Selective lipase‐catalyzed 6‐O‐acylation of alkyl α‐D‐glucopyranosides using functionalized ethyl esters

Alkyl α‐D‐glucopyranosides were selectively converted into their 6‐O‐acyl esters by lipase‐catalyzed transesterification with ethyl acrylate or ethyl 4‐chlorobutanoate. Comparison of six lipase preparations showed large differences in activity and selectivity. The addition of zeolite CaA for selective adsorption of ethanol and water, exerted profound effects on conversion and regioselectivity of the transesterification. A quantitative conversion with high selectivity was achieved using lipases from C. antarctica in the presence of zeolite CaA.