organic chemistry organic chemistry: the study of carbon-containing compounds -- molecular shape is...
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Organic Chemistryorganic chemistry: the study of carbon-containing
compounds
-- molecular shape is crucial
3-D structure ofsalicylic acid
3-D structure ofacetylsalicylic acid
(aspirin)
Honors Chemistry
Carbon is unique amongthe elements because:
it can have up to four bonds per C atom --
single, double, or triple bonds
--
--
it can form REALLY long chains of C atoms
its bonds are strong
–C–C– C=C –C=C–
Drawing Organic Structures
Butane: C4H10
C C C C
H
H
H
H
H
H
H
H
H
H
CH3 CH2 CH2 CH3
CH3CH2CH2CH3
CH3(CH2)2CH3
Shortcuts make structures easier & faster to draw
Line Structure• Only shows bonds• C atoms assumed at each end
and intersection of bonds• H atoms not shown• Assume 4 bonds to each C• Fulfill C’s 4 bonds by adding H’s
Lewis Structure
Condensed Structures
Carbon Atoms
Basic Definitions
hydrocarbons: compounds containing only __ and __
alkanes: hydrocarbons having only ______ bonds single
-- –anes are saturated
–C–C–C–
–C–
H H
HHH
H
HHHH–C–C–C–C–
H H HH
H HH H HH
H C
alkenes: hydrocarbons having at least one ____ bond C=C
alkynes: hydrocarbons having at least one ____ bond C=C
C=CH
C
H
HH H
H
H–C–C=C–C–C–C–H
H
H
H H H
H H H
CH2CHCH3
CH3CC(CH2)2CH3
The simplest alkyne,ethyne (i.e., acetylene)– C2H2 – is the fuel in oxyacetylene torches.
aromatic hydrocarbons: benzene and compounds w/a benzene-related structure
-- –enes, –ynes,and aromaticsare __________ unsaturated
(C6H6); six C atoms in a planarring w/“tweener” bonds
August Kekule(1829–1896), whoclaimed that a dreamgave him insight into the structure of benzene.
“Finer-Point” Definitions
Straight-chain compounds have…
a single carbon backbone.
Branched-chain compounds have…
a main carbon backboneAND one or more branches
Substituted compounds have…
one or more H atomsremoved, with otheratoms (often halogens)in their place(s) Br
CH3(CH2)3CH3
C8H18
C5H11Br
C5H12
CH3CH2CH2CH2CH3
Branches and H-replacing atoms/groupsare collectively called… substituents.
–C–C–C–C–C–C–
HCl
HH
HCl
HH
HCl
HHPolyvinylchloride (PVC) is a material
made of long-chain carbons that havemany chloride substituents.
Functional group: a characteristic pattern that makes up a portion of a larger m’cule
-- specific atoms, specific bonding arrangements
-- importance: fgs largely determine the behaviorof their m’cules
–OH
alcohols ketones carboxylic acids
–C–
=
O
–C–
=
O
OH
-- several examples of fgs:
O O
OH
–COOH
Types of Organic CompoundsClassified according to functional groups
Alkane
Alkene
Alkyne
Haloalkane
Alcohol
Ether
Ketone
Aldehyde
Carboxylic acid
Amine
Amino acid
AmideO
H
O
NH2
O
OH
O
H2NOH
O
OH
Cl
Br
NH2
C C
O
Many organic compoundsare combinations ofseveral categories.
Cl
OH
Cl
O
OH
O Br
C6H11Br
Brsub.
br. + sub.
C10H21Cl
fg + sub.
C6H13ClO
fg
C6H12O2
fg + sub. + br.
C9H17BrO
Organic Nomenclature
Memorize the prefixes that tell the # of C atoms in the longest, continuous chain.
1 =2 =3 =4 =5 =6 =7 =8 =9 =
10 =
meth–eth–prop–but–pent–hex–hept–oct–non–dec–
pent–
non–
dec–
hept–
Naming Straight-Chain Alkanes
1. Find the longest continuous chain of C atoms. Choose the appropriate prefix.
2. The name ends with –ane.
Provide the counterpart to the given.
propane
heptane
(C3H8)
(C7H16)
Alkanes: modification for substituent hydrocarbon (HC) groups
1. Number the “longest chain” carbons. Start with the end nearest a branch.
2. Name and give the #ed location of each substituent.
-- HC substituent groups use the prefixes, but end in –yl.
3. List substituents in alphabetical order.
(i.e., branches)
Provide each counterpart.
4-ethyl-2-methylhexane
octane
1
2
3
4
5
6
7
8
5-ethyl-3-methyl
(C11H24)
(C9H20)
Alkanes: modification for non-HC substitutions
1. The “longest chain” MUST “hold” the substituent.
-- example substituents:
–NO2 –NH2 –F –Br –I nitro amino fluoro bromo iodo
2. Number the chain carbons, starting with the end nearest a substituent.
-- A non-HC substituent takes precedence over an HC branch.
3. Name and give the #ed location of each substituent.
-- If necessary, choose #s so that their sum is as low as possible.
Provide each counterpart.
3-bromo-2-chlorohexane
heptane
2-methyl-1-nitrobutane
heptane2-amino-6-nitro-3-propyl
2-ethyl-1,1-diiodo I
I
Cl
Br
NO2
NH2 NO2
Alkanes: modification for cycloalkanes
-- Use the cyclo- prefix before the word “alkane.”
Provide each counterpart.
1-bromo-1-chloro-2-methylcyclopentane
ethyl
Br
Cl
(C6H10BrCl)
(C8H16)
cyclohexane
Naming Alkenes and Alkynes
1. The C-chain MUST include the multiple bond. Use –ene or –yne, as appropriate.
2. Number so that you get to the multiple bond ASAP.
-- The multiple bond takes precedence over branching or substituents.
3. Use di- or tri- right before –ene or –yne if you have two or three multiple bonds.
Polyunsaturated fats and oils containdouble and/or triple bonds.
Provide each counterpart.
1-butyne
2-butyne (C4H6)
(C4H6)
7-methyl-2,4-nonadiene
(C10H18)
(structural isomers)
7-fluoro-6-methyl-3-octyne
Cl Cl
Cl 3,3,4-trichlorocyclohexene
F
(C6H7Cl3)
(C9H15F)
Benzene,Phenol,
and Toluene
These are the “Big Three” aromatic compounds.
(“FEE nahl” or “fn AHL”)
benzene phenol toluene
For phenols and toluenes, the C to which the–OH or –CH3 is attached is carbon #1.
CH3OH(C6H6)(C6H5CH3)(C6H5OH)
Provide each counterpart.
bromobenzene
ethylbenzene
2-propylphenol
Br
OH
(C6H5Br)
(C8H10)
(C9H12O)
CH3
I
I
3,4-diiodotoluene
OH
NH2H2N
2,6-diaminophenol
CH3
NO2O2N
NO2
2,4,6-trinitrotoluene
ortho- para-dichlorobenzene
meta-
1,2-dich
lorobenze
ne
Cl
–Cl
Cl
–Cl
1,3-dich
lorobenze
ne
Cl
Cl
1,4-dich
lorobenze
ne
For this class, if a benzene ring isconnected to an interior C atom in a hydrocarbonchain, it is called a phenyl (“FENN uhl”) group. It
lookslike THIS and has the formula…
–C6H5.
Provide each counterpart.
2-bromo-2-chloro-3-phenylpentane
3-nitro-2,4-diphenylhexane
3-amino-3-phenyl-
ClBr
NH2 NO2
1,1-dibromo-3-phenylBr
Br
1-butene
cyclopentane
Alcohols
Alcohols contain the hydroxyl group.
Primary (1o) alcohols have one “R” group;secondary (2o) have two;tertiary (3o) have three.
-- low molar mass alcohols are soluble in…polar solvents, due to the polar nature of –OH
-- all alcohols have higher BPs than their parentalkanes (due to HBFs btwn. adj. m’cule’s OH grps)
–OH
–C–
H
OH
– –
RH
–C–
R
OH
– –
RH
–C–
R
OH
– –
RR
Naming Alcohols
1. Without being redundant, specify the location of the OH group(s); the suffix is –ol.
2. Use di- or tri- right before –ol if you have two or three OHs.
1-propanol
1,1-propane
3-ethylcyclohexanol 3-ethylphenol
–OH
Provide each counterpart.
OH OHOHOH
diol
5-bromo-2-propyl-6-chloro-1-hexanol
HO– Br
–Cl
1,2,4-
HO
HO OH
triol cyclopentane
Many pharmaceuticals(including aspirin, shown above)
contain hydroxyl groups.
Ketones Aldehydes Esters CarboxylicAcids
Func
tiona
l gro
ups
cont
aini
ng th
e ca
rbon
yl g
roup
Nam
es e
nd in
–on
e,w/t
he C
in t
he c
arbo
nyl
havi
ng t
he lo
wes
t po
ssib
le
num
ber.
Nam
es e
nd in
–al
,w/t
he C
in t
he c
arbo
nyl
bein
g C
#1.
The
C in
the
car
bony
l is
C #
1.
Wha
teve
r is
att
ache
d to
the
–O–
is n
amed
firs
t, t
hen
the
nam
e en
ds in
–oa
te.
Nam
es e
nd in
–o
ic a
cid,
w/t
he C
in t
he
carb
onyl
bei
ng C
#1.
–C– =
O
–C–
=
O
OH –C–
=
O
H –C–
=
O
O–
Provide each counterpart.
3-hexanone
3-phenylbutanal
5,6-difluoro-
O
O
O
H
O
propyl
OF
F
oate propan
2-heptanone
2-ethyl
3-propylhexanoic acid
-2-methyl
4,4,4-trifluorobutanoic acid
O
HO
OH
O
O O
OH F
FF
pentanal
oate octan methyl
Other Functional Groups to Recognize
Ethers Amines Amides (“EETH erz”) (“uh MEENZ”) (“uh MIDZ” or “AM idz”)
–O– –N–C–N
=
O
“coca-ine”“caffe-ine”“Tatoo-ine”
Organic Reactions
combustion of hydrocarbons OR compounds w/only C, H, and O: products are…CO2 and H2OWrite the equation for the
completecombustion of 2-methyl-2-
pentene.
Write the equation for the completecombustion of ethylbutanoate.
C6H12 + O2 CO2 + H2O6 69
O
O
C6H12O2 + O2 CO2 + H2O6 68
substitution: an H atom is removed and “something else” is put in its place-- In halogenation, a _______ atom replaces an H. halogen
Write an equation for the reaction
between ethane and chlorine.
+ Cl2 –C–C–H
HH
HHH
–C–C–Cl
HH
HHH
+ HCl
If more chlorine is provided, the reaction will produce...
AND SO ON.
–C–C–Cl
HH
HHH
+ Cl2 –C–C–Cl
HH
ClHH
+ HCl
Substitution occurs with aromatic compounds, too.
+ Br2
catalyst
+ CH3CH2Clcatalyst
Br
+ HBr
+ HCl
Ethylbenzene is an importantintermediate in the production
of styrene which, in turn, isused to make polystyrene.Roughly 25 million tons of
ethylbenzene are produced and used every year.
addition: a multiple bond is broken and two “things” are inserted
+ Br2
H C=C
H
H H–C–C–Br
HH
BrHH
+ HBrH
C=CH
H H–C–C–Br
HH
HHH
+ H2OH
C=CH
H H–C–C–OH
HH
HHH
H2SO4
H–C–C–C–C–H
H
H
H
H
+ Cl2 –C–C=C–C–
Cl HH
H HCl HH
A specific addition rxn is hydrogenation, in which__ is added across a multiple C-C bond.H
-- requires a catalyst (usually a finely-divided _____) to rupture the multiple bond metal
–C–C–H
HH
HHH
+ H2
H C=C
H
H H
catalyst
Another addition reaction is polymerization.
“lots” of ethylene
H C=C
H
H H H C=C
H
H HH C=C
H
H H polyethylene
–C–C–C–C–
HH
HH
HH
HH
condensation(or elimination,or dehydration): _____ is a productwater
-- One reactant provides an __, the other provides an ___.
HOH
CH3CH2OH + CH3OH CH3CH2OH + CH3OH
NO2
+ H2O+ HNO3
H2SO4
CH3CH2–O–CH3 + H2O
wateralcohol alcohol an ether
Complex proteinmolecules are
made fromcondensation
reactions ofamino acids.
-- Amides can be formed in condensation rxns between carboxylic acids and amines.
Write the equation for the reaction betweenbutanoic acid and nitrogen trihydride.
O
OH
+ NH3
O
NH2
+ H2O
carboxylic acid amine amide water
Ammonia is the simplest amine.
Esterification is a condensation reaction between acarboxylic acid and an alcohol.
Write the equation for the reaction betweenbutanoic acid and 1-butanol.
O
OH HO
+
O
O
+ H2O
butanoatebutyl(the active substance in
the characteristicflavor/odor of pineapple)
Write the equation for the reaction between3-phenyl-2-propenoic acid and ethanol.
O
OH
HO +
H2O +
-3-phenyl-2-propenoate
(the active substance inthe characteristic
flavor/odor of cinnamon)
ethyl
(i.e, ethyl cinnamate )
“When in doubt, make water.”
Mr. B
O
O
