Two‐step chemo‐enzymatic synthesis of octyl 6‐<i>O</i>‐acyl‐α‐D‐glucopyranoside surfactants from glucose

Abstract

Abstract Three novel carbohydrate surfactants were synthesized by lipase‐catalyzed transesterification of octyl 2‐D‐glucopyranoside, obtained from the acid‐catalyzed reaction of glucose and octanol. The 6‐OH was regioselectively acylated with ethyl octanoate, ethyl acetoacetate and diethyl succinate as acyl‐donating agents. Several lipases have been investigated as biocatalysts. For each esterification, various combinations of lipase, ester and cosolvent were studied, from which a preparative‐scale synthesis was developed. The new compounds were tested for physical properties (melting behaviour, surface tension and CMC): it appears that all 6‐acyl derivatives have surfactant characteristics. The 6‐octanoyl derivative was also found to have liquid‐crystal properties.