research article efficient and rapid solvent-free...

Hindawi Publishing CorporationJournal of ChemistryVolume 2013 Article ID 642479 7 pageshttpdxdoiorg1011552013642479

Research ArticleEfficient and Rapid Solvent-Free Acetylation ofAlcohols Phenols and Thiols Using Catalytic Amounts ofSodium Acetate Trihydrate

Mohammad M Mojtahedi and Shamim Samadian

Department of Organic Chemistry and Natural Products Chemistry and Chemical Engineering Research Center of IranPajouhesh Boulevard 17th Km Tehran-Karaj Highway PO Box 14335-186 Tehran 14968-13151 Iran

Correspondence should be addressed to Mohammad M Mojtahedi mojtahediccerciacir

Received 29 May 2013 Accepted 21 July 2013

Academic Editor Stojan Stavber

Copyright copy 2013 M M Mojtahedi and S Samadian This is an open access article distributed under the Creative CommonsAttribution License which permits unrestricted use distribution and reproduction in any medium provided the original work isproperly cited

Under solvent-free conditions different alcohols and phenols were efficiently acetylated at room temperature within short timeperiods by using acetic anhydride in the presence of catalytic quantities of sodium acetate trihydrate which is a very inexpensiveand mild reagent Thiols were also shown to behave equally well under the same conditions Chemoselective protection of lesshindered alcohols in the presence of bulkier homologues and phenols in the presence of alcohols was achieved using competitiveexperiments

1 Introduction

Protection of alcohols and phenols is one of the most com-mon synthetic strategies utilized to mask hydroxyl func-tionalities during multistep synthetic procedures [1 2] Inaddition O-acetylation procedures are widely employed forthe protection and purification of various natural and syn-thetic products containing carbohydrate substructures [3ndash5]Among various hydroxyl groups protecting moieties acetylis perhaps the most frequently used group due to the ease ofintroduction and its stability [6 7] In addition the acetateproducts can be efficiently converted to their respective origi-nal alcohols using variousmild procedures [8 9] Acetylationof alcohols is traditionally carried out in the presence ofexcessive amounts of acetic anhydride or acetyl chloride andan amine base [10] More efficient alternative methods aredeveloped in recent years using Lewis acids [11ndash16] solidsupports [17ndash23] microwave irradiation [24ndash26] ultrasonicactivation [27] solid protic acids [28ndash30] ionic liquids [31ndash33] and enzymes [34 35] However still in many of thesemethods use of excessive acetic anhydride application oftoxic metal containing catalysts and involvement of tediouswork-up conditions are required

In the framework of our studies to design ecofriendly syn-thetic procedures [36ndash39] and in continuation of our pro-gram to develop efficient procedures for functional groupsprotection [40ndash42] we recently reported an environmentallybenign chemoselective process for spontaneous acetylation ofvarious amines by acetic anhydride at room temperature byusing no catalyst or additive [43] However under the con-ditions thiols were acetylated in a much slower fashion andalcohols remained intact This persuaded us to search for analternative mild procedure under which alcohols and thiolscould also be acetylated efficiently As a result of our investiga-tionswe hereby report a novel protocol for rapid and selectiveacetylation of alcohols phenols and thiols under solvent-freeconditions by using only catalytic amounts of inexpensivesodium acetate trihydrate (NaOAcsdot3H

2O) (Scheme 1)

2 Results and Discussion

The isolated yields obtained for room-temperature acetyla-tion of selected alcohols and phenols in the presence of aceticanhydride and NaOAcsdot3H

2O are given in Table 1 Exper-

iments with several solvents showed that the best resultswould be obtained under solvent-free conditions When

2 Journal of Chemistry

Table 1 Room-temperature NaOAc catalyzed acetylation of alcohols and phenols

Entry Alcohol Product Time (min) Yield ()a

1 HO AcO 20 92

2 HO AcO 20 97

3HO AcO

15 96

4HO AcO

20 98

5HO AcO

10 91

6HO AcO

10 95

7HO

OMe OMe

AcO10 98

8HO AcO

10 96

9HO

Cl

AcO

Cl10 98

10HO

NO2

AcO

NO2

10 88

11HO O OAcO

10 88

12 HO AcO 20 91

13 HO

Ph Ph

AcO 10 96

14HO AcO

35 96

15HO AcO

15 96

16 HO AcO 20 94

17

HO AcO

70 90

Journal of Chemistry 3

Table 1 Continued


18HO AcO

55 91

19HO AcO

10 95

20 HO AcO 18 95

21HO Cl AcO Cl

10 98

22 HO AcO15 97

23 HO AcO 15 98

24OH OAc

20 98

25EtO

O

OH

EtO

O

OAc

25 97

26

COOH

OH OAc

COOH

10 98

aIsolated yield

Ac2O (11 equiv)

NaoAc3H2O (10moL)RndashXH RndashXAc

R = aryl and primary secondary and tertiary alkyls X = O S

Scheme 1 Ac2O catalyzed protection of alcohols and thiols

a solvent-free 10 10 01 mixture of 1-butanol acetic anhy-dride and NaOAcsdot3H

2O was stirred at room temperature

complete formation of butyl acetate was observed within 20minutes (entry 1) The 1H NMR and GC spectra of the reac-tion mixture showed the presence of butyl acetate as the soleproduct of the reaction The applicability of this method toother substrates was evaluated by using the same conditionsfor other primary (entries 2-3) propargylic (entry 4) allylic(entry 5) benzylic (entries 6ndash11) secondary (entries 12ndash16)

and tertiary (entries 17-18) alcohols In all cases rapid for-mation of the respective acetates was observed in high yieldswithin 10ndash70 minutes Further generality of this procedurewas demonstrated by convenient conversion of phenolswith different stereoelectronic nature to their correspondingacetates (entries 19ndash23) The methodology was also appliedfor efficient protection of the chiral alcohols menthol (entry24) and ethyl lactate (entry 25) while their chirality wasmaintained during the process Interestingly acetylsalicylicacid (aspirin) was easily prepared in high yields and purity byusing the conditions (entry 26) This could be a very impor-tant result from an industrial point of view since aspirin isnormally produced under very strong acidic conditions [4445] The development of the work in large-scale preparationof aspirin is under investigation

We next decided to use this chemistry for the pro-tection of thiols due to the importance of their masking


Table 2 Room-temperature NaOAc catalyzed acetylation of thiols

Entry RSH RSAc Time (min) Yield ()a

1 C6H5SH C6H5SAc 15 962 4-ClC6H4SH 4-ClC6H4SAc 30 903 2-naphthyl-SH 2-naphthyl-SAc 45 894 C6H5CH2SH C6H5CH2SAc 10 905 2-furyl-CH2SH 2-furyl-CH2SAc 25 92aIsolated yield

Table 3 Competitive acetylation of various functional groups with Ac2O

Entry Product 1 Product 2 1 2a

1 AcO AcO 95 5

2 AcO AcO 100 1

3 AcO AcO 70 30

4 AcO AcO Ph 20 80

5 AcO Ph AcOPh 10 90

6 AcSPh AcOPh 88 12

7 AcNHPh AcOPh 90 10

8 AcNHPh AcSPh 80 20

9 4-HO-C6H4-NHAc 4-AcO-C6H4-NH2 99 1aDetermined by GC

[15 47 48] in synthesis [1 2] biochemistry [49] and electro-chemistry [50 51] Therefore thiophenol 4-chlorothiophe-nol naphthalene-2-thiol phenylmethanethiol and furan-2-ylmethanethiol were conveniently acetylated in less than 1 hunder the conditions similar to those employed for alcohols(Table 2)

As previously noticed [43] alcohols and phenols reactwith acetic anhydride considerably slower than amines andthiols This phenomenon persuaded us to evaluate the feasi-bility of selective protection of hydroxyl groups in the pres-ence of competent functionalities The results shown inTable 3 clearly illustrate that primary alcohols are acetylatedin the presence of secondary (entry 1) or tertiary (entry 2)alcohols with very high selectively On the other hand com-petition between secondary and tertiary (entry 3) or primaryand benzylic (entry 4) hydroxyls results in preferential pro-tection of secondary or benzylic alcohols respectively These

results correlate with relative acidic strength of the alcoholsand are verified by preferential protection of phenol in thepresence of benzyl alcohol (entry 5) and thiophenol in thepresence of phenol (entry 6) However it seems that acidityis not a determining function when aromatic amines areinvolved As a result aniline is dominantly protected when itcompetes with phenol (entry 7) or with thiophenol (entry 8)Similarly intramolecular competition between NH

2and OH

groups in 4-aminophenol led to exclusive formation ofN-(4-hydroxyphenyl) acetamide (paracetamol) (entry 9) a widelyused over-the-counter analgesic drug [52] This difference inactivity might be attributed to higher nucleophilicity of theamine and spontaneous precipitation of the amide productThe difference in nucleophilicity is enhanced in the case of4-aminophenol (entry 9) where the amine group is furtheractivated by electron donating effects of the OH moietythrough resonance


Table 4 Comparison of the procedure with other related methods

Entry Conditions Time Reference1 NaOAc 10Min This work2 Polymer supported gadolinium triflateDMSO 15 h [19]3 Gadolinium triflateMeCN 30Min [16]4 A solid supported Co(II) salen complex50∘C 45Min [17]5 Carbon tetrabromide gt3 h [46]6 (Ru(acac)3) 5 h [13]

In conclusion we disclosed a very inexpensive andstraightforward procedure for catalytic conversion of variousalcohols and phenols to their respective acetyl products inhigh yields and short time periods High chemoselectivityand generality of the procedure lack of formation of sideproducts easy workup use of minimum quantities of Ac

2O

and the environmental safety of the reactions are among theadvantages of the present methodology Application of themethod in protection of carbohydrates is under investigationTo further highlight the efficiency of the present procedureTable 4 is provided to compare the results of NaOAc cat-alyzed acetylation of benzyl alcohol with some other recentlydeveloped methods It can easily be concluded from thiscomparison that the present reaction does not require hightemperature treatment or use of complicated reagents toproceed In addition the reaction takes place rapidly by usingno solvent

3 Experimental

31 General Remarks IR spectra were recorded using KBrdisks on a Bruker Vector-22 infrared spectrometer 1H NMRspectra were obtained on an FT-NMR Bruker Ultra Shield(500MHz) or Bruker AC 80MHz instrument as CDCl

3solu-

tions using TMS as the internal standard reference All chem-icals were purchased from commercial sources

32 General Procedure A solvent-free mixture of an alco-hol or thiol (10mmol) acetic anhydride (11mmol) andNaOAcsdot3H

2O (10mol) was stirred at room temperature for

appropriate length of time as indicated in Tables 1 and 2until TLC andor GC showed completion of the reactionThemixture was diluted by diethyl ether (10mL) andwashedwithsaturated solution of NaHCO

3 The organic layer was dried

over Na2SO4and concentrated under reduced pressure The

product was purified by column chromatography over silicagel using EtOAchexane eluant if necessary All productswere known and their identities were confirmed by compar-ing their spectral data with those available in the literature

Acknowledgment

The Analytical Department at the Chemistry and ChemicalEngineering Research Center of Iran is gratefully acknowl-edged for conducting the GC experiments

References

[1] P G M Wuts and T W Greene Greenersquos Protective Groups inOrganic Chemistry John Wiley and Sons Hoboken NJ USA4th edition 2007

[2] S Petursson ldquoDiarylmethyl ethers for the protection of polyolsrdquoJournal of Chemistry vol 2013 Article ID 183049 10 pages 2013

[3] A P Abbott T J Bell S Handa and B Stoddart ldquoO-Acetylationof cellulose and monosaccharides using a zinc based ionicliquidrdquo Green Chemistry vol 7 no 10 pp 705ndash707 2005

[4] M Adinolfi G Barone A Iadonisi and M Schiattarella ldquoAneasy approach for the acetylation of saccharidic alcohols Appli-cability for regioselective protectionsrdquo Tetrahedron Letters vol44 no 25 pp 4661ndash4663 2003

[5] Y Azeh G A Olatunji C Mohammed and P A MamzaldquoAcetylation of wood flour from four wood species grown innigeria using vinegar and acetic anhydriderdquo International Jour-nal of Carbohydrate Chemistry vol 2013 Article ID 141034 6pages 2013

[6] G Sartori R Ballini F Bigi G Bosica R Maggi and P RighildquoProtection (and deprotection) of functional groups in organicsynthesis by heterogeneous catalysisrdquo Chemical Reviews vol104 no 1 pp 199ndash250 2004

[7] D Habibi P Rahmani and Z Akbaripanah ldquoAcetylation ofphenols anilines and thiols using silica sulfuric acid undersolvent-free conditionsrdquo Journal of Chemistry vol 2013 ArticleID 268654 6 pages 2013

[8] Y V Subba Rao P Vijayanand S J Kulkarni M Subrah-manyam and A V Rama Rao ldquoShape selective deacetylationover zeolites a simple methodologyrdquo Synthetic Communica-tions vol 25 no 6 pp 849ndash855 1995

[9] V P Pathak ldquoA convenient method for O-deacetylation usingIRA-400(OH) resinrdquo Synthetic Communications vol 23 no 1pp 83ndash85 1993

[10] R C Larock Comprehensive Organic Transformations Wiley-VCH New York NY USA 2nd edition 1999

[11] R Shogren ldquoScandium triflate catalyzed acetylation of starch atlow to moderate temperaturesrdquo Carbohydrate Polymers vol 72no 3 pp 439ndash443 2008

[12] M D Carrigan D A Freiberg R C Smith HM Zerth and RS Mohan ldquoA simple and practical method for large-scale acety-lation of alcohols and diols using bismuth triflaterdquo Synthesis vol33 no 14 pp 2091ndash2094 2001

[13] R Varala A Nasreen and S R Adapa ldquoRuthenium(III) acety-lacetonate [Ru(acac)

3]mdashan efficient recyclable catalyst for the

acetylation of phenols alcohols and amines under neat condi-tionsrdquoCanadian Journal of Chemistry vol 85 no 2 pp 148ndash1522007


[14] A Kamal M N A Khan K S Reddy Y V V Srikanth and TKrishnaji ldquoAl(OTf)

3as a highly efficient catalyst for the rapid

acetylation of alcohols phenols and thiophenols under solvent-free conditionsrdquo Tetrahedron Letters vol 48 no 22 pp 3813ndash3818 2007

[15] J S Yadav A V Narsaiah A K Basak P R Goud D Sreenuand K Nagaiah ldquoNiobium pentachloride an efficient catalystfor the selective acetylation of amines and thiols under mildconditionsrdquo Journal of Molecular Catalysis A vol 255 no 1-2pp 78ndash80 2006

[16] R Alleti M Perambuduru S Samantha and V P Reddy ldquoGa-dolinium triflate an efficient and convenient catalyst for acety-lation of alcohols and aminesrdquo Journal of Molecular Catalysis Avol 226 no 1 pp 57ndash59 2005

[17] F Rajabi ldquoA heterogeneous cobalt(II) Salen complex as anefficient and reusable catalyst for acetylation of alcohols andphenolsrdquo Tetrahedron Letters vol 50 no 4 pp 395ndash397 2009

[18] S Farhadi andM Zaidi ldquoBismuth ferrite (BiFeO3) nanopowder

prepared by sucrose-assisted combustion method a noveland reusable heterogeneous catalyst for acetylation of aminesalcohols and phenols under solvent-free conditionsrdquo Journal ofMolecular Catalysis A vol 299 no 1-2 pp 18ndash25 2009

[19] H J Yoon S M Lee J H Kim et al ldquoPolymer-supportedgadolinium triflate as a convenient and efficient Lewis acid cata-lyst for acetylation of alcohols and phenolsrdquoTetrahedron Lettersvol 49 no 19 pp 3165ndash3171 2008

[20] J K Joseph S L Jain and B Sain ldquoAlumina supported MoO3as a highly efficient and recyclable heterogeneous catalyst forthe chemoselective acetylation of alcohols phenols amines andthiols with acetic anhydride under solvent free conditionsrdquoJournal of Molecular Catalysis A vol 267 no 1-2 pp 108ndash1112007

[21] B Das PThirupathi R A Kumar andK Laxminarayana ldquoPart148 in the series ldquostudies on novel synthetic methodologiesrdquoselective acetylation of alcohols phenols and amines and selec-tive deprotection of aromatic acetates using silica-supportedphosphomolybdic acidrdquo Advanced Synthesis and Catalysis vol349 no 17-18 pp 2677ndash2683 2007

[22] B Das and PThirupathi ldquoA highly selective and efficient acety-lation of alcohols and amines with acetic anhydride usingNaHSO

4sdotSiO2as a heterogeneous catalystrdquo Journal of Molecular

Catalysis A vol 269 no 1-2 pp 12ndash16 2007[23] M M Sa and L Meier ldquoPyridine-free and solvent-free acetyla-

tion of nucleosides promoted by molecular sievesrdquo Synlett vol17 no 20 pp 3474ndash3478 2006

[24] J Mack and S Muthukrishnan ldquoSolvent-free synthesisrdquo inGreen Techniques for Organic Synthesis and Medicinal Chem-istry W Zhang and B W Cue Eds pp 297ndash324 John Wileyand Sons Chichester UK 20132012

[25] S K Das K A Reddy V L N R Krovvidi and K MukkantildquoInCl

3as a powerful catalyst for the acetylation of carbohydrate

alcohols under microwave irradiationrdquo Carbohydrate Researchvol 340 no 7 pp 1387ndash1392 2005

[26] B P Bandgar S P Kasture and V T Kamble ldquoChemoselectiveacetylation of alcohols amines and thiols without catalyst andsolventrdquo Synthetic Communications vol 31 no 15 pp 2255ndash2259 2001

[27] A R Gholap K Venkatesan T Daniel R J Lahoti and KV Srinivasan ldquoUltrasound promoted acetylation of alcohols inroom temperature ionic liquid under ambient conditionsrdquoGreen Chemistry vol 5 no 6 pp 693ndash696 2003

[28] S T Kadam and S K Sung ldquoPhosphomolybdic acid mild andefficient catalyst for acetylation of alcohols phenols and aminesunder solvent-free conditionsrdquo Synthesis vol 40 no 2 pp 267ndash271 2008

[29] M M Heravi K Bakhtiari N M Javadi H A Oskooie and FF Bamoharram ldquoSelective acetylation of alcohols and amineswith ethyl acetate in the presence of H

6[PMo

9V3O40] as the

catalystrdquo Monatshefte fur Chemie vol 138 no 5 pp 445ndash4472007

[30] R H Tale and R N Adude ldquoA novel 3-nitrobenzeneboronicacid as an extremely mild and environmentally benign catalystfor the acetylation of alcohols under solvent-free conditionsrdquoTetrahedron Letters vol 47 no 40 pp 7263ndash7265 2006

[31] W Wang W Cheng L Shao and J Yang ldquo[TMBSA][HSO4]ionic liquid as novel catalyst for the rapid acetylation of alco-hols hydroxyesters and phenols under solvent-free conditionsrdquoCatalysis Letters vol 121 no 1-2 pp 77ndash80 2008

[32] Y Liu L Liu Y Lu and Y Q Cai ldquoAn imidazolium tosylatesalt as efficient and recyclable catalyst for acetylation in an ionicliquidrdquo Monatshefte fur Chemie vol 139 no 6 pp 633ndash6382008

[33] R Alleti S O Woon M Perambuduru Z Afrasiabi E Sinnand V P Reddy ldquoGadolinium triflate immobilized in imida-zolium based ionic liquids a recyclable catalyst and green sol-vent for acetylation of alcohols and aminesrdquo Green Chemistryvol 7 no 4 pp 203ndash206 2005

[34] L L Machado T L G Lemos M C de Mattos et al ldquoImmobi-lizedManihot esculenta preparation as a novel biocatalyst in theenantioselective acetylation of racemic alcoholsrdquo TetrahedronAsymmetry vol 19 no 12 pp 1418ndash1423 2008

[35] F Benfatti G Cardillo L Gentilucci E Mosconi and ATolomelli ldquoEnzymatic resolution of ethyl 3-hydroxy-2(11015840sub-stituted-methylidene)-butyrate by Pseudomonas cepacia lipasecatalyzed acetylationrdquo Tetrahedron Asymmetry vol 18 no 18pp 2227ndash2232 2007

[36] M M Mojtahedi E Akbarzadeh R Sharifi and M S AbaeeldquoLithium bromide as a flexible mild and recyclable reagent forsolvent-free cannizzaro tishchenko and meerwein-ponndorf-verley reactionsrdquo Organic Letters vol 9 no 15 pp 2791ndash27932007

[37] M S Abaee VHamidi andMMMojtahedi ldquoUltrasound pro-moted aminolysis of epoxides in aqueous media a rapid pro-cedure with no pH adjustment for additive-free synthesis of120573-aminoalcoholsrdquo Ultrasonics Sonochemistry vol 15 no 5 pp823ndash827 2008

[38] M M Mojtahedi M S Abaee and T Alishiri ldquoSuperparamag-netic iron oxide as an efficient catalyst for the one-pot solvent-free synthesis of 120572-aminonitrilesrdquo Tetrahedron Letters vol 50no 20 pp 2322ndash2325 2009

[39] M M Mojtahedi M S Abaee and H Abbasi ldquoOne-pot sol-vent-free synthesis of 120572-aminonitriles under catalysis by mag-nesium bromide ethyl etheraterdquoCanadian Journal of Chemistryvol 84 no 3 pp 429ndash432 2006

[40] M M Mojtahedi M Saeed Abaee V Hamidi and A Zolfa-ghari ldquoUltrasound promoted protection of alcohols an efficientsolvent-free pathway for the preparation of silyl ethers in thepresence of no additiverdquo Ultrasonics Sonochemistry vol 14 no5 pp 596ndash598 2007

[41] M M Mojtahedi M S Abaee and M Eghtedari ldquoSuperpara-magnetic iron oxide as an efficient and recoverable catalystfor rapid and selective trimethylsilyl protection of hydroxyl


groupsrdquo Applied Organometallic Chemistry vol 22 no 9 pp529ndash532 2008

[42] M M Mojtahedi H Abbasi and M S Abaee ldquoMgBr2sdotOEt2

mediated protection of alcohols with hexamethyldisilazane anefficient catalytic route for the preparation of silyl ethers undersolvent-free conditionsrdquo Journal of Molecular Catalysis A vol250 no 1-2 pp 6ndash8 2006

[43] M M Mojtahedi M Saeed Abaee M M Heravi and F KBehbahani ldquoAdditive-free chemoselective acylation of aminesand thiolsrdquo Monatshefte fur Chemie vol 138 no 1 pp 95ndash992007

[44] K D Rainsford Aspirin and Related Drugs Taylor and FrancisLondon UK 2004

[45] J F Neault A Novetta-Delen H Arakawa H Malonga and HA Tajmir-Riahi ldquoThe effect of aspirin-HSA complexation onthe protein secondary structurerdquo Canadian Journal of Chem-istry vol 78 no 2 pp 291ndash296 2000

[46] L Zhang Y Luo R Fan and J Wu ldquoMetal- and solvent-freeconditions for the acylation reaction catalyzed by carbon tetra-bromide (CBr

4)rdquo Green Chemistry vol 9 no 9 pp 1022ndash1025

2007[47] A T Khan S Islam A Majee T Chattopadhyay and S Ghosh

ldquoBromodimethylsulfonium bromide a useful reagent for acy-lation of alcohols phenols amines thiols thiophenols and 11-diacylation of aldehydes under solvent free conditionsrdquo Journalof Molecular Catalysis A vol 239 no 1-2 pp 158ndash165 2005

[48] S P Chavan R Anand K Pasupathy and B S Rao ldquoCatalyticacetylation of alcohols phenols thiols and amines with zeoliteH-FER under solventless conditionsrdquo Green Chemistry vol 3no 6 pp 320ndash322 2001

[49] T Suzuki A Kouketsu A Matsuura et al ldquoThiol-based SAHAanalogues as potent histone deacetylase inhibitorsrdquo Bioorganicand Medicinal Chemistry Letters vol 14 no 12 pp 3313ndash33172004

[50] N Stuhr-Hansen J B Christensen N Harrit and TBjoslashrnholm ldquoNovel synthesis of protected thiol end-cappedstilbenes and oligo(phenylenevinylene)s (OPVs)rdquo Journal ofOrganic Chemistry vol 68 no 4 pp 1275ndash1282 2003

[51] O P H Vaughan M Turner F J Williams A Hille J K MSanders and R M Lambert ldquoDirect observation of surface-mediated thioacetyl deprotection covalent tethering of a thiol-terminated porphyrin to the Ag(100) surfacerdquo Journal of theAmerican Chemical Society vol 128 no 30 pp 9578ndash95792006

[52] AKleemann J Engel B Kutscher andDReichertPharmaceu-tical Substances GeorgThieme Stutgart Germany 4th edition2001

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Bioinorganic Chemistry and ApplicationsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

SpectroscopyInternational Journal of


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Applied ChemistryJournal of



Theoretical ChemistryJournal of


Journal of

Spectroscopy

Analytical ChemistryInternational Journal of


Journal of


Quantum Chemistry


Organic Chemistry International

ElectrochemistryInternational Journal of



CatalystsJournal of


Table 1 Room-temperature NaOAc catalyzed acetylation of alcohols and phenols


1 HO AcO 20 92

2 HO AcO 20 97

3HO AcO

15 96

4HO AcO

20 98

5HO AcO

10 91

6HO AcO

10 95

7HO

OMe OMe

AcO10 98

8HO AcO

10 96

9HO

Cl

AcO

Cl10 98

10HO

NO2

AcO

NO2

10 88

11HO O OAcO

10 88

12 HO AcO 20 91

13 HO

Ph Ph

AcO 10 96

14HO AcO

35 96

15HO AcO

15 96

16 HO AcO 20 94

17

HO AcO

70 90


Table 1 Continued


18HO AcO

55 91

19HO AcO

10 95

20 HO AcO 18 95

21HO Cl AcO Cl

10 98

22 HO AcO15 97

23 HO AcO 15 98

24OH OAc

20 98

25EtO

O

OH

EtO

O

OAc

25 97

26

COOH

OH OAc

COOH

10 98

aIsolated yield

Ac2O (11 equiv)















1 AcO AcO 95 5

2 AcO AcO 100 1

3 AcO AcO 70 30

4 AcO AcO Ph 20 80


6 AcSPh AcOPh 88 12







2and OH






2O


3 Experimental


3solu-








Acknowledgment


References








































6[PMo

9V3O40] as the







































Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


Table 1 Continued


18HO AcO

55 91

19HO AcO

10 95

20 HO AcO 18 95

21HO Cl AcO Cl

10 98

22 HO AcO15 97

23 HO AcO 15 98

24OH OAc

20 98

25EtO

O

OH

EtO

O

OAc

25 97

26

COOH

OH OAc

COOH

10 98

aIsolated yield

Ac2O (11 equiv)















1 AcO AcO 95 5

2 AcO AcO 100 1

3 AcO AcO 70 30

4 AcO AcO Ph 20 80


6 AcSPh AcOPh 88 12







2and OH






2O


3 Experimental


3solu-








Acknowledgment


References








































6[PMo

9V3O40] as the







































Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of







1 AcO AcO 95 5

2 AcO AcO 100 1

3 AcO AcO 70 30

4 AcO AcO Ph 20 80


6 AcSPh AcOPh 88 12







2and OH






2O


3 Experimental


3solu-








Acknowledgment


References








































6[PMo

9V3O40] as the







































Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of





2O


3 Experimental


3solu-








Acknowledgment


References








































6[PMo

9V3O40] as the







































Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of

























6[PMo

9V3O40] as the







































Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of

research article efficient and rapid solvent-free...

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