Selective Acetylation of the Primary Hydroxyl Group in Methyl D-Hexopyranosides with a Mixture of Acetic Anhydride and Acetic Acid

Abstract

6-O-Acetylated derivatives of D-hexopyranosides are valuable intermediates in synthetic carbohydrate chemistry. We have developed a new simple procedure for selective acetylation of the primary hydroxyl group in methyl D-hexopyranosides consisting in treatment with a mixture of acetic anhydride and acetic acid at 50°C. As a result, corresponding 6-acetates were formed in 40–50% yield.