Organosilicon-mediated regioselective acetylation of carbohydrates
Yixuan Zhou1, Olof Ramström, Hai Dong
1Huazhong University of Science & Technology, School of Chemistry & Chemical Engineering, Luoyu Road 1037, 430074 Hongshan, Wuhan, PR China.
Abstract:
Organosilicon-mediated, regioselective acetylation of vicinal- and 1,3-diols is presented. Methyl trimethoxysilane or dimethyl dimethoxysilane was first used to form cyclic 1,3,2-dioxasilolane or 1,3,2-dioxasilinane intermediates, and subsequent acetate-catalyzed monoacylation was efficiently performed by addition of acetic anhydride or acetyl chloride under mild conditions. The reaction exhibited high regioselectivity, resulting in the same protection pattern as in organotin-mediated schemes.
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