^8) 4* l0Q^'5 r 104##??7W 4* l0^fr^7
0
8
10
15
SO
25
30
25
40
46
50
06*60
25.32
24*11
82*46
20.51
19.03
17.0s
18*B8
13.16
11*83
0*77
1*428
1,403
1.382
umt 1*312
1.230
1*231
1*134
1*110
1.061
0*090
26. 6G
24.60
22.05
10*03
15.20
11*06
7*19
6.27
6*00
4*02
3* SO
1.425
1*302
1.343
1.275
1*104
1*070
0*036
0*797
0*707
0.604
0*839
Sate eonetaat 27*63 * 10*3 40.68 x Hf 3
(Bin.**) • • • I H I I H I H inn n i l MI urn . i n tin mil — u p — M I . I I I I I . H I I llmmtmmmtitmmmmmBmmtmmmmmmmmaim+mmmmmtmmmummm
Fl0* 21* Otirre 5 . Curve 6*
113
I onto strength of the ncdlian wso verled by
Gdfiinc vsfftmis ecouato of ©oaiiaa f»er«!iXti*ate« &
slight ingress© to the ret© ©oaetsat with Ax&xo&Ui&
ionic etren^th. mm £oimS» Sbe Sato ©re gives in the
following tables*
FIG. 23
DEPENDENCE OF RATE CONSTANT ON (ONIC STRENGTH
60 75 90 105 TIME(min ) -
135 150
1 1 4
J e U c - E7X*
Bffeot of ionic Btrength on the ra te c o n s t a t .
llirwilllllll initlWWIWlMpWIMlMIWWMMWrMtWIWWW^^
Ionic. 4*81! S*0K strength
Si©e{iS3i*ia*3 l O ^ J r ^ t l S ) 4* lo^5» V 5 r l O ^ y ^ S ) 4*a»£^Trv5r
<MMM«ainMM!«Ma*>iNiawHMiMW^^
0
10
so 43
60
78
90
105
ISO
135
160
£6.66
24.61
23*14
08*40
21*10
19,74
17.80
16*50
15*46
14*44
13. 80
1,425
1,391
1*364
1*530
1,325
1.205
1,250
1*817
1*189
1.159
1.120
26.66
84.30
«5*£f| f 4fcr
21.32
£0.82
19.20
17*80
16*03
14*87
13.46
IS . 11
1*425
1.389
1.356
1*353
1*307
1*287
1.250
1.205
1*17E
1*1££9
1*083
Hat* constant 4.82 x 1(T3 5*37 x 10*;
(a la .* 1 ) M I I H I I M I I I I I I — — » — » w » » i • I I I I I I «mii muni — — — M M — — « I I K I •• • i n i w w w — — — — n U M I — — —
Fig* 23* Qarw 1* Caw* 8*
115
P a b l o - LVII.
Effect of Haste strength «a tit© ra ta cone t e n t .
*©srp.7s£*l0Cf Cty^+7m 4*8tS$ ^ V a l e r i e aciaJ'W 0*1K|
Sr^m %&*$$ it icr%* « M » — — II Hill • • I I I IIIIW—«•—M Xi l l i l l i l l WWWWWimwDWIIWlllliilil liHHini nil IIW—MMW>1HIII.MIII»IH»»1—w IMIIIIIIHIM II
£%dHXQ^J 1.00B 1*80 i»n tin mm i i i • im> ii umiii mn in r iiiiinun M — w i i i i i i » m n « » i i i n i i i i i i n iiiiininiiiiinmiin—mm mm i ri mimiinmw
t«s*ie_ &*mn 8.0S strength
H*^MftMNMH«mlf«
f*»©{a*a0«) I O ^ J T ^ B J 4*10^35?^ l O ^ y ^ C H ) 4*lo^JTr^7
0
IB
W
46
CO
75
90
108
ISO
155
160
26,66
£4.36
22.91
£1.15
19.54
18*10
17,08
15*57
14,84
13*00
11.56
1.423
1.386
1*060
1.325
U2W
1.857
1»23S
1*192
1*153
X * 9MM9
1.063
86.68
35.51
2P..52
SO* 45
10*74
17.56
15*85
14*55
15*53
IE* SO
10*88
1*425
1*585
U5SS
1.510
1.272
1.239
1*199
1*185
1*155
i.oto 1*054
8*t« constant 5.48 * 10*S 8*80 * 10*3
(Bill**1)
H&* 25. Cunrt 3* Carve 4*
116
£ a % -1 -» - * -fiVXH**
Bfftot of ionic Atrtngtb on tfee r a t e eonntont.
$r^?m B$*«0 x 10*%. < M « > W I W H » « » « I P I I I » « I - I I I I I I I I I I I I I I I I P W — « w m i i i ii i i m i i « » « » ^ t » M ) i i « — I I M » I I I I I » I I « » mrni«iiii»i»iiii«iini IIII.IIH w mm m i n « »
**»eC»n».> u ^ ^ t i o 4**>e&?*r
0
t §
SO
48
GO
?S
90
105
ISO
135
180
26*66
24.43
22.35
W»%B
18.35
la.fg 15.40
14*04
I M S
11*40
10*03
1.425
1*308
1*340
1,305
1.263
1.223
%»m 1*147
1*104
l.OSfr
s*oos
Bat© constant 6.86 * 10~s
C^Ltt.**l>
Fig. £3* &»***• 0*
FIG. 24 EFFECT OF ACETIC ACID ON THE OXIDATION RATE
15 30 45 60 75 90 105 120 135 150 T l M E ( m ' n ) "
117
InSnnmcQ of aoctio aoifl cm tho oxidation r a t e .
D#1H ?^ * ^ I * * P ©•05
*4/srJ?X *4j»jn- J*I« SfcoeCistas.J a o ^ ^ J T t a ) 4 * l » $ $ e * y l O ^ f l f i f ^ a ) 4*I©affir;!7 • M W K M M M W M a
0
15
30
46
m 78
90
103
ISO
135
160
£6* €6
24*30
23.48
£1.60
19.56
18.02
%&*W
15.24
13.63
12.45
11.20
1.4£B
1,387
t»$?0
1.334
umi 1*255
1.223
1.1S3
1*131
1.095
1*043
£6*6$
24.90
25.08
21.04
m*m *?•©&
15*92
14.10
12.00
10.52
9.26
1.425
1.396
1.363
unzs 1.283
1.243
1.202
1.149
t»078
1.022
0»#67
Bat* constant (•!&• )
< M M M l « l M a M M ) a a i >
Hg* 24*
6*26 X 10 . • »
n C I M w i l u H « i <fcilff»iWIIMh<««<tWWil^WW<BW»lWW|>Wi
Carre ! •
,*»3 7*88 X 10
Curve 2.
118
Inflatmoe of acet ic acid on the oxidation r&*©»
M W W i n nmriinim i iiiiMiiiniwiii>i»iiMii»»«»iiii»wiiii«i»i»«»i<i»^^
acid
fiaeC«iitt*»l I O 4 ^ 1 ^ ^ ) 4*iQ$jp*1?*7 t o 4 ^ ^ * ) a * *©^*^ n i n m n n m m n «i I»»W»—^«»I»»— ti'iiin »r" iiiaw»i<«»»«-«»««ii»i«»iiininm«>i-w»»w»«»Miii»ii-iiii««iiII»T«»II»III»I«— I I I H I M H I I I i mi i . i i u I » I » « I » I I I » < I I I » I immiinimn H I HIIIIIIIIII
0
15
m m m w m
100
tm 135
150
26.66
24* l i
32*40
20.08
i?*f0
l o . l l
S3»«?
le.os 10.66
0*96
?.8X
1.426
1.582
1.360
1.302
1.248
tmWBT
1.135
1*000
1.0C8
0.952
0.093
26*6$
23.96
21.69
19.00
16.64
14.45
1S# 48
U**?
9.52
0.43
7.44
1.425
S.379
1.336
1.278
1.221
1.160
1.094
1.040
0.970
0.926
0#8?g
Rut* ooaatnat 8#44 x iCf3 8»88 x t<T8
Fig, 24. Curre 3 . Carve 4*
119
s * b i * - m»
Influence of acetic ecid ©n the oxidation rate*
0?*^?* 28* W X 10*%*
ccia aMMnMPWtMMIaaMM^MUMMMMnill lM^^
SUtt(ttta»«} i O ^ s r ^ H j ^log^Tr11^ 10^3&V5Fln) MOBS/P***/ »wmwnmi
0 26,$6 1.425 26.66 1.425
15 2$*m 1*168 23.05 1.363
50 20.91 1.320 20*64 1.314
45 10.24 1.2G2 17.90 1.253
GO 16,20 1.209 14.51 1.161
7B 13,90 1*149 18.48 1*004
90 IS. 10 1.082 11.20 LOSS
100 io.si i*oai 8.9i o*9so tm 9.05 0*900 8.03 0.905
135 8*26 0*917 6.40 0*800
100 6*80 0.032 4 .81 0.682
Rat© constant 8.SS x MS*3 0.97 x 10"S
(Rla.*1)
Slg* 24. Curve 5. Curr« 6*
C H J 1 P I B R I I I
O I I ^ I C S OT CHMTIOH OP BRJJICBKB CHAII FAT2T ACIJ2S
120
IHTR0OTC2I03
The knowledge oJC the Influence of s t ructure on
react iv i ty lo not only important frota synthetic point of
vion but also represent© en inportant tool in the study
of reaction taochanieo. ?he dependence of the oi&detion
ra te on carbosryile acid s t ructure has not been inves t i
gated systematically. I t cos.therefore, thought worth
while to study the effect of branching on the ra te of
oxidation of fat ty ac ids . For th i s purpose, otudies on
the oxidation of iBobutyric, isovaler ic and pival ic
acids by chromic acid were carried out under different
experimental conditions.
She oxidation of carboayllc acid© containing 128 te r t i a ry carbon a ton i?as studied by Synons and Tenyon .
•Ehey obtained hydroxy carboxylic acids from the corres
ponding branched chain carboxylic acids by uslnn
potp.ssiun pernmnpanate in concentrated t ikal inc solution,
w> cn(ci i 2)n cogH ^ T? n c(oo)(CH2)n cOgii.
The reaction nae slot? in dilute airline solution even
at elevated temperatures and resulted in the degradation
121
of acid. In concentrated alkaline solution, the reaction
was faster and proceeded at roon temperature leading to
hydrosy acids which were not further attached* They
interpreted it by postulating that for reactions tTith
penaanganatc* the active oxidant was the free hydroxyl
radical or the 0'radical lon#
A survey of oxidations of organic corrpoundo by
alkaline solutions of potassiun nmnijanate as well as by
strongly alkaline solutions of potassiun hypooangnnatc
hae been reported by Pode and ""atcra ' • ?hey observes
that a slight reaction occurred with isobutyric and
isovaleric acids in 1QU potassium hydroxide* Inspired IS©
by the above studies Beelmith and Goodrich carried
out the detailed investigation of oxidation of various
branched chain carboyylic acids by (a) ItgHaO in dilute
alkali| (b) KHnO^ in concentrated alkali; (c) KgSg08 in
dilute Gllrali; (d) K2S2°8 in dilute acid, 2hey suggested
that the reaction proceeded via free hydroxyl radicals
according to the following scheme!
TnOj • OH ^ tlnOj • 'On
H R I , I
R - C - ( C H 2 ) n COgH +011 — ^ n - C - ( C H g ) n COgn • H20
H
n ' R
R - 0 ~ (CH 2 ) n COgH XL^. 3 . c - ( C H 2 ) Q C0j,H.
Oil
122
Persulphate was believed to provide hydroayl radicals
on thermal decomposition in tho follonin? nays
2-SgO0 ^ ^ 2S0J-
so£ • H2O ^ soj + ir* • ,OH
1?vide»c© for hydrosylation as tho ciejor effect
in the persulphate oxidation of organic compounds hae
also been reported by Bacon and Bott • 2hey found
that aqueous oolution of sodiun poroulphato containing
l i t t l e aoount of s i lve r n i t r a t e GO catalyst* converted
the branched chain fatty acids in to alcohols with loos
of carbon dioj&de. Pival lc acid gave tert-btitanol and
ioobutyric acld t a mixture of isopropanol and EGthyl
acetate in tho ra t io of 20tU The following mechanise
was proposed*
H C02H • SOJ ^ U COO'
R coo* — ^ a'* cog
R* + so30(&3^ — ^ .noWz • so4'
no s$g • ngo — ^ Bon • HaoJ
In the case of ioobutyric acid t tho «K-hydroecn atom
uao attacked followed by decarboxylation to propane.
A qual i ta t ive otudy or oridatlon of ioobutyric acid
123
132 end i t s ester has been reported by Fichter and Heer .
Oxidative degradation by chros&uEi t r ioxide in
acet ic a d d VOB developed as an effective nethod for
the location of a branch in higher oaturated carbon
chain aclde * # Detection of end products by cae chro
matography indicated that the expected cleavage products
were obtained froia the branched chain aclde* fhe oxida
tion of a ser ies of branched alkyl carboxylic acids by
Cr(Vl) oxide sms studied by Rocelc93 t?ho' determined the
retardation factor due to inductive effect of the carboxyl
group.
Besides permanganate, persulphate and chroaic
acid other oxidants have also been used* A sl ight
attack on loobutyric acid by vpnadlum in concentrated
sulphuric a d d has been reported 1 2 2 . The oxidation of
carboxylic acids by Co(III) was studied by Clifford and
Caters*6"* They showed that the ra te of oxidation of
isobutyric and pivel ic acids were of tho f i r s t order with
respect to the concentrations of the organic a d d and
inversely proportional to the concentration of the per
chloric a d d . Acetone ©eo detected to bo the oxidation
product of isobutyric acid while t-butanol was found in
the oxidation of p iv r l i c acid.
STUDIES mm ISOMfYKJC ACID
124
Order in Chronic acid
Sine oxidation r a t e nao neamired ae a function
of chronic acid concentration* In a l l the exoorioent©
the concentration of chronic acid oae kept so low in
comparison to those of substrate end sulphuric acid
concentrations tha t the l a t t e r renamed essent ial ly
conatant during any one nan» A s l ight increase in the
ra te constant wao observed tsfcen chromic acid concentra
tion was decreased* 3?he data are given in the tohloo.
FIG. 1 DEPENDENCE OF RATE CONSTANT ON CHROMIC ACID CONCENTRATION
2.0
1.6
o
en o +
•4-
0 10 20 30 40 50 60 70 80 90 100
TIME (mi'n) >
125
T a b l e - I .
Dependence of rat© constant on chronic ©old concentration
?< enp.o ?5 t • ! Cj ffetgSO^JPe 6.03j ^""iaotrotyrtc aci<3„/e 0.1D
^ " C h r o n i o ^ ecid
1ino(r;ino.)
0
10
80
30
40
SO
60
70
80
90
100
6B*66 Jt 10%
^ r ^ G ) 4*lo "cr 7
66.66
64.30
62.86
61.94
60.88
60.24
59.40
58.93
58.24
67.75
56.96
''.ate constant u m x
(tdnr 1)
1.803
1.803
1.798
1.791
1.784
1.779
1*774
1.770
1.765
1.761
1.755
10~3
33.33
104^rVf7ni>
33.33
31.70
30.78
29.65
29.02
28.60
28.31
28.03
27.46
26.90
26.20
2.00 as
X 10~%
4*l©^j5j
1.522
1.601
1.488
1.472
1.462
1*456
1.452
1.447
1.438
1*429
1.416
: 10*3
Ml*
Fig. 1. Curve 1 Curve 2
126
2 a b 1 e — XI.
Dependence of rot© eonotont on chroisie acia concentration-
tap.* 78 * , l°Ci£1lgS04 -7« S.OHi ^"Xaobtityrle e c i f i j ^ 0*112
acid 27.7? 3E lO^S 20.83 at 1Q~%
ftaelciins.) lO^Jf r^Cu) 4*Xoc£8rV5r i 0 4 ^ T r ^ ( n ) 4*lo&3frVi7
0
10
20
SO
40
SO
60
70
80
90
.00
27.77
26.85
26.10
25*64
25.18
24.7?
24.18
23.72
23.26
22.64
22.00
1*443
1.420
1*416
1.409
1.401
1.393
1.383
1*375
1*366
1.354
1.342
20.83
20.12
19*53
19.03
18.70
18.28
17.83
17.45
17.16
16.53
16.00
1,318
1.303
1.290
1.280
1.272
1.262
1.251
1.242
1.234
1.218
1*204
Sato constant
(rain. ) 2.1? x 10 -3 2.43 x 10*3
Fl*. 1, Curve 5. Curve 4*
127
f a b l e - H I *
Dependence of r a t e constant on chronic acid concentration.
tas>*« 75° t . l ^ i ^ f & g S O ^ * 4*0Ef /"Icobufcyrio acta,/** ®*m
£"C!iroialojr 18.51 x VCT^U 16.66 x lO^H sold
mmeCxalne.) I G ^ r ^ C n ) 44.1og£frV5r 1 0 4 ^ r ^ ( n ) Moeffr^J
0
10
so 30
40
50
60
70
80
90
100
10.51
17.77
17.37
16*66
16*30
16*04
15*70
15*33
15*00
14*45
14.32
1*267
1*249
1.239
1.221
1*812
1*205
1*196
1*185
1.176
1*160
1*155
16*66
16.94
15*51
15*18
14*70
14.33
13.97
13*38
13.24
12*94
12.52
1*281
1.202
1*190
1*101
1*167
1*156
1*145
1.133
1.122
1.112
1*097
Eat© constant 2.37 x 10 8.63 x 10" (Iain.*,,,*)
Fi&. 1* Carve 5* Carve 6*
128
Order in loobutygle acid
fo determine the ord^r t?ith reference to
ieobutyric acid, experinente oere performed with
different concentration© of the substra te keeping
the other factors constant* fhe order wee inferred
fron the plot of r a t e conetont YB* leotoutyxlc acid
concentration* She etrain&t l ine paeeing through
tho oricin indicated the f i r e t order dependence on
the eubotrate*
FIG. 2
EFFECT OF RATE CONSTANT ON ISOBUTYRIC ACID CONCE NTRATION
10 20 30 40 50 60 70 80 90 100
TIME ( m i n ) — *
129
2 a b 1 e * IV.
Dependence of ra te constant on the concentration of iaobntyric acid,
S?enp.» 70 £ *l°CfZ~H2S04-7"' 8,0H; C®*^Jm 33.33 X 10~%
^oobutyric.7 acid
4 . 0 X 10~2tf
floe(iaine.) l O ^ r ^ n ) 4*l©{ f*
0
10
SO
30
40
m w 70
60
90
100
Hate constant (nln.*1)
33 .33
31 .84
31 .45
31 .20
31*00
30 .81
30 .54
30 .30
29.97
29 .71
29 .45
0 .85 X
1*522
1*503
1.497
1.494
1.491
1.483
1.485
1*481
1*476
1.472
1.409
10~ 3
nj
5.0 £ lO"2!!
i&fftPjtTQ 4*lo<#/ |
33 .33
81 .27
30 .63
30 .24
29 .86
29 .73
29 .54
29 .00
28 .90
28 .64
28 .25
1*06 X
1.522
1.495
1.486
1.480
1.475
1.473
1*470
1.462
1.460
1.457
1.451
10* 3
Fl£> 2* Carve 1. Curve 2.
133
2 a U e ~ V*
Deponflenco »f r a t e constant on t h e concent r a t i on of i so lmty r l c ac id , *
Vmp.m 70 t *l°Cf £ % g 3 0 ^ 7 « 5.0Hf ^ f C r ^ * 33*33 * l O ^ n .
£"*eobt t tyr ic .7 **>•<> « 10~2n 25*0 s 10"2H acid
m*tmmmmmMmmmmmm*mmmmim**mmi*m i » — — — p » ^ » — i • »•»——««—«—»«pw—«»«p.ipu i n- i mmmmmm, m •i»iin«nii I
5H3©(cdno.) 10423fr^71tfl) 4*>lo&SrV5 r l O ^ r ^ n ) 4*lo^JTr^7
0 33,33 1.522 33.53 1*522
10 30.67 1,486 51*60 1*499
20 30.28 1.481 30.41 1*489
30 29.62 1,471 28*82 1.439
40 29*02 . 1.462 27.63 1.441
50 28*23 1.450 27,00 1,431
60 27.56 1*440 26*40 1*423
70 27.23 1.438 25.84 1.412
80 26.76 1,487 24.90 1.396
90 26.30 1.420 24*31 1.385
100 25*90 1.413 23.98 1.381
Hate conotant 2.07 x 10" 3 3.94 x 10"S
(Gin ." 1 )
Fin* 2* Curve 3 . Curve 4 .
131
f a b l e - ¥1 .
Dependence of ra te constant on tae concentration of ioobutyrie ado".
Temp*** TO £ . 1 % ^ g S O ^ J ^ 6.O0J CC^T e 3S*33 x 10"%.
^ l e o b t i t y r l c j ^ 8 0 »° * ^ ^ 75.0 x 10"2n aol<l
<WWM«Miiiwi«w»w^tMwwMiiwia«M>w^MWi^^ i iMKwumunman! mvmmmmmmmm**mmm**mmmmmmmmm*m*mm$mmmm*mim*mmmmmmm*m
SliaeCnino.) l O ^ r ^ n ) 4*los5Tjf1^7 104^Trv*7(n) ^ l o g ^ i ? ^
0
10
20
SO
40
50
O)
70
80
90
100
33*33
30.20
28,08
26.13
24.67
23.14
21.98
20.87
19*84
18.28
17.06
1*522
1*481
1*448
1.417
1*390
1*364
1*342
1*319
1.297
1.262
1.231
33*33
28.08
24.23
21.10
18.88
16*90
18.69
12.69
11*23
9.93
*•>
1.622
1*448
1*385
1.324
1*276
1.228
1.193
1.103
1*053
0.997
«•>
*?ate constant 6.60 x 10"3 12*15 x 10*S
(isln.""1) *N,MIIMMIMnMIIMMM*MH,MN^
n ^ . 2* Curve 5 . Curve 6.
FIRST ORDER DEPENDENCE OF RATE CONSTANT ON ISOBUTYRIC ACID CONCENTRATION
FIG. 3
160
160 -
140 -
120 -
100 -
< 60 -
• 60 -
40 -
20 -
0 10 20 30 40 50 60 70 80 90 100
1o'[ISOBUTYRIC ACID]
132
« a b l e - film
fie^caicnc© of ra to eoaotcnt on ffto coaceaatfetloa of icottwt^rio a d d .
uniiii 11 niiTiiiilii liniiiw
^Teotmtyric,,/ 100.0 x 1CT% a d d
«< 1 «BW*»l««»M«»M««««»i««»r»»«»«»«<>W»»«NlM»
«!©«$ (nlao.) i f l ^ C ^ J ^ H ) 4 • log C®*n*T immmmmm»mmmmm*m*0mtmmtm»mm*im
0
10
m m 40
60
60
70
80
00
100
33.33
20,60
21,24
113,61
13.03
11*06
0*03
7*£0
0,98
5,20
4*84
1*822
1.403
1*827
1*198
1*40
1.070
0.092
0.GS7
0.777
0*716
0,634
Re to conntant 15*84 • 10 (isln.- i)
Fi^* 2* Curve 7*
<-*
133
At high aoidltioe It is difficult to study the
influence of hydrogen, iono on the reaction velocity by
varying the pH of the aodlua* Nevertheless, hydrogen
ions as euch have been varied by varying the oulphurio
aoid content of the reaction mixture, fhe ionlo strength
was adjusted by sodium hydrogen sulphate* fhe rate
constantB at various oonceatrations of sulphuric acid
are registered below* She rate constant* obtained by
dividing paeu&o first order rate constants by corres*
ponding hydrogen ion concentration and by the square of
hydrogen ion concentration are shown in table IX* It ie
seen that the order of the reaotion is two with respoet
to hydrogen ions*
FIG.4 ACIDITY DEPENDENCE OF THE REACTION RATE
1-6
1.4
o
12 -
2 TO
08 -
0-6 0 15 30 45 60 75 90 105 120 135 150
TIME (min)—+
131
. a b l e * Vtllm &
Acidity dej>€»anaee of th© ©si&fstloa ^sto-
$eo tmtyr le sol^J^W Q»C!?£*Cr71J,'» 06,66 x lO*4!**
3*sa ^ l l g S O ^ 3*0&
£te<?C«&*i©*5 l O ^ C r ^ C T i ) 4*looflfr^Jr t O ^ W ^ ^lofsffK7^
0
18
30
45
60
78
90
100
120
138
ISO
2@*66
24*74
c*%S**»4s
22.20
21.00
20 . IS
19.13
18.46
17 .SO
17.10
16.68
1*485
1*399
1.365
1*346
l*B22
1*300
1.281
1.206
1.843
1*033
1*222
Z6*66
23*93
S2.2S
2US0
£0*84
19*13
18*17
17*18
18*50
18*70
14*93
1*423
1*380
1*347
1*326
1*300
i*esi
1.260
1.834
1.817
1.106
1.174
Beta conotant 3*18 x 10 k-3 3,7S 3E 10 i**3
K g . 4, Oarv© l . Curw £*
135
S a b l e - IX*
£lEQobtttyrlc meld . /* O,03| ^ C r ' 1 ^ 86.66 x 1 0 * %
£%230QJ 4.on 4.sn •«———i wi mi null ii iimmmmm**mK*0mm*miMmimmmmm*mmmmmt*mtmmm*mmmmimmmmi«II urn Hwmmmmmmm>*+mmmm*mmmmmmmmmm»mmmmmmmmm
f toeCalao.) l O ^ r ^ a ) 4 * l o c ^ r V 5 r I0*@9**7ln) 4 * l o c # r * 5 T
0 26.60 1,425 26.60 1.42$
10 22*88 1.349 81*88 1.342
W 20.60 1.S11 19.46 1.280
48 18.86 1.270 18.04 1.286
60 17.70 1.64? 16.28 1 .2U
78 18.58 1.21$ 18.80 1.182
90 lS.SO 1.193 14.83 1.1SS
105 IB. 12 1.179 13*08 1.116
120 13.83 1.142 11.80 1.071
133 12.90 1.110 11.00 1.043
ISO 12.10 1,032 10.18 1.008
Hat© constant 4.70 it 10*3 8.80 x 10*3
(lain. ) mtmmmummmim
Fl(!* 4 . Curve s . Curve 4.
13S
f a b l e - X.
Acidity 4©£©a5en<jo of tho oxidat ion r a t e .
s?e©p.» 75 - *i°c£^gS047 • £^eaao^Jm ©*®ni £"looUutyric ©old « O.gHf &r**fm 2S.m x 10* 40.
£^2S0fc? s.on s.3H
SteoCtaiiia.) i O ^ r ^ C n ) 4 * 1 O Q J P » ^ 7 l O ^ r ^ f l ) 4 + 1 0 ^ * ^ m n rm I M M I I M I H M « M N H M « | * N H M I »
0
13
30
43
60
70
90
105
tm tss ISO
26*66
21.46
19.20
17.00
16.80
14*30
13.33
11.97
11.00
9 .85
8*93
1*425
1.331
1*333
1.230
1*190
1*153
1,125
1.078
1.045
0*992
0.933
26,66
£0.63
17.70
15.63
13*63
18.64
11.3S
9.54
8.16
7.12
3.57
1.425
1.314
1*248
1.194
1*136
1.101
1.033
0*979
0 .911
0.8S2
0.746
Bat© conotaat (o±o. )
6.47 x 10 ~3 9*63 X 10 r 3
H o 4 . Carve 3 . Curve 6 .
13?
! e U e - I I .
Effect of acidity on the rate constant.
C#J C^J2 ** i f ^ x l 0 3 * xl04 (H) (sin."1) C&J C<T
3 .0
8 .8
4 . 0
4 . 5
5 .0
5 . 5
9 .00
12.25
16.00
SO. 25
25 .00
30 .25
s.ie 3.72
4 .70
5 .80
6 .47
9 . 6 5
1.06
1.07
1.17
1*28
1.29
1.75
3 .53
3 . 0 3
2 . 9 3
2 .86
2 .58
3.19
133
£fa© oxidetion of lootratyrte ctoid tmo sta&afi
ot e l s a i f feres t tenpemttiros wider ident ica l conditiono
of roeotento coaeositratioit© cn$ loa ie otroagtlu fiie
plot of log & VaHr- yielded a otraln&t 11a© sua the
an«rgy of aotlv&ttoit woo calculator firon t&o oloj>©» fho
value wao found to 14.? Heal. 5?ho other t&eraoaynooic
fmraootore i#o . A S + aaS AS^ ©ere calculates
fron t&c equation® given In Chapter I I asu3 tfte valueo
arc 14»0 Keel anfi ~37*8 eu« respectively*
FIG. 5
TEMPERATURE DEPENDENCE OF THE REACTION RATE
o
o
0 10 20 30 40 50 60 70 80 90 100
TIME (mm) >
139
2 a fc 1 © * ttli
*2€&&er&t®2® 5o|N2aSeaefc &£ ffso osi«3etioa rate
niim iinm iiiniK
5S8°& 343%
2ioo Csia**«) i O ^ r ^ C t ! ) a ^ i o & g f i ^ 1 0 ^ # i ^ C £ ) 4 ^ l 6 ^ r ^ 7
0
10
BO
SO
60
00
60
¥0
80
90
$0
26,06
W»f4
24.92
24.10
S3.18
22.20
SI* 64
81.03
£0.46
£0.06
19.60
1.425
1*410
1*396
1.382
1.SC5
**S4¥
1»33S
•W888
1*311
1*802
1.232
36*66
B§*?S
24*80
23*90
S3* S3
22.50
8 l t W
21.20
20.53
19.90
19.23
1.426
1*410
1.394
t»ffl&
U88T
1.S52
1.330
1.326
M n F *P<^0»*V#
1.299
1.284
Bat© conntent 2.32 * 10 (em**1)
>~3
Flc» C* 0BI*V© 1*
3*10 * 10' »S
Curre 2.
143
I t b l e * TUX*
2eas>e»etii~e acpenSimefc of tJso ©3!i3atIoa veto.
CbjpO+J* $.01i Ctmhnty&Q mX&Jm ©*8M| ffJ^m 26.66 x « f % «
fsEgmratare »»^I
Staioins,) t04 r 7(£!) ^loe^^f lO^i^n) 4aer#*f5r
MMtt»*<MM!W*lM«M««WW
0
10
so so 40
00
(3)
70
80
90
100
26.66
25.60
24.48
83* 6&
£2.78
CI. 65
180*74
19.90
10*03
lB .eO
17,18
i**i&
1.406
1*837
1*37$
usso 1.SS5
1*316
1*899
1*270
1.2G1
UC33
G6.CG
24.04
£3.28
22.16
JIG.07
19.G5
18*72
17*80
16.04
19.77
14*90
1.425
1*397
1.36G
1*345
1*881
1*897
1.S72
1.2SS
usee 1*107
1.173
Hate ©oiHsient
fir.* o*
4.00 x « T d
Curve 3 .
5.60 x 10*3
n tmmmmmmfitm^tmmmm
Curve 4*
FIG. 6
ACTIVATION ENERGY
o +
270 275 28.0
1 x 10
28-5 29.0
1 4 1
T a b l e w KIV
Tca^poarsture dopeadenca of tls© ©nidation r a t e .
^TigSO^JP* 5*0£f, ^ I s o b a t v r i o esX&Jm 0*20*
I I P . • — • i ni mi ii ii TI i . 1.1 mm i i mi i. m... iim. *v..mmmm,*„ «.,.tm~..m,. mm •in.i.ai. ,„..„., ...m.m^ II.IW.III
2esperattir« 338°& 363% «——«—•»••—-i ii III<IIM.IM>»M«IIIWII»III»I»M«P»«PW»IB^^ i » m m • I I » « ^ ^ » » « " " . ' W « W « ~ H » - « - « ~ » « » » » » I » « » I W
«iott (©ins*) 10*0*™?%®) M*t?£t^? l O ^ i r ^ C n ) 4*log^fj»^7 M^-MMMWWMtkMI
0
10
20
30
40
80
0)
70
30
90
100
26*66
24*77
22,77
21.10
19*60
13.33
17*28
16*10
14.35
13*36
12*20
1*425
1*394
1*33?
1*324
1.292
1.263
1*236
1*206
1*137
1.125
1*088
86*66
24*74
22.50
20*94
19*83
17.B1
15.80
14.40
12*63
10*70
9*66
1*425
1*393
1*352
1*321
1.284
1*343
1*193
1*158
1*101
1*029
0*984 —"•* *
Hat© constant 7.86 at 10~3 9*37 x 10~3
(cliu )
Fl«> 8* Carve 6* Carve 6*
142
$h© method of <»lctil*tl4n apifticft to otfaliiatfr
tho Ionic etraagth liao fee©a aescvlbeft «arlio** Studies
©itli ioobutyrlc aeid e&ot? e positive ©tat effoct* Bow* V
ever* t&o plot of yti ' 2 Vo-lo^ I£ So not give cay infogfio*
tlon ©boat t&c ffo©etiaii oecteilesw |fe© ta^lco fceJ©©
rcNSorfl t&o ©boenflatioa© at tmfiotio ionic otrc&£rth&*
FIG. 7
DEPENDENCE OF REACTION RATE ON IONIC STRENGTH
H
o
en o
+
0 15 30 45 60 75 90 105 120 135 150
TIME (min) *•
143
S a b l e - X?*
Ffjfcot of ionic strength on fch© rate constant.
te$* 76 1 .1°C O g B O ^ - 4«8S3f ^laefc&tyrte a e i a J V 0#8K§
ffx^m p-®*m * arts* imirl ilHwniirin HI >MiiiMiMjiMMw»«rwi«i»»i»«MiMM»»^^ »"" m i n i i i i
[baoxoj" mi o*m
//<«&<* 4*513 S#OH
ttao<Biiia«) lO^Jfr'jTlS) 4*loa^r^ l O ^ r ^ n ) MaGffJty
0
10
BO
45
60
78
00
105
ISO
133
180
2C.66
26.30
24*10
22*88
2C.18
21,48
SO*??
28.0?
19.49
18*90
10*40
i. ' iSS
1.403
1*883 '
1*38$
1*343
1*332
1.S1?
1*301
1*888
1*876
1.264
2@*S6
£5.58
23.03
SS*87
22*00
81*18
ao.co
19*S8
10.48
17.56
IS*?©
1.426
1*410
1*377
1,1550
1.342
1.326
1*303
1*280
1*255
1.245
1.C22 < — « — — ! — . — » > — — • M i n i HImnnniiiiii i .mni i»»W—MIII tmuM«mim\iMwmmi\MmmmK*mmm**mimmm0immmmmii I inmini
Rftte constant 2.86 x 10~3 3*00 s 1CT3
(«lii* } •mmmmmmmmmmmm i mmmmmmmnmmmmiutm—mmmm wirnimi »i IIIMI iiiiiniiini«i»«i<M»MW»»»M«»^-»««»M»»»Mi«»«MMiM«««
H^* 7* C«nr« 1* Curve 2*
144
? ft % 1 * - SSI*
2?ffeet o f iea io ©tsmsti i <m tSst© ret© eoaotast
*2mp» 7S & ml*Q /^gOg.TI:/o 4*$K| /TEeolHityrle ooJU^T* 0»8S|
wmmmmmmmHmmwmmim**mmmmmmmmmmmmm'*»m**m mummmmmmmmmmmmmmmmmmmmmmmmmmmmimuii WIHIHIIIHHIII'IHIIWIIIIJ — M
rbeei04l i*on I*$H M M W I J W W W W — » — « — — * • » — — M K » i ii inmii« minium ii minimi in mmm^tmummr*M0mmmummmim»mmm^mmmm>tmmmm*itiii u mi n w — w — »
mtxtsmth ,, , . —
Sine*aim!*) i O ^ r ^ E ) 4#l0£^rV5P S O ^ s ^ n ) 444©©^*^
0
10
30
m 60
70
00
165
120
135
150
80*66
25.G3
23*36
22*34
El , 20
20* 10
10.07
18*32
17*47
16*62
15*60
1*420
1*40?
JU308
1*349
1,326
1*303
i*sso 1*262
1*242
1*220
1*190
26* @6
24*86
23.35
22*05
20*90
19*44
18.30
16.00
10*64
14*68
13.63
1*425
1*303
1.3CB
uzm 1*320
1.283
1*262
1*227
1*190
1*166
1*131
Sat© ©distant $.38 % 1<T3 4*60 * 1ST (sl&« )
< — • ! — • — i n mill I ii n m i l — H I M H li milium i nun tmm*mmm0mmmmmmmi*mm*mu>m-mmtiiimmimlmimm
Fie*. 7* Curro 3* Curve 4*
145
? a fe 1 © - %VZl+
Sffe«t of ionic strength m the jrat« entoteat*
9«op. ?© * .1°S /fypQ^J* 4.510 £1t@etmt^flo ©ei&J*
©•sot S^7m %®»m * io"%.
fioOMU] , S.0tl M^MMfMHftHA*WMai«M|i
_Ionic 0«sn lifcreasth'
Tinefsinn.) 1 0 * ^ r * S t o ) 4 • leg £»vZ?
0
15
SO
40
GO
?8
00
100
13©
vm 150
2$*66
24.00
E3.32
§1*90
19«8T
17.38
16.00
15,62
14.IS
13.04
12.34
1*428
1.396
1.36?
1*340
1.387
l . £02
1*804
1.103
1*100
1.115
l . O t l
Rate constant S.S9 x IXt®
Hf|» 7* Curva S*
FIG. 8
EFFECT OF ACETIC ACID ON THE OXIDATION RATE
15 30 45 60 75 90 105 120 135 150
TIME (m in ) s-
(46
Xnfl*«Bee of ©©©tie ecitl cm tho ra to of oxidation*
Senp. ?& £ ** c ^ 2 s 0 4 - ^ « B»OH| £tm\mt#rlQ atfiajfa ®mm$
^$Wtie €UBlftJr W*- Of.10
Stce (idLtts*.) M^/JRp^fi) 4 * i © f ^ * ^ i O * ^ V ^ J t ^ 4 4 l o « f l & ^
0
IS
SO
45
60
7S
90
105
ISO
135
150
26 . GG
26.60
24 .43
23 .6?
£8*78
SI* 65
30*74
19.93
i9.or>
30*24
17.12
1.425
1.406
1*307
1*373
1.3G6
1.355
1.310
1.301
1*879
1.261
1.233
S6.6S
24.34
22.68
21.29
19*06
10*90
17*63
16.26
15.10
14.52
13*0?
1.426
1*386
1.333
1.3S7
1.300
1*27?
1.246
1*211
1*170
1*162
1*132
Rat© con0t«nt 4.00 s I0~S 4*98 x t0~ 3
(•la**1)
fie* 8* Curve 1* Curve 2*
147
£ © & % e - XJK* Influence of aeetlc ©em on tbe sat« of osdfiatioa*
*
ftgop. 78 t .1*0 ^ ^ S O ^ * 8#0f!f £^sobatyrto a©14jT** O.SiSf
<>IWWW«><»IPIIWPW»I«I»IWWII«>«IIWW«I»M»<WIW » ! • ! » < • < • > • — — B m a m a w i i i M n i n i I IH IM mi i IHIWIH an III mi inn in i L IHH I W « W — • I I I I unmiimin
^geati© ©oidjr 0mm o#©n
miaeCtai^*) lO 4 ^* * *?^} 4*l<jf^Fr*5r IO^JKP'JTIH) M®t0**^J
0
m 50
4S
GO
7©
30
103
150
135
169
26,66
84*03
22.14
20,50
19*03
10* 20
10* 68
1S.78
14.62
13*40
12.33
Hate constant 5.68 x
1*42©
1*380
1*348
1*312
1.280
1.260
1*837
1*198
utm 1.127
1*098
IQT3
26*66
S3*44
£1*80
20*34
18.34
I f .07
10.33
13.7S
12.38
10*86
9*90
6*90 x
1.480
1.370
1.338
1.308
1.2G3
1.S3S
1.105
1.138
1*093
1.036
0.995
ICT8
(Bin*""*)
Hg. 8. Curve 3# Curvo 4.
148
f e fc % # - XX*
Influence of acrfelc acid on tho r a t e of oxidation.
Seap, 75 1 *1*0 ^ g S O ^ J 1 * * 0*0t!f ^ l e o t m t y r l c aeiaJ'W 0*2%
£8x?%F» m*m * to*4!?. IHMMIIWIIMIWIIIII ir mini iw iummrw m niiinnicniiiiijiiiiiin m i i i i m — m m m i 1 m nwjiinmiiiinianiiwuiniwiiiiiwiii nun 11 »• « w w — — *
g e n t l e a c t a , / 0.TE 1*00 <wn«*mwnii M W — > — » » > • — w — w — M X — I 1 »n i i i i l i i m i i i i i u i i M i y — n m m n n iiniMwMiMwiliiiwWMWKwiWMWWiMt w^
StosCisias.) »4^Tr'S^n) 4^io^r1f5r i 0 4 ^ r ^ o ) 4*Io^& mwmniiiira—M«—«—«•n»'»« .n—wwwi«p—•»' <MK- in mnniniiiiiiii 11 MI pi m**»m~mmmM*n.i ,Mmmm**-m**»ma**mmm •inn 1 1 nun
0
m
m
SO
GO
70
80
00
100
r*r> a*
2£*78
SO* 30
10*14
16,82
15. S3
10*73
11*44
10*10
6*08
1.425
1*3S7
1*509
1,258
1*££0
i * i a §
1*137
1*097
1*008
1*007
0*994
20*06
21.64
19*23
17*30
10.97
14. 2C
IE* 60
11.00
9*03
8*44
0*90
1*420
1.335
1*284
1*2S9
1*203
1*104
1*108
1*041
0,992
0*926
0*030
Eat« constant 7.00 s ! 0 ~ 3 0.04 * 10~3
(st la* ) constant 7.00 * t£T® 0*04 * 10~3
Curve 0* Carre 6*
STITPIBS WITH X3GVM,£RIC ACID
143
In ox&ot to aotrtcalno tue ©rdor of reaction
vitti reference to osdflemt* osoorinenta txore perforacfi
varying tlJ© concmtmtioa of ohrooio e©!3 at eoaoteat
tsolmtyric eisd oulphurio ooi£ ooiietsatrotioaa. Sio
plot of log /jSr\y y°- **DO *le*<*o<* &o©a otsalcbt lineo
IJI a l l the oaseo* SSio *oto constants *?or© aotozoSziod
fro© tho elopes of tbooo liscso GBS war© round to oo
olcoot eoaotent tn&lcpMng f irot or&er dsspcutleaeo oa
osltoot concentration. She ret© det© arc otiom feolous
FIG. 9 DEPENDENCE OF RATE CONSTANT ON CHROMIC ACID CONCENTRATION
• i 1 " J '
0 10 20 30 40 50 60 70 80 90 100
TIME (min) *
159
Bepeftde&ce at reto oonotant oa chroclc ©old concentration.
flSarauLoJ' 60.6© x HOf a 33.33 % IST^U ocid
aMfeoae.) 10^*^(0} 4+xo i?^7 to4^jp^n) Mo^p*1*? v* tiMmm*0*mmmm
0
10
20
30
40
§0
€0
70
80
00
100
66*66
63*12
€0*5t
g7.se 63.95
SO.OO
44.90
4**83
S?#14
32*62
' 23*00
. 1*083
jueoo
1.7S0
1.757
1.73S
1.098
1*008
i.ois 1.S00
1*013
1.461
33*33
31.74
30.SS
£9*10
27.S6
M*f?8
20*10
£3*83
£g*lS
!?0.46
18*00
1*022
1*801
1.480
1*403
1*440
1.410
1*300
1*377
1.340
1.311
1.870
Hate constant 6,00 x 10~3 6.40 x 10~3
<©ia* )
f l O 9. Ctirve 1* Curve 2*
151
f s % 1 e «• 1X31* m
B<r>«3s£ence of ra te coneton t on dbro©le oel4 cojntesifctiratlCKw
23.8© x ICT4!! acid
18*01 x 10*
SiceCsslJie*} 104^P^7(!3> 4 * l » c $ ^ f ^ 4 # 3 P ^ » > 4#l0Qj3fr^f
0
10
20
30
40
m m 70
80
90
100
£3,80
S3. 26
S2.03
21.2S
SO. 46
19.43
18,86
17.14
15.60
14.83
13.77
1.S76
1.SG6
1.34S
1*326
1.310
1.23G
1*860
1.234
1.193
1.173
1.130
18*01
17*07
16.07
16.10
14.77
13,60
12.06
11.33
10*30
0.10
7.96
1.2G7
1*254
1*827
1.806
1.169
1*183
1.000
1.054
1*003
0*000
0 .901
l a t e conotant tnXnrh
6.40 X 10 r*3 7.82 x 10 r »
SI 3* »• On*ve 5. Cfttnr© 4 .
152
~~Vepm®mm of f l t l constant on &M®Me aei& eo&«$efIfration.
2«§jsp* 75 * *1°0$ ^gSO^J^* 5.01-j ^Iso-iraXeiele &A*Jw 0.1B.
^hrcele so la , / 16.66 JE KT4!! 15.33 * 10*%
ttneCalas.) lO^r^TCn) 4*l0$£?rirf7 i O ^ P ^ H ) 4*Xo@^Sr,?j7
0
10
so 30
40
m CO
70
80
m 100
Hftt«
16*66
16*18
16*40
14*74
13.84
12*90
11.63
11.02
10*00

3*20
constant 7*56 x
UG21
1*200
1*188
1*169
1*141
1*111
1*06®
%mOm
1*000
0*960
0*914
10~3
13.33
12*40
11*06
11.22
10*60
P.83
0*16
8*47
7*74
7.10
6.67
7*36 x
1*124
1*003
1*074
1*050
1.021
0.098
0*062
0.929
0*889
0*0©1
0*817
10*S
( iRlfl . )
Tir.m 0* Curve 5* Car*© 6*
153
She ardor uitii reelect to ioovelerio aeia tsao
flotomSJioS ©xaetl# t a tb© ©ase tssy a© I» tfeo oadflotioflT
of ioobutyrlc moid e»<3 tmm& t o be uni ty , fiao plot
Of t a t e constant ?© iooimlex4o oeiS concentration i s
ottowo l a the ficuro i t encl tfe© fiato oro given In the
follotaiiift tobies*
FIG. 10
DEPENDENCE OF RATE CONSTANT ON ISOVALERIC ACID CONCENTRATION
0 15 30 45 60 75 90 105 120 135 150
TIME ( m i n ) *-
151
T a b l e • XXI?*
Bepeadence of rat© ocmetemt on the concentration of i sovaler ic aeld*
&*$. 73 £ •1°C| /TfegSO^J^. ©.0ETf fft^Jm 33*33 x 10-%*
^WW>aWWBW|wtWW>i»^lWWiWi>i^ WWII waW^«|P»*|M*|Wl»
^ D m l t r l e ^ 4.0 x 10*% 3*0 s MT% no id
nan i i i i M i « — w w w m i n i«imtmmmmmmim»mmm-\\m\tntm« i i mmm*mm*m*iam*m'i&mmmmmmmMaBmmmmMmmmmmmmmmmmmmmmim»mimm»
EIDOCBIIIS*) afiiJ^JXn) 4*ioQ£jTrv5r I O 4 ^ 1 ^ ^ ) 4*ioa^KplSf
0 33.33 1*0-28
18 33*06 1*819
30 32*30 1,515
46 32.34 1.809
<30 31*88 1.803
73 31*30 1*498
00 31*03 1*401
105 30*30 1*404
12© 30.04 1.477
133 £0*33 1*460
130 28.60 1+436
Rate coasfcant 1.08 x 1(T3 1.64 s 10~3
(nln* ) ' " • " " '"•" """"•» "' "»iim HI m m mn inn iimn nnnniim mi «i » i n •IHHIIIIILIIIIIH i
11^* 10. Carr© 1» Curve £•
33*33
33*06
32. 3G
31.70
30*08
30*40
29,60
C9.15
28.37
27*60
00.87
1.522
1*319
1*600
1*001
1*491
1*403
1*471
1*464
1.452
1*440
1.420
155
l i a b l e «*• iv$m
Dependenoe of rate constant oa the eoaaeatmtiets af ieovaleilo aald*
Jeep. TO * .1°0$ ^f&gSO^** O.OH* $*®ty** 33.33 it ttT%
£lQ«yfElertcjr 10.0 % 10*% £0.0 * 10*% acid
<——«»—««»•———<«.'«w«^wn i i iiin nnniinmiiiii i i in'ii limine m i MI in iniium m i innii luainnninnwn u n m . i nuium m m — —
MMJF1*»»\ A^~mJflT +*Amjnti**\ A^.mM* nmtMtm*) m*$fc¥i7(t# 4^©affr^7 tsrSv^zTim 4«**«^vj7 M M W M H M
0
10
30
40
00
f 8
00
103
120
133
150
33.33
38.13
si.ss £9.36
20.37
£?•£?
£6*12
24.40
23*34
01*70
19.64
1»S£2
1.30?
1.49S
1.470
1.43S
1*434
1.41?
1.387
1-3CS
1*336
1.203
33.33
31.00
ca.50
26.98
25.40
23*10
20.83
10.17
17.8S
18.67
14.08
1.322
1*401
1*434
1.431
1.404
1*363
1.310
1«£S2
x«%m
1.103
1.140
Bate constant S.fO x 10"® 5.44 s 10~3
(nin* )
Ftfj* 10. Carve 3 . Curve 4.
FIRST ORDER DEPENDENCE OF RATE CONSTANT ON ISOVALERIC ACID CONCENTRATION
FIG. 11
x
0 5 10 15 20 25 30 35 A0
10* [ISOVALERIC ACID 1 „
158
T a b l e • X3TB1. Z>epenrt<mce of sa te coaataaf oa ttt© concentration of isovaler ic nci«J-
2«np» 73 * *1°C| ^ r ^ O ^ J ^ ©.0t!| jgr^T* 33*33 at 1©~%.
£\mm&9*lQj 2S*0 * 10"*% 33*33 x 10*% eci<3
! ®<cdii0*> lO^f^CE) 4*lo^?r^7 iO^ff^fS) Mogff*^
0
IS
30
43
€0
73
90
103
ISO
133
130
33*33
30*93
£8*8?
26*07
24*14
£8*83
80*22
17.43
13*63
14*03
12*44
1.622
1*490
t#460
1*426
1*388
1*348
1*303
1.241
1*104
1.147
1*034
33*33
30*34
23*10
23*70
22,13
19*33
17*22
14*30
IE* 26
10* 87
8.87
1»522
1.405
1*4£8
1*410
1*343
1*201
1*230
1*133
1*008
1*011
0.948
Bate constant 7*73 x %£T® 10*30 x 10*' Com**1)
MN*MI«ftrtlWWMM*MrtWttfM*W*^^
Piflm 10* Ctxrvci 5* Carve 6*
157
_Jforlttftlfflft-Og gate neaataat «&fh &2k$i.tw
UulptmrlG ael& TOO *a*ie& f*o® 9»0£! t® 59*
K*o ret© «a0 fotmti to laweBtse with luereeeliic wt3>-
pfearlcr eel* omtmt of fcfc# jpe&otim sHattare* Bime
enlphnxie e©i<$ 1© ceaoiaereA t© dleeoeiete into E&OJ
lorni only, ^aima hl©tslph©$© wan es«*5 to eot^eaeste
for the @&e«ig« of ionic etrenatli* She results of
aeidltjr variation arc reported in the tables feoloi?*
FIG. 12 ACIDITY DEPENDENCE OF THE OXIDATION RATE
>
? 10 +
0 15 30 45 60 75 90 105 120 135 150 TIME ( m m ) — -
158
s « * i • - m i t • JtajUftty dependence ef the oxldatloft wit®.
feci** 75 * •l*Cf £%2m4 * SIIBSO^JF* 6*>0tt| £Tt©wtiI.@*l©
&<*&,/« o#«Ri ffr^m m«m x a r t s . •i»n»iiin.lii.i«iii.um n
^ ^ ° 4 - 7 S*0CE 3*5Q
[MiMwtiM iwMwiiiiiiiiw'iiininiMnriiiiim
^B#C»I»&») .u^^S^a) ^to^?i?^r t o ^ ^ ^ t t ) ^^AeS^iT mmmmmmmmm***mm
G
11
30
48
•0
75
90
105
%m 44Xft
150
26.60
m*w m*4e 24..03
23*74
9P^7ll
21,23
20,10
10*30
SB. 57
17#0#
1*425
1*419
1*40®
1*391
t*370
1*30$
&#t§H7
1#305
1»S85
S#S64
t»23S
2G,66
So.SO
m*m 23.50
2^*00
20.30
10.05
17,40
15*53
14*18
S&»43
1*4©S
1*411.
t»383
1*871
1*342
i»w 1»S77
1.240
1*191
1*151
1*094
Bat# ooacteat 3*3f * 10** 4*SE at iflT® (ssla**1)
i ilnr w o w — , inn—«——•—»—Mi n nm——mm i mil in mi i run nun i ——w—n iiuiKin in wm~mm—mmmmm
fig* 18* Curve 1# Qunm 2,
159
t A b i © ** zmzt* Acidity dependence of the oxidation rote.
ta^* 78 £ «iact jfligso * nmm^Jm 0*0111 £lo©*&ie£io
Sid®CHi»©*) io4^Pr^7tn) z+tac^T^ w4$x^in) 4*i0^^J7
0
10
so 45
GO
78
90
105
im
133
ISO
Kfcfce Jonatant
80*60
25.45
24.34
23,23
SI* 64
19*84
17.S7
15,60
14*40
18*12
10*42
6*14 X
1.425
1*405
1*330
1*366
i » H 9
1*207
1.244
1*19$
1*158
1*083
1*018
10**^
26.66
24.20
225* 80
21.64
10*80
17*03
I S . 15
13* 10
11,20
3*43
7*8©
8*37 x
1*420
1.3G3
1*37©
1*335
1.296
1*243
1*100
1*117
1*040
0*974
0*803
Uf* (•to.**)
ft** 12* &irr# 3* Curve 4*
163
l e b l e -* XXIX,
Acidity flopcndencc of tho oxidation rote*
tteldJ'W o*2Hf £&*%?** E0.66 c SO*4!!.
£V°4-7 MB
0
IS
so 46
00
7S
90
ion 120
1S6
180
2G.G6
24*8?
2S.43
10*70
17*80
13*94
11*40
10*27
7.47
5.38
4.10
1*48&
1*390
1*390
1*204
1*335
1*144
1,056
1,011
0*87$
0*731
0*621
Eat* constant 10*80 * 10*5
(fain."1) mmmmmmmmmKmmtmmmmimmmmmmmmmmmmitmmmmmmmmmmmmmmmmmmmimim
fig* 12* Ounre a*
161
T a b l e - XIX.
Effect of a c i d i t y on the r a t e cons t an t s .
(i.w.pfc*»u*,.; d S . ^ i e - S d n . - l )
3.0 9.00 3,37 1.12 3,74
3*5 12.25 4.82 1.37 3.93
4.0 16.00 6.14 1.53 3.83
4.S 20.25 8.37 1.86 4 .13
5.0 25.00 10.28 2.05 4 .01
162
UmGttm mm otndleft ut a&x QLtXvrmt $@q*5©r«*~
tmrm aa&es lAontleal #caoti$» ceafiSf iono. Aetlv&tifla
eaer^ and other thcnsodtytiaislo f> &*ois®ter** <w©rc calcula
ted fccn etandar6 ©$sa%ioi5 tiescri&aa audio** 2lie
vr.luoo £<mad ores
Aetiv&Uoa oaorisr • 11*8" Ktml
Scat of ao$lv&ti«n « 10»Q' Kc«/
I^tfop^ of activation m ««46*© «a*
tfie rat© constants aft veriomo toopevictareo are riurea in tb® f&Uotiliig tables.
FIG. 13
TEMPERATURE DEPENDENCE OF THE OXIDATION RATE
0 10 20 30 40 50 60 70 80 90 100
TIME (min) *
163
a b l e * 1XXX»
2c£peratar© - dependence of the xmatttm rato*
£?v^?m 26.66 at 30"%. • i '"'in t — — — i n n ii — M W I I ninnm i u — i — » - I I I i i inn i i . i nmminiwiifjmiMn i i iiinminim i n i mi i
ScE^orstur© 243% 243%
fteeCt3lnj3.) I0 4^r*^(?3) t+Uagtr^ i 0 4 # r ^ 7 ( H > 4«0©r#**37 M*MM4«l«MIMpNMNM*fmMMIi|MMM
0
10
80
SO
40
50
60
70
80
90
too
25,66
25 .63
28*04
24.50
23*74
£3*04
22 ,88
21*87
£0.87
19.84
17.98
1*423
1*40S
1 * 3 8
1*?389
1*370
1*362
1*340
1*354
1*319
U297
1*234
26 .60
26*03
25 .28
24*40
22 .80
21*90
20*70
19*63
18 .43
17*33
i « . ie
1*425
1*413
1*402
1.387
1*337
1*340
1*316
1*293
1*263
1*236
1*207
Hato constant 3.32 x IXF^ 4*70 x 10~S
(ciln.*1) • • •MHMMI IMlMnMMHMMi l^^
fir* 13* Curv© 1. Carve 2*
161
S a l t s * X1XX2*
3?«33peratttre dependence pt the oxidation rate*
^fr 'Sr • 28*66 x lO^t!* • • M M » » « K » . | i . M » M - < . . . » M - » > < » « « » « l « » » » « » » « » | » « « ' » " » ' i i ' i » l l « i » 111 I lull II IIIIMI « — — » » I i»lllllimilllHI|i|l|li'[ II mm i III JIIIIIIJUIIIIIIIIHH II .1111 Ml lllllll
Secpenitttr© 3530£ $S8°E mm tin ii iw——' iM in i i i i i i i i i ii niiiii ii inn i iim. 11111111 ii m i«»«n«iin WI IW—nmmi mm u i »i«nw.mm r m — m — i •"'"' » n » »
SteoCclnfi.) I04^r^7(l3) ^ l o ^ T r ^ lO^f l f r^n ) 4*lo|i^?i??f7
0
30
SO
30
40
SO
60
70
80
90
100
36.63
m»?o 23,98
23.12
21.8V
19*96
19.23
18.03
17*14
16.14
15.54
1.426
1*410
1.880
1.364
1.340
1.300
1.284
1*2§0
1*254
1.203
U186
26*68
25,58
23.87
22*S0
20*41
18*70
17*30
15.04
15.13
14.32
12.76
1*425
1*408
1.578
1.SS2
1.510
1.272
1.238
1.200
1.180
1*156
1*106
Hate conotent 8.82 x HP* 7.88 x 10~3
El 3. 13* Oarv© 3* Carre 4*
FIG. 14
ACTIVATION ENERGY
165
f a b l e - X X m i .
Sooperataro dependence of the reaction rate*
^llgSO^JT * 3*0nf ^ I s o v a l e r i c a c i d . / • O.iTt
Seoperator© 363% 368%
SJioeietfta*) l O ^ ^ n ) 4 a o ^ r ^ 7 l O ^ r ^ T I n ) 4 * l o ^ ^
0
10
so so 40
m m 70
80
90
100
Kate
26.66
24*26
22.13
20.51
19.88
10.74
I S . 13
13.98
12.20
11.27
10.30
constant 11*50
1*426
1*385
1*340
1.318
1.276
1.S84
1*180
1.146
1.006
1*052
1.013
X 10~3
£6*66
83.70
20.90
17.98
10.40
13.07
11.06
10*33
9*03
*
•
16.13 x
1*483
1.375
1.320
1*263
1.190
1*136
1*063
1*013
0*936
•
«•.
10*3
( tain.*1)
Fi8* 13* Curra S* Onmra 6*
166
"By vetoing the concentration of oodiun E>GE»-
efaloriit©, t&e ionic etrezs^li of ttie rcaoUea Mature
TOO r©stt!at©a« A positive influence io oboorvod* £he
plot of Qjb 2 tfG.los*. folio to eiiro any eosolstsivo
rosulto» £&© rate co&ataftfco at vortou© ionio otreagths
OP© rosi©tc*eS tmlot?*
FIG. 15
DEPENDENCE OF RATE CONSTANT ON IONIC STRENGTH
0 15 30 45 60 75 90 105 120 135 150 TIME (mm) *
16?
f a b l e • XOTV.
i3ff«ct of i on i c ©treastifc tm t&fc *>sd,a&tio*i r©t©#
2enp*?&£*l°Cf ^TKgSO^JTw 4.5!"f £" i novel ©ric aciajfi* 0#l!1f
^??f7 » 2e*ee x 10*%
#acio4-7 i l l o*®n
. Icasle^ 4*63 S*Ofl
SineCdno*) 10*&rt*7(n) A+XO^T1^ I 0 4 ^ r ^ 0 ) 4* lc#35r 9 j 7
0 26.66 1*480
IS 26,20 1*418
m 86*46 1*408
40 24*67 1,392
W 23.83 1*3??
78 22.00 1*360
90 22*16 1*34?
108 21.S3 1,333
120 20*70 1.31S
133 19*67 1*294
150 10*96 1*278
26*66
26*34
25.50
24*33
23*17
22.02
20,90
19*64
18*66
17*73
16*73
1*420
1*420
1*406
1*336
1*366
1*342
1*320
2*293
1*271
1*248
1*223
Hate oonatant 2.S0 x 10*^ 3*7? x iO" s
{©In*""1)
Up* 15 . Curve 1* Curve 2*
168
2 a © 1 © - XXX?*
Effect of ionic strength on the oaslfefelon rate*
teg?.7S£a0Ci £ \ S 0 4 - 7 * 4»S1!| ^ I s o v a l e r i c ool4j r« ©•US
O a C l O ^
l o u l c o t rencth
Tino{nina.)
0
IS
30
49
60
73
90
105
ISO
135
ISO
1*01!
3*5H
Dal*/p*lf*7tn) 4+ ioe^f 1 ^
26.fi 6
26*35
24.46
22*03
21*33
10* 65
16.00
16*90
15*80
14*64
13,38
Bate constant 5*56 x (»ln*~*)
1*423
1*404
1*388 -
1*360
1*330
1*293
l*g8§
1*SS7
1*158
1.163
1*136
I O - S
1*611
6.0!:
l O ^ r ^ H }
26*66
26.50
24.20
22.84
£0*63
10*83
17*16
13*60
13*44
11*83
10*23
7.:
.
83 X
[
|
Mjogffiv.
1*423
1*406
1*38-3
1*338
1*310
l .£84
1*334
1*193
1.128
1*073
1*010
10"*S
Ti»m 16* Carve 3* Carve 4*
169
T a b l e - XXTO,
VtSeot of ioa ic strength on tfco ojsi^&tioa rote*
HIM ii IIHI HI I I mi , i « II i >i IIIIII wmi mini im iiH.ir 111 urn, in. urn IIDII i n n i n, i i n»»i iimtm iin.iiim
if&acio^ zjm
^ tome . 6*SCt otrenijtfe
tiB©(ffilii0#) l O ^ r ^ C l t ) ^ l o c ^ P * ^ ft*wnwfi.> nmmmm***wmMM*wwmm\«\m<irmmm*mmmmmm
0
15
SO
43
GO
75
00
100
120
135
150
26. GG
£4*30
S3»20
81,13
Iff. 26
17,20
15.20
13,08
11*06
8,90
6,80
1,4S5
1,394
1*365
1,384
1.204
1,238
1*181
1.116
1,034
0.9S0
0,332
• 3 Bate constant 8,43 x 10
« — — « — mi ' mmmmmmm ui i nniniii — x — m m
H£> 15, Curve 0«
FIG. 16 EFFECT OF ACETIC ACID ON THE OXIDATION RATE
0 15 30 45 60 75 90 105 120 135 150
TIME (mm) *
170
? a U e * OTflTIX*
Inflnenee of aootio cold on tho o 2d Motion sate*
fesf>*rs£.i®C§ £ " ^ 0 ^ . 8*OH$ £ ls0va le«4c a<61Gjf« 0*XSf
iinnimimnlimnii i i - . » m » m ip» IWI.IIM u i. H 11 iiiir i nun I mi ilim, nnm n ••••mmuiiiMiiiiii
/"iifsetic 7 0.1M 0,20 acid
s?io«(si«s*) l 0 4 ^ e ^ i > 4 * 1 0 3 $ * ^ l O ^ r ^ n ) ^U^tt^/ .MiiiUBiimiimiiliiii i
0
is so 4S
€0
?0
90
108
ISO
135
ISO
26.66
£5.07
£3.34
81.1?
19.S7
17.16
14*0$
13.14
11.60
10.03
8*34
1.425
1*899
i .SS8
1.32G
umt 1.B34
1.178
1.118
1.0C5
1.003
0.021
26. €6
24.00
88.70
20.06
10*00
16*M
14.52
12.67
11.08
3.08
7.12
1*423
1*394
1.SS8
1.3SS
US7B
1.229
1.162
1.102
1.044
0.958
0*053
Ret© constant B+22 x I©*21 0*94 x 10~3
l i" . 16. Ouinr© 1. Curve 2.
171
? & fe 1 e * XKXSZtl*
Influence of acetic a©16 <m the oxidation rct#*
W i l l i ii HiHiHMUDMiim—WW—Winn I milium I I • I ill unmi i i n u l n w c — w — in mil nil urn
SioaCcHita*) l O 4 ^ ^ * ! ) ^ l o ^ r 1 ^ 0
15
m m m 9B
00
105
180
136
150
26*66
2C.85
20*S3
10.36
10*90
14.02
IS* 10
9*94
7»8&
8*34
4*50
1.425
1.359
1*312
1.S63
1.202
1*146
1*003
0*90?
0*00S
0*802
0*699
B»tc ceaatsat 10*40 x 10* (ada.*1)
I I n r -f • II i in II I I in I I i m i II
Ttr* 16* Carve 3*
172
T a U o *» XXXIX.
Influence of acet ic aei& os tfe© oxidation «**©•
2©£ij**76£»l0Cf ^ffegSO^T* S,OU| ^T^eofBleifio aeia.,7* 0*1H|
£*Ac©tio JT o*7ti i*ot! acid
<«»>MIII | I» .»W>|MWMW»»<WMMM»M«MWIM««»»«« » » » I II IIIIIMn II11 Win fill 1X111 III HI' rim IHIHWIM H M H I I I I II 11 III H HHlHIHIlllllljlMllll II Wlllll I I I . W — M M ! 1 I H I HU IH illl IUHI III II M l IHIHIII
$iee{ffiisa*) wftffx^Jim A+toggSe^ 10 4 $T*^!3 ) Mo^*^ tmmmmmmimm
0
10
20
30
40
SO
SO
70
SO
90
100
26*60
83*07
21.10
19.50
17.90
16*37
14*37
IS* 38
12. £5
11.00
9.S?
1*428
1*372
1#.$S4
l*g0O
1*234
1.S19
1*17£
1*1110
1*033
1*044
0*981
28*60
22#1B
19.70
18.GO
10*16
14.82
12.00
11.32
10.80
9*04
7*10
1*43
1*346
1*090
1*269
1.CO0
1*171
1*107
1*05?
1*003
0*931
0*801
Hate ooa9t«mt 11.18 x ICT3 12.17 x 10*3
( s in .* 1 ) < — « — « — w » ~ « — i i i HI nnummmmmmmmmummm i — — w i — i w i i m m i x — » w i ml n iniim niinni
Fie* 16* CaTV© 4* Carro 6 .
Kinetico of Oxidation ot phenylaootia aoid
173
The oxidation of phenylated fatty acids is
icportant fron the biological Poin* °* view since it
throws light upon the mode of oxidation of fatty acids
of related structures in the anlsal body, ^al:in134,135
studied the oxidation of phenylated fatty &ci&& in vivo
and la vitro by hydrogen peroxide. Hio results afforded
the moot convincing evidence of the occurrence of 3 -oxi
dation in both the cases showing a clooe analogy between
then. The use of copper as a catalyst in the oxidation
of phenyl derivatives of aliphatic acids has been reported 136
by Jones snd Tactean » They observed that the ©roe of
oxidation was increased with the increase in the side
chain. The special susceptibility of phenylacetie acid
to oxidation was ascribed to the feet that -oxidation
took place at the nuclear carbon aton to which the side
chain was attached.
Bacterial oxidation of benzoic and phenylccotic 1S7
acids by Vibrio nee reported to take place by different
cctabolic routes, but a section of tr icarboxylic cycle
uhich enters through -ke toc lu tar ic acid van sho\3n to be
cotxon to both.nocfeenhull138 demonstrated that the
i n i t i a l oxidation of phenylacetic acid by "en ic i l l iun
174
chryaogemra took p lace i n the s ide chain GO dehydroftena-
t lon process with the formation of benealdehyde* Phenyl-
aeeialdehyde and hydro35yph<*nylacetic acid were envisaged
03 in te rmed ia tes . Hercurlc end lodoccotate ions were 139
observed to i n h i b i t the ox ida t ion . Spiro suf&ested
tha t «K -ox ida t ion of f a t t y ac ids i n the organism traa
not due to a pecu l ia r ox ida t ion neehanlsn, but i t was
H a l t e d by the proper t leo of the oxi<?vblc conpound which
detercjlncd the pecu l i a r p o s i t i o n of a t t a c k .
The oxidation of phenylated f a t t y acid® by hot
a l k a l i n e permanganate ?m& i nves t iga t ed by PrEhevalsfcli
t?ho reported t h r t the oxida t ion took place a t the carbon
atora next to phenyl group. ?he hydroxyl proup eras i n t r o
duced which v/ae then fu r the r oxidised to a carbonyl
conpound and f i na l ly t o benaoic ac id . The remainder oide
chain was oxidized to carbon dioxide or to a d ibas ic a c i d .
Oxidative degradation of carboxyl lc ac ids by potassium 141 permanganate has a l so been reported by Skraup e t e l .
?heae workera obtained bensoic acid fron phenylacet ic ac id ;
benzoic and bcncoylfornic acid frora hydro cinnanic and
phenylbutyric acids by ox id i s ing then n i t h one t;ole of
acid and 0 . 1 co le of po tass lun permanganate i n presence
of two equivalents of potassium carbonate . Penaaneannte
oxidat ion of phenylacet ic and ohenylpronionie ac ids in
175
acid, basic and neutral media rcas carried out by Diiaitrov 142
and Stefanova • Formation of pyruvic acid, a© ident i f ied
by cas chromatography, ras at t r ibuted to the breaking of
bensene rin*;, Use of solid manganese dioxide as an
oxidant for the oxidation of organic compounds rrae reported
by Bl-Sadar rcho obtained benzaldehyde (50;S yield) and
carbon dioxide fron phenylacetlc acid*
The usual oxidative degradation process in l l#a in
chemistry to vani l l in by nitrobenzene was applied to modol
.145
144 compounds . I t ras ohown that phenylacetlc acid was
oxldlEod to bencoylfonsic a d d . Peroulphate oxidation
of phenylacetlc acid gave diphenylnethane (362 yield)
and boncaldehyde. Bacon and Hanna used argentic plcol inate
a© a sui table oxidant for organic cocpoundo in aqueous
suspensions* ?hey found that phenylacetlc acid rcao
oxidised to benEaldohyde by th i s reagent. r a t e r s 1 2 3
obtained l i t t l e benzaldehyde fron the oxidation of phenyl-147
acetic acid by cobaltic sa l t s* Fieser ' s oboervationo
on the olkyl side chain by chromic anhydride strongly
s u r e s t that the degradation of an acid oide chain proceeds
by en in i t i a l /? -oxidation followed by decarboxylation to
/3-keto acid, 2he lower honalo/fous acids a r i se by the
s i n i l a r processes* Hence they concluded that the phenomena
ofR-oxidation was not liiuitcd to biological oxidations.
176
only* The echenatic repreocntation 1© ea follows*
-(CiI2)gC02H ^ -(CH2)7C0CH200^H ^ 3 *
.(CHg)?CO CT3 > - ( C H 2 ) M COgH.
148
Hecently ox ida t ive decarboxylation of phenyl-
a c e t i c acid has been ehonn to proceed through ion ic
meehenieo and not via freo r ad ica l one* Beajsoylforcie
acid has been pos tu la ted ae t he key i n t e m e d i e t e , the
formation of which has been i l l u s t r a t e d by e i t h e r r a d i c a l
or i o n i c Bcchaniscu The r eac t ion has been shotm schema t i c -
a l l y a&t Co,0 I x ^ °
Co /
t <W!12 CfrCBB - | " °
0
0 0 H O I II I II
I I •A Co Co
CgHg CH2 COgll 0
°o \ " ^ r -i * c o o (A) _ L ^ Cfy - J H ^ C X £ - > [j6n5 - c - cogiij ^
CgHgCno fcrvl S
C.H.CH.
177
CgHg - CH - C 4? 0
0^0 "^ I
c^cagCOgH
Ctf% - <? " ? C6H5 I I pOJH
. 0 C - CH - C-GL <? \ / \ 6 5 0 0 OH
A C e H 5 - C . C - C6H5
X C
0 * 0 CHCgEg
(II)
i ^ 6H 5ci i 2co 2n
C-H- - C • CO. 0 (1)
C6H5 C - CO
CH
C6H5CH2C0gH
SC€P5 C A * ?° " ? * °6n5
o^ o' o
In the present chapter studios on the oxidation
of phenylacetic and boncoic ocido isere conducted in order
to net an insight into the mechanise of oxidation of fatty
acido by chronic acid*
178
Stie dlaeppeatfaae® of cforosio acta fgllaweti
apparently f i r s t <OT> Mitotic® Tstion i t VBM esatsiaefi
a© ploto Qt leg ffi^J ?s.tiC0« She typical p lot 1©
a&otm i a figair© i* I t lo to bo noted that acextt&se
in ohrdoi<* acid i e ac«o£p&ai©fi by increrse in ro te
conotrnte. fh& oboervatioa© a t v&riouo ehrooie acid
c©ae©ntrGti«ms arc tabled bulow*
FIG. 1 DEPENDENCE OF RATE CONSTANT ON CHROMIC ACID CONCENTRATION
0 10 20 30 40 50 60 70 80 90 100
TIME ( m i n ) — »
179
'i a b 1 © — X.
DepenAeaee ©£ rate constant oa dirosi© &<sid coficcatrctioii.
2cr:|>.?^i0Ci CbgiQiJm S.OZ!* £"rhenyl acetic cs&aj?»6. 6x10-%, M*iNMIMMMMri|WMMnMMM
^Tb&roslo./ m9m at lO*"^ 33.33 x HOT4!! aclff ___ N H M M t e l M M i M W M
sioeCotao.) i o W ^ n ) Mte&fy i o 4 # r ^ n ) ^\*%£$*nJ wmm^mmmmmimmmtmm
0
10
a) 30
40
60 •
60
70
80
90
100
66*66
05.13
63.72
62.53
60.40
67.73
C5.05
ss.sc 60.52
48.40
46.26
1*823
1.814
1.004
1.7S6
1.731
1*701
1.740
1.710
1.703
t«€84
1.665
S3 . S3
$2.00
30.97
29,72
28 . m
27.23
26.S2
24.90
2 3 . 64
23.34
21*80
1.022
1.B0S
1.401
1.473
1.436
1.4S8
1.423
1.397
1.371
1.368
1.333
Bute coasitsnt 4.20 x 10*3 4.27 * 10*3
(©la .* 1 ) «M»»M»»««««M«»W>^MI»Ml<l»lH>il<w< . |»«ll<ll. l ll«»w^ r mi | II nun | n i | i i i , mm>——mmmmmmm
HLp:. 1* Carre 1. Cunro 2.
4
188
? ft % 1 6 -> I I .
Se^eaflence of vote e«m®ts&t ©a crisfwd© acl<§ coaoeiitiratiea. fJc^p.yoi#l^Ci C^J^4f7m B#on|£>henyl aoet ie aciaJPWj. 6x10"%. a mum n II.II ii ii»»MiM»iit««>iw»i«i>w«wi»Mi«»»*i«»^^ ii urn n
^Chrosaiejr S3.00 a 10*4 1S.31 % J0**a m in i n i T O N mmiMniiiii——iw—« mn M I M I — I I U IIIII.IHIIIIIII.IBII i II mi urn i m i nuiimiini iiininn i i i n m w — i i w w u i n i m i iiiin n
24BeCrai»».) i C f * ^ * 1 * ^ ) 4#lo$J!r i^7 l O ^ t f r ^ C n ) M&e&ePj w>mnm wm\mmm*\Mwmmmm*mm*fimm*mmmmmimmm**m*im
0
10
20
30
40
80
m w 30
90
100
S3.80
&S.6©
21.0?
01.20
so.se m*m 18*80
10.18
1T.SS
16.68
15.53
U&B
1.S88
1.339
1.300
1.512
1*308
1*874
1.280
i*S39
1*£8S
1.191
18.51
1?.?0
16.75
16.10
15.83
14.03
14.00
1 3 . SO
12.60
13.03
1 1 . 32
%mzm
1.240
1.S24
1*200
1.198
1.160
1.146
1.123
1*100
1.080
1*084
a te cottsfciilit 4.14 at 10"3 4.60 at 10* (saia.*1)
H?,» %• Curve 3* Otinw 4 .
181
i s b 1 e - I I I *
itepoBdeito* of nit© «cm©tcnt oa efesonle ac id oonceafcr&tion*
£"fcfer0Bl0„7 *$*$$ * K*"4** 1S*33 x 10"4H
TlmCoiaa. ) 10 4 #r ? f7Cn) 4 + l o ^ P r ^ 7 M^&FtjXn) 4 # l o ^ r V ^ 7
13.33 1.124
12*8© 1*009
11*90 1.07S
11*40 1*050
10*70 1*033
10*33 1*014
9*74 0*038
0*122 0*060
8*63 0*933
8*14 0*910
7.60 0.880
4*86 * 10~3
Flc* 1 . Curve 5* Curve 6*
0
10
m m 40
so 60
70
80
90
100
Eat© constant (rain."*1)
16*66
1S*87
15.10
14*44
13*70
13*83
1£*70
12*03
11*36
10* 66
10*03
1*221
1*800
1.178
1*180
1*13S
1#1<31
1*103
1*030
1*008
1*088
1.001
4*75 % 10~3
182
T a b l e » £7.
B©ge»4@i3e© <*f mt« oonutast <m eftreiaia a©14 c&XMSfcftirotioa.
fGhtoBlejr 11. to a 1©~% acid
ttUatMaB.) 104#rVf7(n> ^ l o g g ! * ^
0
10
so
30
40
60
$0
70
80
90
100
11.10
10.63
10* 88
0.S0
0.50
9.OS
0.07
©•OS
7.SS
7.00
6,55
L045
1*028
1.012
0*994
0.977
0.DS6
0.93S
0.905
0.070
0.043
0.816
Sat a constant 4.73 x JflT* (airu )
Fig. 3U Curve 7 .
183
$He oxidation of phcaylacotie acid h$ eturenic
a e i i was* otudied a t lo© oabstrat© eoneemtratioii an*
could »ot feo varied raiek booaaeo of i t s poor oolubi*
l i t y . Hotrovefp f i r s t order dependence oa euootrato
tj©s estimator faros the plot of ra te conoteatt feu oheayX-
ncotic moid coneoRtitotioa* A otrs ight l ino passing
thrott(jh the origin CEO oet&itiocK* the r«t* a t vnrioue
concent re t lone of pbcrvylccotie ooid aro gives i a the
following tabl®s«
F7G.2
DEPENDENCE OF RATE CONSTANT ON PHENYL ACETIC ACID CONCENTRATION'
o
C7>
o
0 10 20 30 40 50 60 70 80 90 100 110 120
TIME ( min ) *
184
? ft * 1 4 - 7 .
Xtopeatfeaoe of r a t€ coaotcixt a» t&e eo»e«*ntrati0n of pticnyl&oefctc ac id .
£st5rp.7o£.ldC| £ \ « % 7 * ^OCf ffr^Jn 33.33 x 10*%,
©old
*itte(nlna»> J j O ^ r ^ H ) 4 + 1 0 ^ * ^ i O 4 ^ * 1 ^ ^ Mntsff**l7
0 33.35 L&gS
IS 31*88 1.603
30 30.93 1,490
48 30.10 1.470
60 29.4? 1*470
75 S8.S3 1.485
00 27.77 1.443
105 27.08 1.432
ISO fi6.ge 1.419
135 85.66 1*407
150 24.87 1.39©
Hat© constant 1.96 x 10*3 2.5S x 10~3
(sin.-1)
33.33
32.20
30.06
89.00
£8.97
28.16
26.98
26.20
25.25
24.SO
£3.60
1.522
i .007
1.489
1.476
1*402
1.450
1.430
1.418
1.408
1.390
1.372
Pifc. 8 . Curve 1 . Curve £ .
185
2 a k 1 © • Vtm
S@$«gidUino<i of rat© constant on tin* concentration of pheiiylooetic add*
^cap^aS^c* ZligS04w7» a*oni £$**}?* ss.ss * io~%.
&cl4 •«MMIW«illW»l««MI|Wt«»MI«»««i«W»MI<WII««l>»^^ HI Hill I H"l»»l«
flneCtalR©*) l O ^ r ^ C D } ^ l o ^ J f r ^
0
m m m 60
?s
00
ios 120
12SS
150
33.33
S i . 6g
30.1?
S8.?2
2?*08
£5*44
S3. 08
63.10
28*10
CI, 14
20.13
1.582
1.S00
1.496
1.458
1.43S
1.405
1*380
1.363
1*344
1.325
1*301
Bat© constant 3.7? x 10""3
(ai iu )
Fig. S. Curve 3 .
1 S t>
? a "b 3t e * ¥lt#
Dependence of rat© constant <m the concentration of phcaylncetic sets*
£ecp.?0£.loCi 0*2^4,7* S»OH| $***?* 33.35 s 10*%,
£>heayla<i«*ilc,/ 8.0 x 10~% 10*0 * 10"% oci4
I I W W I M I I I I I M limn urn mi mir mmm mi mi imiirii n inini mil mi min i in i i nun n» niiinii mi <i H Mi—iim ... liiiinni.nniii
SteeCoin©** if l fyPr^n) A4toc£p**lj' l O ^ r ^ O ) 4*1Q^^7 • W K U H M a W M M
0
10
20
30
40
m GO
70
60
00
100
33.33
32.24
30.90
29.70
28. ©7
gf.es
26.44
£8.23
23 . 9B
22.62
21.54
1*882
1*608
1.490
1*472
1.4B7
1.440
. 1.422
1.408
1*380
1.354
1.333
33.33
SI .80
30.46
20.06
27.83
23.07
24.33
23.32
22.03
20.70
19.43
US2£
1*303
1.433
1.463
1*441
1.412
1.390
1.367
1.343
1.316
1.388
?ate constant 4.28 at 10~3 5.72 % 10*3
r i g . 2 . Curve 4 . Curve 5 .
FIRST ORDER DEPENDENCE -OF RATE CONSTANT ON PHENYLACETIC ACfD CONCENTRATION
FIG. 3
f
70 -
60 -
50 •
40 •
30 -
20 -
10 •
0 -0 1 2 3 4 5 6 7 8 9 10
10 [PHENYLACETIC ACID]—-
187
So suitable buffor oould be prepared for study
ing the Influence of pH on the react Ion rate* never
theless, hydrogen ion concentration was obanced as
ouch toy varying the aulphurio aoid - soditift bisulnhnte
ratio in the reaction mixture. The concentration of
hydrogen ions waa calculated on the nseunption that
the first dissociation of oulphurio aoid is complete
and second dissociation io negligible. The effoet of
various concentration* of oulphurio acid on the rate
oonatants are given in the tablet. It io observed
that the quotients obtained by dividing paeudo first
order rate constant* by hydrogen ion concentration
vary but by the equare of hydrogen ion oonoentration
reaain oonetant in each run* Xt indioataa that the
reaction is of ssoond order with reapeot to hydrogen
ions*
FIG. 4
ACIDITY DEPENDENCE OF THE REACTION RATE
15 30 45 60 75 90 105 120 135 150
TIME (mm) >•
188
2 a tJ 1 © * Til l*
a d a i t y &ep«siSeRe# of the oxidation rattj*
^v^/» m*m x IQ"4^. II mi iriiiiiinw«»M»«»i»ii<>»iw<»«wi<ia»iiw««iM«iw>w««»wwi^^ HI immmmmmmtm*
gtyzo^ 4*on 4.sn
Stxae(BUuu} M^&iFjfiU) Z+tQ^J**? 1 0 4 # r ^ 7 { n ) ^ i e c ^ P r ^
0
IS
go
45
€0
70
90
100
120
135
150
Eat© constant
16. GG
1S.70
10.12
14*48
13*04
13*05
1S*$S
turn 11*13
10. 5 G
10. 20
9*33
1.221
1*197
1*1S©
1*160
1*135
1*118
1*003
1.071
1*046
1.023
1*012
X 1 0 - 3
16.66
13*40
14.70
13.95
13.08
12. SS
12.10
11*36
10.70
0*03
9*34
5.77
i#m 1*109
1*167
1*144
1*116
1.093
1*033
1*050
1.024
0*997
0*970
X 1CT3
dain."1}
Fig. 4* Curv* 1* Curve 2*
183
? g b I 9 •* XX*
Aclfllty dependence of tit© astfisilen rate*
2eiS|>»70£»loei £^g80 4JT # ^-brflSO^JT « S*0E|
£>&ciyrlae©tic ae3.qjr» 6 ^ 1 10*%!,
/ l i g s o ^ 5*on s.en
2toodsinB,> mAff^7tm) A^ucffJ1*/ tofifft^tty Moeff**1!?
0
i s
m m 60
7S
90
108
120
135
is©
Kate
If* 86
IS , 30
14*54
13.6?
IB*83
11.88
10*93
10.43
9*88
8.80
7.97
cons tan t 4.82 %
1«2£1
1*104
1*162
1*136
1*008
1*063
1.038
1.018
0.981
0*944
0*901
10~3
16.66
18*40
14*13
12*87
11*50
10*82
9.78
8*30
7.87
7.10
6.17
6*47
1.221
1*187
1*180
1*109
1*060
1*022
0.987
0*944
0*896
0*851
0.790
X 1 0 - 3
(«ln.-*) MMHMW««W*IMM«NI*MM»»ltnMM*fWn^
Hfr* 4 . Curv» 3* Carve 4 .
ileiaity depes^efioe sf the aaa&tioa ra te .
7eop*foi.i°C| £":!sso4-7 • £*teso4jr « 8*OH$
S^7 * *<*•** * 10-%*
2ine(islss.) lO^r^Cn) 4*io^r^7
0
10
w 43
30
78
eo 309
120
13S
150
Rate
10*01
Hi. 10
13. 3B
11.^7
10,40
#»16
7*8?
7.00
ۥ0)
8*S0
4* £4
1*221
1.180
1*126
1.067
1*017
0*001
0*006
0*840
0.702
0*724
0*6E7
coa&tent 8*05 x 10~S
(«*R* )
Hr* 4* Sanr© S*
191
t a b l e - XI.
Effect of acidity on tbo r a t e constnnt.
£X J OZf * * 10? Jk x l 0 3 J L . » io4
(K) (Bin.*1) £ll!7 ^ ! 7 E
Hii'ili • • • • • • • • • • • M P — — — I • r imin i im—»»—Minn II mil H u m — — » — » » ~ » « — ~ — » — — • — • • —
4.0 16.00 3.33 0.83 2.08
4.5 20.25 3.97 0.88 1.98
5.0 28.00 4.82 0.96 1.92
5.5 30.25 6.47 1.17 2.13
6.0 36.00 8.05 U34 2.23
192
£<s?spegattiiro aenmd<moo
?&e effect of tes^oratare- on tho ojEidotioa
rate tree doterdnea xm&or oitailor reaction conditions.
Activation energy* heat of motivation and entro©!* of
activation were determined fros the forouia© esentienea
©Xresfiy. Cboervations reoerdG*! trader identical OOBM-
tio&o eat varying tenporatara m,r® prooeatoa in tfa©
follesln^ tabic©. Sao vnlttca of activation poronotera «A*:
— Baoresr of estivation » i?»9* Eeol
aent of motivation » S7«£i K<ra^
Smtropy of activation » -£8#S ©n#
FIG. 5 TEMPERATURE DEPENDENCE OF THE REACTION RATE
0 10 20 30 40 50 60 70 80 90 100
TIME(min) >-
193
r a h x « ~ X I I *
$@sp©ratur* d*tpettd«»ae of t&e ositoUoa rate*
£"%8°4.7» ®*<>®t £>he»ylisee%ic ©eiaJP « S.3 * l ( f %
feeperetstr© 33B°K. 343%
<S$&®{ siiis.) i O ^ r ^ a ) 4*lo^r^7 lO^r^H) 4*l0g$r*37
0
10
£0
SO
40
SO
60
70
80
90
100
20*06
26 .35
26.10
23*90
28*34
24*8?
24 .40
84*05
23.65
23,30
22.98
1*426
1*480
1*410
1*413
1.405
1*593
1*38?
1.3S1
1.373
1*367
1*361
06.66
26 .15
86*34
24*73
23 .76
23 .30
28*00
22*40
21*83
21 .38
20 .72
1.426
1.41?
1*404
1.303
1*376
1*367
1*360
1*330
1.340
1.330
1*316
Rate c o n t e n t 1.53 x 10"*3 S.43 x 10~3
(lain**1)
£l£* 6* Curve 1* Curve 2.
!94
T a b l e ~ XIII,
2ai9«v»tere Aeptntfane* »£ is® oisi&atioa rate.
£"^2S04-7* 8*OI3f 0 6 W l f c « & t i c s^^-T" • 5 * 3 * 10~%f ^5Tr^7 • £6*66 x 10*%.
« « I I M » I » « » I I « » » « I W » I W — « i — w w » I « I IIII IIIIIIIIIm»mi»wa»««<«—»pwi—MW<«»X»WII [iii 111 nil I I — I I — m m — i n n i n mmmmmmimmmmtimtm
fenp*»ratai?« 343*% 353%
mMfsitte*) i o 4 ^ ^ ( n ) 4*io^pp7f7 io4^r^fCn) 4*10^^7
0
10
20
3D
40
50
00
70
80
00
100
26.60
83*08
25*43
24 .0?
2S*7S
£3*80
2S.50
81 ,60
20.84
£0 ,05
19.20
1*423
t . 4 1 4
1.405
1*392
1.375
1*363
1.3C2
1*332
1*319
1*302
1*283
P6.66
25.r>6
2 4 . G2
23 .32
£1 .00
80*80
19* 23
18*16
imo I S . 20
13*30
1*4S8
1.407
1*391
1*367
1*340
1*313
1*284
1.259
1.S33
1*211
1*184
H&t© constant 3*33 x 1CTS 6.33 x 10":
(am**1)
Fir* 6* Ctarr« 3* Curr© 4*
FIG. 6 ACTIVATION ENERGY
O
28-5 4 29-0 J_ x 1 0 — > T
30-0
195
T a b l e »?«
?ecpttr«tti£« &«#ea&e&€Mi ©J* t&e 6sl4at&oii rate.
^ee^eretttre SS9% S05% mmmummn. < in in nu » » •
Sftsw(Gtno.) 10 4^r^7(H5 4*looflfipVSr S04^r*jj7tn) 4*l©$JyV j7 PMMiWWWWW^Iiii^MiiiWllliiiilllWI'WiaM mmm*mmm+i0*mmmmm*mim{im y nui%mmimmim*immmm*i*fmi mi*m+mmmmmmmmammmimi****
©
to so so 40
60
m 70
80
90
100
S6.G6
S*S.S3 '
24,00
ES.70
21.10
19.S7
17.82
16.44
15.32
14*07
12*90
1.4SS
1.407
1.533
1.35G
1*334
1.001
l . g S l
1.S15
1.185
1*148
1.1*0
86.60
S i . 14
S3.©?
si . en 10.70
10.15
ie.10 14.37
ir.»35
12.00
10.66
1.425
1*400
1.374
1.336
1.294
1.253
1.206
1.1S7
1.125
1.08H
1.023
$fe*« constant 7.7$ x 10 ,-3 0.53 * 10*S
Kt£. 6* Curve 5. Carve 6.
196
..%ff«ot of ionic atrgnpth,
f&e iaa&e nfcriBigtti of tfa« reactimi eistur©
fca» feeraa controlled by &$&it*£ wnrttrao sasounto of oo&it*©
pere&ier&ta* X<mio otroa&th of ih© facrtfiws fees bcea
calculated on the fol low in.-; eeeunptlono.
(«t) Sfe© f i r s t dioooci ration of oulpburic mold i©
complete aa$ eeeond <Sio®oaioti««i lo nogliftioio*
(b) Plienylncetlc ®«i$ &&£ chronic acid ao not eon t r i
bute <ii$ni£tetgatti|f to the t o t a l Ionic otrc^stli*
S?ts© data appear in ti*e foiloi&as tabXest
FIG. 7 DEPENDENCE OF OXIDATION RATE ON IONIC STRENGTH
0 15 30 45 60 B6 96 196 106 126 1S6
T IME(m in )—>
191
T a 1* 1 e - X¥*
Effect ©f i sn ic utre>b *>s the react ion r a t e .
c^*V5^.10C| ^IfgSO^J^* 4*6C| £>&e*iyla0eiic a o i $ J « 8.3ja0~20 t
£~N*c*°$ Oil 0.80
Ionio 4»S S.O
ii i i imr ifi•>wim ura iw nin irn-iiTrirwrnmnninnfiifirWTriiriii rir^miiiwn-rrrriw -rrt IT—^r—r-rrirrT lirrfmifrTrrffTrr—"T '— '—?-T\—"*—'-trt —p^^.——p^.^^—irr nr1l,wlllM
StoeCrata©.} I O ^ S B P ^ C ) MQ^T*^? l O ^ r ^ K ) &+l<*€ffr^7 mmmm**im
0
IS
30
45
60
75
90
106
120
13S
150
16.66
16,80
15.88
10.40
14«@£!
14*46
14.04
13.76
13.33
12.94
12.80
i*m 1.209
U19U
1.18?
1*173
1.160
1.147
1.137
1.128
1.113
1,096
16.66
I S . S3
13.80
If}. 83
18*08
11.76
10,82
10.23
9.90
9.60
9.£3
1.881
1.182
1.140
1.110
1.082
1.070
1.033
1.010
0*996
0.982
0.966
% t e constant 2.03 * 10~5 3.90 x 10~S
(Bin.**)
f ig . 7 . Curve 1* Carv* 2 .
198
Sff«et of ionio strength on tiio renctioa rata*
2asp.7S±.l°e| ffg^+J* 4*SH| £>fe<sayliioetl© a c i a j ^ 0.3x10"%}
£ ^ © 0 1 0 ^ 1.03 1.5H
. i t t l i c S.SG 6.0H s'tttm&tS:
l#iMattMMf**MftiiMaMto|«|ii |^
Slaefoiiuu) 1 0 4 ^ J 7 < 0 > 4*l©c#rV][7 1 0 4 ^ r ^ < 0 ) ^ l o ^ r ^
0
IS
30
4$
60
78
90
106
120
135
150
13 .63
14 .38
13*3©
133*30
11,42
10.85
10 .03
9 . 2 4
8 .74
8 .08
7 .50
1 .221
1*163
1 .120
1*090
1.050
1.038
1 .001
0 ,965
0*941
0 .907
0 .874
X6.QG
ie.27
13.00
11.92
10.84
10.29
9.34
8.40
7.97
7.22
6.70
1,221
1.1S4
1*114
1.076
1.038
1.012
0.979
0.924
0.901
0.838
0*826
Hate constant 5.48 x 10*3 6.S2 x 10~3
(nln.""1) mtmmtmmmmmmm^mmmmmmmmmmmmtmmn i 11 •mm »u iimini i hmmmmmmmmmmmmmmmmmmmmmmmmmmmmtmtmmmmmmmmimmammmm
Tit.* ?* Carre 3* Oarv© 4 .
$ { * % ! • - ZVXX»
£yrf««t of ionic ©trcngtii ©a the reaction, r a t e .
fe©p*702*l°Cf £?&%&\J' * 4*SH$
£">iie!iyle©etic mt&JF a 6 « 3 x 10"*%f
^ ^ * 16*66 x 10~%» T . -• -[- M~^^1^J_^_^.^„„_,^J—,T^... r . •—n.j: i.r.:-..::.iv..-._:r."r ' "i rrn-~-~~— —-,
C*®®®*®&I £.00
10iile_ 6#5H
Sioeinlns*} i O ^ r ^ r i ) 4*16^**^7
0
m 30
46
60
7©
90
105
10)
13©
160
16*66
13.90
11.34
10.48
9»44
8.50
7*98
6*86
6.08
8.7S
4*90
1.221
1*143
1*064
1*020
0*078
0*930
0.902
0.836
0.784
0.758
0.690
Rat© constant 8.86 at 10~3
(Bin.*1) — • • • » ! • u n i i i ifiimii .11111.11111 ii in in.i
Flf. 7 . Curve 5 .
FIG. 8 EFFECT OF ACETIC ACID ON THE RATE CONSTANT
0 10 20 30 40 50 60 70
TIME (mm) »
80 90 100
N» \/ V
T a b l e • IVIIX.
Influence of a c e t i c acid «© the reac t ion ro te*
?etsp.?s£. 1 % Z ^ g S O ^ w 6 .0^ |£>hesyr leoe t io adiaJ'W 8.3xlO"2E|
^ f r 1 ^ * 26*06 x l O ^ E .
« — « W M M 1 M I I » t — l l i r » l il»lll« in» inn IWillHI » II •M»IM>«ll««»MM»»lia»»»MIII««l|«l«»«»il^
acid
5?iDu(stno.} I Q ^ r ^ n ) 4 ^ o ^ P r ^ T i O ^ r ^ n ) 4*l0g^Tjp^7
0 86.66 1*42® 26*86 1*425
IS £4.90 1*396 24.08 1.39?
30 S3.G3 1*362 £8*06 1.361
48 21.66 1.335 21.46 1.331
60 20.23 1.306 19.05 1.300
78 l t . 1 3 1*S81 18.72 1.272
90 17*42 1*241 17*66 1.247
105 16. m 1*214 16.43 1,218
IS) 14*78 . 1.1*0 16.05 1.177
135 14.07 1*148 13.80 1.140
150 12.73 1*104 18.18 LOSS « T » I mi ii c i i i — o n — p i n in mi iimmtm*mimtnl],\H*-iiiimmt*mimmmmmmm0'i'mmm>*mi\ mi m — — i i i niim mum
Rate constant 5.20 x 10*s 5.44 a 10~&
(lain* )
Hr. 8. Curve 1. Qarve 2.
S a b I » •» 2IX*
Influence of noetlo ncid on tfe* rectction r a t e .
tes»*752#l°Ci ^ g S O ^ * S*01|
^fAeeiioj^ acid
?iDo(ninc.)
0
as 30
46
SO
75
90
105
120
135
150
ID
Bate constant (a l i i .* 1 )
o*sn
l^r^Ttn) 4*leQj3f*^7
26*66
84*57
22* gg
eo»ig
17.00
16*50
15*0g
13*33
IS* 37
10*96
9.62
6*90 x
1.425
1*300
1.347
1*304
1*2^3
1*817
1*176
1.124
1*03£
1*039
0*988
10*3
H g , 8. Curve 3*
202
2 a b X « - XX.
Inf luence of a c e t i c &®14 or, the r e a c t i o n r&ts^
2eEj»*78£.l0C| ^ f l l ^ S O ^ - 9#Oni£>heQylaeetii5 sc iaJT* &.3xl0~%It
ffr^/m S0.06 x 1Q~%*
• w w w w — — i — i i i i n iniiniinmiii ii—KI mini mil i » mm.nuimi i m mmnmm MIIHIII I»I I I I»IH.I ' I I»<W»T i n lyiiiuiiiiniiii I I H — » — — »
^"Aoetic.7 o«m i»on
ecid
SimeC»in».) l O ^ J S r ^ r i ) 4 * l o $ J p r ^ 7 10 4^**l7Cn) &+l*gffl*?i7 mmm^m^mmM^mt^i^iMt^mMmmmmfi^^tmt^
0
10
20
30
40
80
CO
m 60
90
loo
Vbktm conotant ( j a i tu* 1 )
26*66
25*38
22*12
20,25
18.00
10*08
16«SO
16*86
14 .64
13* 3a
ii.es
7,
1.425 36*06 1*426
1*368 g3*S4 1*371
1*344 20.32 1*300
1*306 IS.26 1.261
1.276 rr.m i*240
1.237 16*04 1.205
1.225 14.48 1*161
1.200 13.00 1*110
1.103 11*?? 1.070
1.1ES 10.70 1.030
1*078 0*30 0*060
7 .73 x K T S 9*20 x i 0 * 3
t i g . 8* Curve 4* Curve 5*
C H A P T E R V
Discussion
203
The kinetic© of oxidation of lo^er fat ty acids
by chrocic acid clooely resembles that of ftydrocarbono
by the sane oxidant, the trend in reac t iv i ty of the
nothyl f methylene end methine groups has been found to
be similar in both the react ions . Uhc introduction of
phenyl j*roup has the seme effect ao in the case of hydro
carbons. Proia the e i o i l s r i t y in the retea of oxidation
of hydrocarbons and fafcty acldo, concluaion i e drawn
that the reaction possesoeo inportant features of carboniun
ions.
Fron the prcl iainary expezinents i t i c obocrved
that acet ic nnd pivpJLie acids are not attacked by carorrio
acid# I t indicates that nei ther nethyl fxoup nor oarboxyl
#roup io oxidised by th i s ozldant. $ho reoiot iv i ty of
these groups towards chromic acid oxidation hao also boon
denonetrated by liiakinbottom and Rocek • This clearly
Indicates that methylene and tscthine groupo of th© a l ipha t ic
acids are oxidised.
?ho reaction ra te depend© upon the f i r s t porer of
Cr(VI) t the f irot power of substrates* but the dependence
of ra te constant on hydrogen ion concentration i s of
204
second order . I t i s oeen t h a t as the concentrat ion of
Cr<VI) i s decreased, tho f i r o t order r a t e constant
inerwaaes. But tho i n c r e a s e i a not to an extent such
tha t o h i ^ e r order t e r n i n Cr(Vl) racy bo defined.
S i n i l a r e f fec t wao observed by riovicfc and ^eotheiner*^
i n tho oxidat ion of loopropyl alcohol and by Itcop and
xratera i n the oxidat ion of formic acid and formalde
hyde* Tho explanation put forward by Uestheirser t ha t i t
i a due t o the hydrolysis of the dlchroant© ion
Cr g O| • HgO ^ as 2 ttCrW£
seens to bo the cor rec t one.
Rocek and Krupielra choked t h a t i n s t rong
sulphur ic acid solut ionot the r a t e of chronic acid oxida
t i o n of iaopropyl a lcohol follows H t a lnce the rcator
noleculc doea not p a r t i c i p a t e in tho t r e n o i t i o n o t a t o . 41
^eatheiraer showed that W 0 1© not the correct acidity
function to be used in describing the protonation of the
acid chromate ion and tho EL function ohould be used.
fhe latter increases nore rapidly tsith decreasing v/ater
concentration in the solvent than does E olnce both o
proton and acid chromatc ion r i l l be hydroted choreas
the n e u t r a l product c h r o d e ac id w i l l have a conoiderable 1*50
degree of hydration. £oe end Stewart introduced a new
205
function II- «• loft ^gO/^HA and showed that it gave a
ouch better fit to the lonlsation data than th© simple
acidity functions H 0 or II-. By cooparinf the values of
theoe functions, it is eeen that the value of new function
decreases nor® ropidly than !!••• "The values of these
functions at higher texaperaturee ere not reported in
the literature but it heo been determined that a very
snail but systematic drift ie found in the relationship
betneen acidity function and ricid concentration nith
changing temperature. Howevert the plots of logarithm
of rate conetante againot new acidity function yielded
a straight line but tho olopo nao quite high* The high
slope nay be due to the use of unvalid acidity functions*
It has been ohotm that the oxidation of organic
subotratcs by Cr(VI) depends upon its particular species
whose etability and structure depends upon the acidity
of the medium. Chromic acid is a fairly otronc acid
(k« m 0.18, kg « 3.2 x 10 ) and In dilute aqueous 1*51«»15"?
oolutiona the following equilibria have been reported .
(a) H20r04 ^ 3* • HCrO*-
<b) ECrO~ —- •>» K* • CrO~
(c) 2HCr04 N CrsOj • HgO
(d) HCrg07 ^ S* • Cr20? (e) HgCrg07 ^ d+ • liCr^
206
The dicteri nation equilibrium (C) ie of crept
importance. In dilute acidic aqueous eolutiono* at con
centration® greater than 0.05H, the diehrosato ion (and
its protonnted opeelea) is the orodoainant specieo and
at lower concentration©,the monoser (and its protonated
species) predominates*•* . It hae also been confirmed
that dicbroiaata ion is a far weak oxidising agent than
acid ehromate ion* Very little, however, is known about
the chroniu© species in the at rone acidic medium*
It has been o«£G08ted by cany workers that electron
deficient cations auch as IlCrO and HgCrO^ are the moot
probable species26,154»155* Since the concentration of
sulphuric acid used is comparable to that used formerly•
it can safely be concluded that the protonated species
as shown above are the effective oxidising agent in our
system. .
It lo seen that increase in ionic strength
increases the rate of oxidation. Interpretation of theoe
data scene to be difficult as there cay be cany factors
which ££y cause a change in rate with changing ionlo
strength. The acid chromat3-dichromate equilibrium ia
a function of ionic strength for two reasons. Tirst.
increasing ionic strength will favour the formation of a
20?
divalent ion olid secondly, a divalent ion will have &
higher ion pair association consfceni then a uniralisnt
ion* Both of these effeote cause the equilibrium .
to ohlft towards the di«aro©at* ion && the ionic Qfcrsngtn
increase** fala would correspondingly deeroaae fcae ret©
of reaction* I t ia contrary to our fladlag* ends hence
tola explanation i s untenable* tfne deereaae in rate
oonetaat witfc ineroaelgg lonlo atreagta Indicates ©. reaction
fcstween oppositely aborted iona* But increase in rote with
iacrsaeiag ioa&o atiraagth I s oon®i©tant with e re&otlen
batttesn neutral molecule &nd enstrged spealoa # I t eeoise
reasonable beoauee too ^noting- aliphatic acid aoleeule i©
tmdoubteily «s neutral molecule &Rd aexavalest oferotaiuia in
© o&tloBie Bpmim HCrflJ* therefore st#p (B) of the recctlon
tsfecnenism 1© favoured by increasing lonlo ttrsneth*
The influence of chain length on the rate of ontidntion
of fatty soldo w&s determined end the obeerved order of
renotivity followed the eeqaeno© »ro»loni©<bi}i5yrio<; valeric*
Shie la the order of reactivity expected on the basis of nooek
and Krupicafea'a eieehaniaffi * the increase in the rate oonstr.nt
with ineraaelng earbon chain nay be du« to the greater number
of ©ethylene groupa or i t reay be due to the nuoleophilloity of
208
larger alkyl groups* a s i tua t ion sir l i a r to that found
ea r l i e r for the chronic acid oxidation of alcohols •
I t io also lmoim 5 1 , 1 3 3* l 4 7* 1 5 6» that earboxyl group
greatly inh ib i t s the chronic acid oxidation of carbon
chain, Hocek carried out the qual i ta t ive invcoticatlon
of the carboatyl group effect and attenptod to express th i s
influence on the baaio of h i s k inet ic data* Ce ©loo found
that the order of reac t iv i ty of fatty acids i o i n agree
ment with Hocek'o observat ion As the carbon chain
increases, the inductive effect of carboxyl group dicii-
nichco and hence tho increase in oxidation r a t e o i th
increasing chain length takes place*
I t io well Imovm that branching in tho/£-posit ion
to the reaction centre has a very pronounced effect on the
reaction veloci t ies and can cause changes in the ra te
constants of nany Orders of oacnltude • 2ho resu l t s
on the oxidation of branched chain acids show that the
replacement of one hydrogen by one methyl ftroup increases
the ra te by 20 tines* This i s conoistant sritth the fact
that methyl croups which are electron releasing cake tho
cethylene #roup cor© negative and thus f a c i l i t a t e the
attach by electronhi l ie species HCrOj. Tho hi-^h ra tes
of oxidation of branched chain acids can aloo be accounted
in the aaoe way*
209
In order to follow the effect of benccno ring on
the oxidation rate of a l iphat ic acids benzoic end
phenylaeetlc acid were talten. Benzoic acid t?ae hardly
oxidised but phenylaeetlc acid woo oxidised about 25
t ines faster than oropionic acid* the Increase of the
reaction r a t e cannot ho?7everf be at t r ibuted to the oxida
t ion of benzene ring v?hicfi i e hardly affected by chronic
acid as evidenced by the unreaetivity of benzoic acid
which i e fouaed eo the end-product.
ffte ra te of chromic acid oxidation of fat ty acids
in the presence of nannsnous or cerouo ions was found
d i f f icu l t to ncaoure. However* experiments were performed
with various concentrations of raanganeoe ( I I ) and cerium
( I I I ) ions . The r r t e s trore highly i r regular and,therefore,
no satisfactory conclusion could be drawn. ?ho fact i s
that there are many complications which are recponoible
for these i r regular resul ts* Firs t ly , various nancanese
s a l t s obscures the end point of an iodonetric t i t r a t i o n
(perhopo by catalysing the r i r oxidation of I""). Secondly,
the analyt ical procedure determines both the Cr(VI)
concentration and the concentration of manganese opecies
of oxidation s ta tes higher than tv?o. Several attempts
were made to find on analyt ical procedure which would
diotin&uioh between Cr(VI) and higher oxidation s t a tes
210
of atuiganeee and certu*. Bat no »uoh procedure could be
evolved* it was however, found that the amount of
chromic eoid consumed in the reaction mixture to which no
•angeneee (II) or oerlua (1X1) iono had been added* wae
more than that to which thoae iono had boon added* It
indicated that so»e retardation by those lone v?aa caused.
On the boeie of the reeulte which have been obtained
the rate law nay be written ce
The following meohanlBD which ie oonsiytant with the above
rate lew, involve© the direct transfer of methylene hydro*
gene &e hydride lone to the oxidising agent*
(1) HCrOj • SB* ~.„:> HOrOjj • Hg0
H O BO I II p» . I ||
(S) E - 0 • H • 0*&T * o-//SWlft B - 0 ~ G ~ C r ~ O H * K * I V l > ^ I
COgH C0g8
R 0, OH i <ril * „ * • i
(3) R - C • 0 ~ Cr * OH &&h a - C - 0 ~ C r ~ O B I J COgH COgH
H H
^,0 OH 0-H OH <-*+ I +mm+ I |
(4) B * 0 - 0 * Cr - OH * « £ • B • C ~ 0 • Or - QH • H* I I OOgH COgH
211
OH <« 1 O OH
I « I fast' " ' (S) S m 0 - 0 - Or »fflJfo.l&fr H *C * SO H • Cr « 0 * 8*
COJJU ' OH
C^ Ha^V *rf C3?0J • H*ljfr£l 'T^ eH^Olog
Q 0 ol+ O
(v) B ~ C ~ 0 ~ O « . » * Q «0y+ • OH Mt l . . ^ J? - C* • 00
0 0 II, H„0 11 .
C8) H • C ^ f g y ^ B • C - OB • H*
Ifaree and Hoeele reported that the oxidation of
methylene grotqp was #s two stag© prooess* In the f i r s t
stnp« a pa r t i a l ly developed e&rbeniua ion i s Some?-
(by hydride ion transfer)* the sooond at«$* l a the reaction
of thin species with Cr(I?) compound already formed in
the f i re t etts$e« l a our reaction aeoh«0>i^p equations fg)
snd (3) show the formation of carboniuia ion front the
fatty noid moloovOUu The fonwsition of eexbonium ions in
the chromic «cid oxidation of organic ooro^owiide has been
confirmed by Jfeeaoiu . I t l e reasonable to aeause
equation (S) an the rn te determining step einoe i t involves
the abstraction of hydride ion,(generally hydride shif ts
i re re la t ively slow processes)* ? mechanic* very
212
s imi l a r to t h i s has been pos tu la ted by Pos te r and
III cklnbottorn w fo r the chronic acid , oxidat ion of
©ethylene group i n the sa tura ted hydrocarbons*
H H
R - C - H * H g C r 0 4 -""> R - 0 - 0 - CrOgH >
R R
B - C - 0 - Cr(OH)g > RgCO.
R
fhe intermediate -^O-O.CrOgH postulated as coooon to
these oxidations was assumed to arise by abstraction of
a hydride ion to give a carboniuo ion capable of cojsbin-
ing with HCr03•'It is ouggested that the intermediate
- ^C-O.CrO^H way ©IBO be fonaed by direct attack of
chromium tri oxide on the carbon.
-J; C - U ^ ^ C ^ — ^ -^C - 0. CrOgH.
ttoen the corbonius ion has been formed i t p icks
up a water nolecule frois the solvent to g ive the complex
compound shotm i n equation ( 4 ) . This complex subsequently
breaks down to £lve keto acid and a compound of t e t r a v a l e n t
213
chromium. The fate of this intermediate (as shorn in
egn.6) is similar to that previously postulated * *
, The hydride abstraction mechanism in our system
is strengthened by the fact that groups which release
electrons, would be expected to facilitate such a reaction
and are observed to enhance the oxidation rate. She keto Q 0
acid 1© cleaved jfco give R - C and carbon dioxide* R - C
reacts with water rapidly forcing the lower acid. She
cleavage of keto acid can not be caused by direct attack
of chromic acid on the koto acid molecule but must result
from the action of sons unstable intermediate containing
chromium in an unusual valence state. She evidence for
it was obtained by adding manganese or cerous ions to
the reaction mixture. These ions are not oxidized by
chronic acid itself but the earlier work shows that
these ions react rapidly according to the equations
CrI? + En11 ^ Cr111 • Kn 1 1 1
C r" «. 0 aI« _ ^ c r m „ CeIV.
Furthermore, an unstable Intermediate containing penta-160
valcnt chromium also occurs during chromic acid oxidations
but arises only from tetravalent chromium by way of reaction
(6). Therefore, when Mn** or Ce^*"* sweeps away totravalent
chromium from solution, it renoves pentavalent chromium
214
as well* Hence no cleavage of keto acid takes place.
As the reaction under study ia very complicated,
no almiflcance can be attached to the thereodynaaic
paranetera. However, these functions have been calculated
and are tabulated below*
R AF+ -Ml* A S * Acid (Roal/aole) (Kcal/oole) (Kcal/oole) ( eu.)
Propionic acid Butyric acid
Valeric acid
Isobutyric acid
Isovaleric acid
Phcnylacetlc acid
17.0 18.4
20.7
14.7
11.5
17.9
27.2 26.9
26.7
27.3
27.2
27.3
16.3 17.7
20.0
14.0
10.8
17.2
- 30.8 - 26.1
- 19.1
- 37.5
- 46.5
- 28.4
It is seen that the value of A ? * is the aanc in
all the acide. But the values of energy of activation E
and A H^ however, increase «tdth the increase in chain length.
Thooo vrluea are comparatively low for branched chain acids.
It is well known that if As* is positive, the formation
of activated complex is more probable and the reaction is
fajjt while negative entropy of activation indicates alow
reactions. A comparison of A S * values for straight
chain acids justifies th© observed order of reactivity,
valeric> butyric > propionic.
215
The high ra tes of oxidation in the preoence of
acetic acid can be explained by assuming that in the
solvents containing acet ic acid, noot of the chromic acid
i s present as an acetyl derivative CHgCOOCrO H or i t s
conjugate a d d CII-COO CrO^Hg - with an oxidising power
considerably higher than that of even chrooic acid or
chronacldiuB ion. I t i s evident that the replacement of
a hydroxy1 hydrogen by an acetyl group would considerably
decrease the electron denoity on the central chrooiuia
atocj and increase i t s e lectrophi l ic reac t iv i ty and hence
the greater oxidizing power.
Another explanation which seems a t t r ac t ive i s that
the reaction cjechaniais involves the t ransient formation
of carbonlum ions. Ifho length of the l i f e of a corbonium
ion depends upon the nuoleophilic properties of a solvent. l f i l I t has been reported that increasing acet ic acid
concentrations s t ab i l i s e e carboniun ion. S?huo a greater
concentration of acet ic acid should favour a mechanism
that leads to such an intermediate* I t has also been
reported (Hall and Spengeman, reported a t the Kansas City
meeting of the A.C.S. April , 1936) on the bas is of more
extensive data, that a solution of sulphuric acid in
glacial acetic acid i s much nore acidic than that of the
same sulphuric acid concentration in water.
216
The high rate of oxidation of phenylacetic acid
io also consistent with our mechanism because phenyl
group stabilises the carbonius ion due to resonance.
H H J /
4 / - C - COOH < > u"/ 0 C ~ C00H <",'>
H +
+ V—/*" C " C00H
The reaction which is the subject of the present
study had to be followed in a taedium of considerable
complexity. It iGf therefore# unlifcoly that any suggested
reaction scheme Bill be susceptible to rigorous analysis.
B I B L I O G R A P H T
217
1. Hanpton, J . , Leo, A . , and t7esthei iaer , P.II. «?. AD. Chca. S o c , 7 8 , 306 ( 1 9 5 6 ) .
2 . Cawley, J . J . , and Eesfcaelraer, F.H. i b i d . , 85,177 ( 1 9 6 3 ) .
3 . Hooher, TJ.A., and Lanjjeralc, n .O. i b i d . , 7 1 , 286 ( 1 9 4 9 ) .
4 . H o i d i g , H.A., Funck, B . L . , V/rich, R . , Baker , K. , and i t r e l a e r , t? . f
i b i d . , 7 2 , 4617 ( 1 9 5 0 ) .
5 . Bowden, K.» I f e i l b o r n , 1.14., J o n e s , E .H.H. , and Ueodon, B . C . I . J . Chen. S o c , 1946, 3 9 .
6 . Bovjrann, t ! . I . , t loore , C.B. , Deutoch, H.H. , and Hartman, J . I J . T r a n s . Kentuclry Acad. S c i , 14, 33 ( 1 9 5 3 ) .
7 . F a l s e r , L . F . , J . Am. Cham. S o c , 7 5 , 4386 ( 1 9 5 3 ) .
8 . Poos , 0 . 1 . , Ar th , O.K., Buy le r , R .R. , and S a r e t t , L.H. J . As* Chen. S o c , 7 5 , 422 ( 1 9 5 3 ) .
9 . H O I U E , J . R . , J . QrR. Chen. , 2 6 , 4814 ( 1 9 6 1 ) .
10 . r toaher , 7 .A . , and F r e i o o , O.n. J . AD. Chen. S o c , 7 5 , 5605 ( 1 9 5 3 ) .
1 1 . Oppcnauer, R.V., and Oberrauch , H. Anal08. Asoc. Qtiim., Arr*, 3 7 , 246 ( 1 9 4 9 ) .
1 2 . Leo , A. , and Tes tho i - e r , F.H. J . AD. Cham. S o c , 7 4 , 4383 ( 1 9 5 2 ) .
1 3 . Anbar, H . , Doatrovoky, I . , Samuel, 0 . , and Yof fe , A.D. J . Chen. S o c , 1954, 3603 .
2
Zeiss , H.U., and Hathewa, C.H. J . AD. Chem. Soc . , 7 8 , 1694 (1956),
TJesthoiser, P.H., and Bovick, A* J , Ghee, Phys . , 11 , 506 (1943).
Cohen, n . , and t?estheiner, F.H. i b i d . , 74 , 4383 (1952) .
Kuivilu, H.G., and Beeker, T?«J# i b i d . , 74 , 5329 (1952).
Antony, V., and Chnt ter^ee , A.ft. 2 . Anorg. Allgera, Checu, 280, 110 (1955) .
Scbreiber , J . , and Eschenraosher, A. Helv. Chira. Acta. , 38 , 1529 (1955).
Svar t , H. , and Franc i s , P . S . «f. Am. Chera. S o c , 7 7 , 4907 (1955).
Bocek, J . , and Kruplcka, J . Co l l . Czech. Checu Corjaun., 23 , 2068 (1958).
Chnterjee, A.C., and Antony, V. i,. Physik, Chen. (Le ipe ig ) , 210, 103 (1959) .
Krauaa, R.I»., 2. IJaturf orach, 136, 199 (1958).
Klaniong, U., Acta. Chits. Scand. 11 , 1313 (1957) 12, 576 (1958).
Rocek, J . , Testheiraer, F .H. , Eschenraosher, A., Holdovanyi, L . , and Schre iber , J . Helv. Chia. Acta . , 4 5 , 2554 (1962).
Ttocek, J . , and Krupickc, J . Cham.and Ind. (Lond. ) , 1668 (1957).
"Veatheimer, P.H., end Chang, Y.*?. J . Phy. Chen., 63 , 438 (1959) .
2
I?wart, II . , and F ranc i s , P .S . J . AEU Chen». S o c , 77 , 4907 (1955).
OrahaB, G.T.H., and tTesthelmer, F*H. i b i d . , 80, 3030 (1958).
Cowley, J . T . , and r eo the ine r , F.H. Chern. and Ind . (London), 656 ( I960) .
Lansbury, P .T . , F a t t l s o n , U.A., and Dlchl, J . r . Cheis. and Ind. (London), 653 (1962).
Sager, F., J. Am. Chern. Soc, 78, 4970 (1950).
Rocek, J. Col l . Csech. Chexn. Coin . , 23 , 833 (1957).
25, 375 (I960)-
Black, R., and Waters, ?".A. J . Choc. S o c , 594 (1949).
Chnt tc r jee , A.K.. and nwkherjee, S.E. , Z. Physlk Chera. (Lelpsslfj), 207, 372 (1957) | 208, 281, (1958)j 210, 166 (1959).
Chantf, Y.U. , and r e s t h e l o e r , F.H. J . An. Chen. S o c , 82 , 1401 ( I960 ) .
Criegee, R., Kraf t , L . , and Rpnk, R. Ann., 507, 159 (1933) .
Bu i s t , G . J . , and Bunton, C.A. J . Chea. S o c , 4580 (1957) .
Tiocek, J . t and Tea the icer , F.H. J . Am. Chem. S o c , 84 , 2241 (1962).
Luechi, E. B o l l . Sol . Fac Chi-.. Ind . Bolo^nn, 208, 333, (1940) Gazs. Chin. I t p l . , 7 1 , 729, 752 (1941). riber<*, K.B., and U l l , T. J . Am. Chern. S o c , 80 , 3022 (1958).
220
42. 'Tibcrc, K.B., and Stewart, B. ibid., 77, 1786 (1955).
43. Rocek, J., te t rahedron L e t t e r s , ^ o . 5 , 1 (1959).
44 . Chattor3ee,A.K., and Hukherjee, 8.K. J . An. Chora. S o c , 80 , 3600 (1958).
4 5 . ICemp, T . J . , end Meters, tf.A* P r o c Roy. S o c , A274, 400 (1963) .
46 . ( a ) B e l l , R .P . , B. Barwent, B.B.B., f r a n s . Faraday, S o c , 46 , 34 (1950).
46 . (b) B e l l , R .P . , and Clunie , J .C . i b i d . , 48 , 439 (1952) .
46 . (c ) B e l l , B.P.,Band f H.H.. and (Uiss) *Tym*e-Jones,K.D.A, i b i d . , 52, 1093 (1956) .
47 . B o l l , R .P . , and Rand, n.H. B u l l . Soc. Chinu, 115, 115 (1955).
48. Fuson, B.C., Advanced Organic Chcnis t ry . John rr i l ley & Sons. I n c . , Hec? York, fl.Y. 1954, p .366.
49 . Hers, J . H . , and Ca te r s , V;#A. Bias . Farad. S o c , Ho. 2 , 106 (1947).
50. Tibere , K.B., and Richardson. t?.H. J . Am. Cheru S o c , 84 , 2800 (1962).
51. Petit, 0. Bull. Soc Ohio. France., 12, 568 (1945).
52. Goeda, £., and Taroma, K.I. FJippon Ka#aku 2asshl, 83, 1216 (1962).
53. Best, P.A., Lettler, J.S., and Tabes, T.A. J. Chen. Soc, 1962, 822; Littler, J.S., ibid, 1962, 827, 832.
221
Tiber/?, K.B., and Gotzke, A.L. Unpublished r e s u l t s *
Hocek, jr . , and Rlolh, Sr.A. P r iva t e Conasunlcation.
Guyot, J . , and Slnon, L . J . Corapt. rend. Acad. S c i . , 170, 736 (1920).
Coves, C.B. Ann., 167, 357 (1873) .
B e l l a t e l n , F . , and Ktirbatow, A. Ann., 202, 215 (1880) .
Wendland, H«, and LaLonde, J. Ore. Syn. C o l l . , Vol. IV, 757 (1963).
Abell , ft.B., «T. Chest. S o c , 1951, 1379.
F i t t iC t 8«# Ahrena, tr . , and nn t the ides , L. Ann., 147, 15 (1868) .
Slack, E . , and r a t e r s , '"T.A. J . Chen. S o c , 1948, 1666.
Ogata, Y. , and Akiraoto, H. J . 0r&. Chem., 27, 294 (1962).
Brandenber^er, 3.G. , f 'aas, I.."?., and Pvoretsky, I . , J . Arc. Chen. S o c , 8 3 , 2146 (1961).
Friedman, L . , F l she l , D.L., and Schechter , H. J . Org. Chem., 30, 1453 (1965).
Evan©, K.B., and <7vano, R.J . Tetrahedron, 8 , 313 (1960) .
Paul, E.A., and Lon«*, F.A. Chen, rev., 57, 1 (1957).
Behr, A. Ber., 5, 277 (1872).
222
B l i t z , II. Ann., 296, 219 ( 1 8 9 7 ) .
Bockerauller , !T.f end J a n s s e n , R. Ann. , 542 , 166 ( 1 9 3 9 ) .
B a r b l e r , P . , and Locquln , R. Conpt. r end . Acad. S e t . , 156, 1443 ( 1 9 1 3 ) .
n e l a n d , H . t S c h l l c h t i n g , end J a c o b l , R. 2 . P h y s i o l . C h e c , 1 6 1 , 80 (1926 ) .
B e r l i n , A.A., Bavanteov, A.D. . and K a l l l o p l a , L.K. J . Appl . Cheia. 0SSR., 18 , 217 ( 1 9 4 5 ) .
Hickinbot to ia , U . J . , ana T:ood, D.G.I1. H a t u r e , 168, 33 ( 1 9 5 1 ) .
Hickinbot to ia , T7.J. , Hoftg, B.R. , and flood, B.G.tl. J . Chen. S o c , 1954, 4400 .
Hickinbot to ia , T7.J. , P o t o r s , D . , and food , D.G.T3. J . Chem. S o c , 1955, 1360*
Z e i s s , H.H. , and Zwansslg, F.R. Chen, and Xnd. (London) , 5 4 5 . 1956. J . Ad. Chera. S o c , 7 9 , 1733 ( 1 9 5 7 ) .
Davis , U.A. , and H i c k i n b o t t o n , U . J . J . Chem. S o c , 1953 , 2205.
F l k e , J . , *3vpns, R . H . , Longo, A.G., and Tnojaes, G.H. J . Chen. S o c , 1954, 4 5 1 .
Hares , F . , and Rocek, J . C o l l . Czech. Chen. Cocn . , 2 6 , 2370 ( i 9 6 0 ) .
nock, J . and Toroo, F . i b i d , 2 4 , 2741 ( 1 9 5 9 ) .
Rocek, J . i b i d , 2 2 , 1509 ( 1 9 5 7 ) .
223
Jtouriia, P . , and Sykva. R. i b i d . , 26, 2511 (1961) .
F ieaer , L . F . , J . Ai% Chea. S o c , 70 , 323? (1948).
Bredt , J . , and P l a t a n , P . J. Prakt, Cbeo., 115, 48 (1927).
Sager, E.F., and Brodley, A., J« Am. Caem. Soc, 78, 1187 (1956).
Sager, W.P. ibid., 78, 4970 (1956).
Roccfc, 3, Coll. Ccech. Chora. Cotsmun., 23, 833 (1958).
Clberg, K.B., and Haenthel, 1. tetrahedron., Vol. 20, 1151-61 (1964).
Rocek, J. Tetrahedron Letters, 135 (1962).
Snetblage, ll.C.S., n Rec. Trav. Chi-., 59, 111 (1940).
Azanares, J.I., and Kam$ ^«B.V. Analeo. Real. Soc. Kspan. Pis. Qui©. (Uadrid) Scr, B50, 545, 656 (1954).
Karoo, F., and Rocok, J. Col l . Czech. Cheta. Coxosun., 26, 2389 (1961) .
Kreulen, D.J.T., and Ter. Horot, D.T.J. Rec. Trav. Chin., 59, 1165 (1940).
Snethlage, H.C.3. ibid., 60, 877 (1941).
Eahajanl, A.V., and Dhattacharya, A.K. Proc. Natl. Acad. Sci. India, sect A23(2) 05 (1954).
224
97* Punffor, E . , and d r o o p i e r , J . J* I n o r g . H u c l . Chen . , 5 , 123 ( 1 9 5 7 ) ,
9 8 . Maha^anl, A*Vm Proc. f*atl. Acad. Sci. India, sect. A26(l), 49(1957)
9 9 . F e o t h e i o e r , F .H. Ches . r e v . , 4 5 , 419 ( 1 9 4 9 ) .
100. Chapman, E . T . , and Sc&th, K.H* J , Chem. Soc« f 2 0 , 173 ( 1 6 6 7 ) ,
101 . Coninck, F .O . I t e . , Chen. 2 e n t r . , 1906, 1 , 4 4 9 .
102. B e i l e t e i n , P . , and Elcgand, 1* B a r . , 17, 840 ( 1 8 8 4 ) .
103. Bakore , G.V., and H a r a i n , S . J , Chen. S o c , 1963, 3419 .
104. Kwart , H.» and F r a n c i s , P . 3 . J . Am. Chen. S o c , 7 7 , 4907 ( 1 9 5 5 ) .
105 . Tocher , 12. J . Chem. Edn . , 3 5 , 207 ( 1 9 5 8 ) .
106. H a t c h . , and G r u n ^ e i r>. B e r . , XI , 1053 ( 1 8 7 8 ) .
107. Dakin, H.D. J . B i o l . Chem., 4 , 77 ( 1 9 0 8 ) .
108. Dakin, U . S . i b i d . , 4 , 9 1 , 227 ( 1 9 0 8 ) .
109. Dakin, H.D. Am. Chem. J . , 4 4 , 41*48 ( 1 9 1 0 ) .
110. Chu t t e rbuck , P . C . , and Haper, H . S . , Blochem. J . , 19 , 385 ( 1 9 2 5 ) .
225
111. Allen, R.H., and TTitceiaann, E . J . J. An. Chen. Soc, 63, 1922 (1941).
112. Ogata, Y.t and Sasaki, Y. tetrahedron, 21, 3381 (1965).
113. Hatcher, tf.H., and Hill, A.C. frana. Hoy. Soc. Can. Sect(III)(3)t 23 (1929).
114. Berozin, I.V. Ugarova, K.N.,Panish, A.H., and Khrolova, O.R. Eh. Pis. Khlm., 39(2), 369 (1965).
115. Csanyi, L.J. Acta. Chin. Acad. Sei. Hungary., 21, 35-40 (1959).
116. Poster, L.O., and Payne, J.H., J. AG. Chen. Soc, 63, 223-25 (1941)*
117. Kline, Itm Blochcn. 2., 220, 11? (1930).
118. Dinitrov, D., and Hatan, V., Godiohnik Khicu Teohnol Inst., 8(2), 12? (1961).
119. Ileunhoeffer, 0., and Hatha, J. J. Prakt. Chera., (4), 2, 84 (1955).
120. Deupre, J. P., and Lyons, R.E. Proc. Indiana, Acad. Sei., 46, 101 (1937).
121. Pleury, P., and Boisoon, R. J . Pharm. Chin. , 30, 307, 16 (1939).
122. Kore t te , A., and Gaudefroy, 6. Coiapt. r end . , 237, 1523 (1953).
123. Cl i f fo rd , A.A., and Waters, " .A. J . Chec. S o c , 1965, 2796.
124. Polonovski, El, Corapt. r end . , 178, 576 (1924).
226
125. Polonovski, K.» and LlndcnberE, A. I b i d . , 209, 546 (1939) .
126. Su l ly , B.D. J . Chero. S o c , 1942, 366.
127. Fe ig l , F.» 'Spot Tests in Organic anelyoio» Elsv ie r Publlohing Company, 1960. t pp# S69f %2%t
128. Kenyon, J . , end SyBons, H.C.B. J . Chen. S o c , 1953, 2129.
129. Podo, J . U . P . , and TT.A. Ca te r s . i b i d . , 1956, 717.
130. Beefcvlth, A.L .J . , end Goodrich. J . B . Aust. «J. Chen., 18, 1023 (1965).
131. Bacon, H.G.R., and B o t t , R.n. Chen, and I n d . , 1953, 1285.
132. P i eb t e r , F . , and Heer, J . Helv. Cbim. Acta . , 18, 1276 (1935) .
133. Cnaon, J . Feeaenden, S«, and A&re, C.I.. T e t r a h e d r o n , ^ , 289 (1959) .
134. Oakin, H.D. J . B io l . Chem., 4 , 419 (1908).
135. Dakin, H.D. i b i d . , 4 , 424 (1908) .
136. Jones , R.O., and "ocLecn, I . S . , Biochen. J . , 29, 1877 (1935).
137. Daflley, S . , Pewster, n .K. , and Heppold, F.C. J . Bac t . , 63, 327-36 (1952) .
138. Hockenfeull, D .J .D. , t a l k e r , A.D., ffllkln, G.B., and binder , F.G. Blochem. J . , 50 , 605 (1952).
22?
139. Spiro , K. Hclv. Chlo. Acta , , 4 , 459 (1921).
140. Prfi2faeval ,skll, E#S. J . Ruso. Phys. Chero. S o c , 49, 567-72 (1917-18).
141. Skraup, S . , and Schwanberger, "R. Ann., 462, 135-58 (1928) .
142. Dlni t rov, B. , and Stef&nova, A.D., Godlshnik Khim. $eehnol I n s t . , 11(2) , 1S9 (1964) .
143. Bara&at, H.Z. , r ahab , T..P.A., end El-Sadar , n.H. J . Chen}. S o c , 1956, 4685.
144. KretKl, K*» Royos, P .E . , end S i l b e r a a g e l , H. llontaoh. Chen., 9 1 , 219-26 (1960) .
145. Hor i l , Z . , and Sakurai , R. J . Pharm. Soc. Japan, 77, 1-2 (1957) .
146. Bacon, B.G.H., and Hanna, ^.J.SU P r o c Ches. S o c , 1959, 305.
147. ITakaniohi, K., and F i e se r , L .P. J . An. Chen. S o c , 74 , 3910 (1952) .
148. ""otanabe, T . , Furutearra, W.» end Oal, S. B u l l . Chen. S o c , J apan . , 4 1 , 242 (1968) .
149. Footer , 0 . , and Hicfcinbotton, tf.J. J . Chen:. S o c , 1960, 680.
150. Loo, D.J . , and Stewart , H. , J . Am. Chen. S o c , 86 , 3022 (1965) .
151. Reuse, J . B . , and i&esan, W. J . An. Chora. S o c , 56 , 2238 (1934).
152. Tonp, J . Y . P . , and Kln<r, P.L. I b i d . , 75 , 6180 (1953) .
228
153. Ba i ly , 17., Carr lnf ton , A., Lo t t , K./UIC., and Synona, I3.C.R. J . Chem. S o c , 1960, 390.
154. L e v i t t , I».S. J . Org. Chen., 1297 (1955).
155. Tatera , U.A. Qvart, r e v . , 18, 277 (1958) .
156. Snethlage, H.G.S. Bee. Trav. Chin. , 56 , 873 (1937) .
157. Xngold, O.K., S t r u c t u r e and Mechanise! i n Organic Chemistry*• Cornell TJniv. P r e s s . I t h a c a , 1953.
158. Hares, P . , and Hoeelc, J . Co l l . Czech. Chen. Coi&cun., 26, 2355 (1961) .
159. Heesoiu, I . , end IJensItzescu, C D . Chen. & Ind. , 1960, 377.
160. ra tanahe , U.» and Ccetheiiaer, P.H. J . Chem. Phys . , 17, 61 (1949).
161. Dostroveky, I . , and Samuel, D. J . Chen. S o c , 1954, 658.