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Chemoselective Acetylation of Alcohols
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(9) (a) Ohshima, T.; Iwasaki, T.; Mashima, K. Chem. Commun.
2006, 2711. (b) Ohshima, T.; Iwasaki, T.; Maegawa, Y.;
Yoshiyama, A.; Mashima, K. J. Am. Chem. Soc. 2008, 130,
2944. (c) Iwasaki, T.; Maegawa, Y.; Hayashi, Y.; Ohshima,
T.; Mashima, K. J. Org. Chem. 2008, 73, 5147. (d) Sniady,
A.; Durham, A.; Morreale, M. S.; Marcinek, A.; Szafert, S.;
Lis, T.; Brzezinska, K. R.; Iwasaki, T.; Ohshima, T.;
Mashima, K.; Dembinski, R. J. Org. Chem. 2008, 73, 5881.
(10) (a) Burley, S. K.; David, P. R.; Taylor, A.; Lipscomb, W. N.
Proc. Natl. Acad. Sci. U.S.A. 1990, 87, 6878. (b) Roderick,
S. L.; Matthews, B. W. Biochemistry 1993, 32, 3907.
(c) Chevrier, B.; Schalk, C.; D’orchymont, H.; Rondeau, J.
M.; Moras, D.; Tarnus, C. Structure (Cambridge, MA, U.S.)
1994, 2, 283. (d) Leopoldini, M.; Russo, N.; Toscano, M.
J. Am. Chem. Soc. 2007, 129, 7776.
(11) For a general review, see: (a) Multimetallic Catalysts in
Organic Synthesis; Shibasaki, M.; Yamamoto, Y., Eds.;
Wiley-VCH: Weinheim, 2004. For representative examples
of multinuclear zinc catalysts, see: (b) Yoshikawa, N.;
Kumagai, N.; Matsunaga, S.; Moll, G.; Ohshima, T.; Suzuki,
T.; Shibasaki, M. J. Am. Chem. Soc. 2001, 123, 2466.
(c) Trost, B. M.; Ito, H.; Silcoff, E. R. J. Am. Chem. Soc.
2001, 123, 3367.
References and Notes
(1) (a) Comprehensive Organic Synthesis, Vol 6.; Trost, B. M.;
Fleming, I., Eds.; Pergamon Press: New York, 1992.
(b) Larock, R. C. In Comprehensive Organic
Transformations, 2nd ed.; Wiley-VCH: New York, 1996.
(c) Otera, J. In Esterification Methods, Reactions and
Applications; Wiley-VCH: Weinheim, 2003.
(2) Protective Groups in Organic Synthesis, 4th ed.; Green,
T. W.; Wuts, P. G. M., Eds.; John Wiley and Sons: New
Jersey, 2006.
(3) For a representative example of catalytic acetylation with
Ac2O under auxiliary base-free conditions, see: Sakakura,
A.; Kawajiri, K.; Ohkubo, T.; Kosugi, Y.; Ishihara, K. J. Am.
Chem. Soc. 2007, 129, 14775; and references therein.
(4) For reviews, see: (a) Otera, J. Chem. Rev. 1993, 93, 1449.
(b) Hydonckx, H. E.; De Vos, D. E.; Chavan, S. A.; Jacobs,
P. A. Top. Catal. 2004, 27, 83. (c) Grasa, G. A.; Singh, R.;
Nolan, S. P. Synthesis 2004, 971.
(5) For acetylation using enol esters as an acyl donor, see:
(a) Kita, Y.; Maeda, H.; Omori, K.; Okuno, T.; Tamura, Y.
Synlett 1993, 273. (b) Ishii, Y.; Takeno, M.; Kwasaki, Y.;
Murromachi, A.; Nishiyama, Y.; Sakaguchi, S. J. Org.
Chem. 1996, 61, 3088. (c) Dinh, P. M.; Howarth, J. A.;
Hudnott, A. R.; Williams, J. M. J. Tetrahedron Lett. 1996,
37, 7623. (d) Orita, A.; Mitsutome, A.; Otera, J. J. Org.
Chem. 1998, 63, 2420. (e) Ilankumaran, P.; Verkade, J. G.
J. Org. Chem. 1999, 64, 9063. (f) Lin, M.-H.; RajanBabu,
T. V. Org. Lett. 2000, 2, 997. (g) Grasa, G. A.; Kissling, R.
M.; Nolan, S. P. Org. Lett. 2002, 4, 3583. (h) Grasa, G. A.;
Güveli, T.; Singh, R.; Nolan, S. P. J. Org. Chem. 2003, 68,
2812. (i) Bosco, J. W. J.; Saikia, A. K. Chem. Commun.
2004, 1116. (j) Shirae, Y.; Mino, T.; Hasegawa, T.;
Sakamoto, M.; Fujita, T. Tetrahedron Lett. 2005, 46, 5877.
(k) Bosco, J. W. J.; Agrahari, A.; Saikia, A. K. Tetrahedron
Lett. 2006, 47, 4065. (l) Kobayashi, J.; Mori, Y.; Kobayashi,
S. Chem. Commun. 2006, 4227. (m) Mino, T.; Hasegawa,
T.; Shirae, Y.; Sakamoto, M.; Fujita, T. J. Organomet.
Chem. 2007, 692, 4389. (n) Magen, S.; Ertelt, M.; Jatsch,
A.; Plietker, B. Org. Lett. 2008, 10, 53.
(6) For acetylation with enol esters by enzymes, see: (a) Wong,
C.-H.; Whitesides, G. M. In Enzymes in Synthetic Organic
Chemistry; Pergamon: Oxford, 1994. (b) Faber, K. In
Biotransformations in Organic Chemistry; Spinger: Berlin,
2000.
(7) (a) Nishiguchi, T.; Taya, H. J. Am. Chem. Soc. 1989, 111,
9102. (b) Iranpoor, N.; Shekarriz, M. Bull. Chem. Soc. Jpn.
1999, 72, 455. (c) Orita, A.; Sakamoto, K.; Hamada, Y.;
Mitsutome, A.; Otera, J. Tetrahedron 1999, 55, 2899.
(d) Ranu, B. C.; Dutta, P.; Sarkar, A. J. Chem. Soc., Perkin
Trans. 1 2000, 2223. (e) Habibi, M. H.; Tangestaninejad, S.;
Mirkhani, V.; Yadollahi, B. Tetrahedron 2001, 57, 8333.
(f) Singh, R.; Kissling, R. M.; Letellier, M.-A.; Nolan, S. P.
J. Org. Chem. 2004, 69, 209. (g) Tayebee, R.; Alizadeh,
M. H. Monatsh. Chem. 2006, 137, 1063.
(12) See Supporting Information for details.
(13) Otera, J. Acc. Chem. Res. 2004, 37, 288.
(14) In a similar way, acidic alcohols, such as 1,1,1,3,3,3-
hexafluoropropan-2-ol (pKa 9.3), did not participate in the
acylation, see ref. 9c.
(15) For primary aliphatic alcohol selective acetylation by
catalytic transesterification, see ref. 5d,f,i,k,7d,g.
(16) For a review, see: Nahmany, M.; Melman, A. Org. Biomol.
Chem. 2004, 2, 1563.
(17) (a) Mukaiyama, T.; Pai, F.-C.; Onaka, M.; Narasaka, K.
Chem. Lett. 1980, 563. (b) Brown, B. R.; Cocker, J.
J. Chem. Res., Synop. 1984, 2, 46. (c) Gardossi, L.;Bianchi,
D.; Kibanov, A. M. J. Am. Chem. Soc. 1991, 113, 6328.
(18) Yield of 9 was determined after N-Boc protection to simplify
the analysis.
(19) Typical Experimental Procedure for the Acetylation of
Alcohol 2f
A mixture of Zn4 (OCOCF3)6O (1, 36 mg, 0.038 mmol),
4-(triethylsiloxymethyl)benzyl alcohol (2f, 759 mg, 3.0
mmol), and EtOAc (5.0 mL) was refluxed for 18 h under an
argon atmosphere. The resulting mixture was concentrated
and purified by silica gel column chromatography (silica gel,
hexane–EtOAc = 20:1 to 4:1) to provide the acetate 3f (790
mg, 89%) as a colorless oil together with unreacted substrate
2f (38 mg, 5%). IR (neat NaCl): 2955, 2876, 1744, 1517,
1458, 1415, 1379, 1362, 1228, 1092, 1019, 971, 820, 742
cm–1. 1H NMR (300 MHz, CDCl3, 35 °C): d = 0.65 (q,
J = 7.5 Hz, 6 H, SiCH2CH3), 0.98 (t, J = 7.5 Hz, 9 H,
SiCH2CH3), 2.08 (s, 3 H, COCH3), 4.73 (s, 2 H, ArCH2OSi),
5.09 (s, 2 H, ArCH2OAc), 7.32 (m, 4 H, Ar). 13C NMR (75
MHz, CDCl3, 35 °C): d = 4.51, 6.70, 20.92, 64.39, 66.13,
126.32, 128.21, 134.62, 141.54, 170.76. MS (EI): m/z
(%) = 294 (1) [M+], 265 (62), 145 (100), 103 (39), 75 (20).
HRMS (EI): m/z calcd for C16H26O3Si: 294.1651; found:
294.1646.
(8) Substrates bearing cyclic acetal and TBDMS ether
functionalities were used for In/I2 catalyst system, see ref.
7d. Representative examples using stoichiometric amounts
of reagents, see: (a) Posner, G. H.; Oda, M. Tetrahedron
Lett. 1981, 22, 5003. (b) Posner, G. H.; Okada, S. S.;
Babiak, K. A.; Miura, K.; Rose, R. K. Synthesis 1981, 789.
Synlett 2009, No. 10, 1659–1663 © Thieme Stuttgart · New York