Novel enzymatic route for kinetic resolution of (±)1,4-benzodioxan-2-carboxylic acid

Abstract

Ethyl 1,4-benzodioxan-2-carboxylate is used as an intermediate compound for the production of drug doxazosin mesylate. The title compound was kinetically resolved to get S-enantiomer of ethyl 1,4-benzodioxan 2-carboxylate in a simple lipase catalyzed transesterification reaction. Ethyl acetate was used as reaction medium as well as acyl donor. The influence of the enzyme source and time of reaction on the enantio selectivity of product were studied. Lipase from Candida antartica-B (Novozyme A/S) catalyzed transesterification reaction with good enantio selectivity towards S-enantiomer. The high enantiomeric ratio, E = 160, provided S -2 an acceptable chemical yield (50%) and enantiomeric excess (>95%).