Trinuclear tin salicylaldoximate cluster‐catalyzed selective acylation of alcohols

Abstract

The reactivity and catalytic potential of the tin salicylaldoximate cluster [(Me 2 Sn) 2 (Me 2 SnO)(OCH 3 ) (HONZO)(ONZO)] (1), with HONZOH = o-HON CH-C 6 H 4 OH, on the acylation reaction of various alcohols with ethyl acetate is reported. The catalyst is active toward primary and unhindered secondary alcohols, but inefficient toward tertiary and secondary bulky alcohols and phenols. A possible mechanism for the transesterification reaction catalyzed by 1, accounting for the influence of steric factors, is proposed.

An Efficient and Facile Procedure for Synthesis of Acetates from Alcohols Catalyzed by Poly(4-vinylpyridinium tribromide)

“…Acylation of alcohols has enjoyed numerous applications in synthetic organic chemistry, pharmaceutical chemistry, and industrial applications [2,3]. In addition, the protection of the hydroxyl group as acetate is preferred due to its ease of introduction, ease of hydrolysis by mild alkaline reagents [4], and also because it protects the OH functionality during oxidation, coupling, and glycosidation reactions [5].…”

“…-yl)-2,3,4,7,8,9,10,11,12,13,14,15,16,17tetradecahydro-1H-cyclopenta[a]phenanthren-3-yl acetate (2n).1 H-NMR (CDCl 3 , 400 MHz): δ 0.71(s, 3H), 0.89 (d, J = 6.8 Hz, 6H), 0.95 (d, J = 6.4 Hz, 4H), 1.07 (s, 4H), 1.15 (m, 7H), 1.38 (m, 4H), 1.55 (m, 8H), 1.8-1.97 (m, 3H), 1.94-1.98 (s, 1H), 2.05 (s, 3H), 2.34 (d. J = 7.2 Hz, 2H), 4.63 (m, J = 5.2 Hz, 2H), 5.398 (d, J = 4.4 Hz, 1H); 13 C-NMR (CDCl 3 , 100 MHz): δ 11.8, 18.7, 19.3, 21, 21.4,…”