Resolution of the diols of bicyclo[2.2.1]heptane, bicyclo[2.2.2]octane and bicyclo[3.2.1]octane by enzymic hydrolysis, and their absolute configurations

Abstract

Enzyme (pig liver esterase and lipase from Aspergillus niger)-catalysed enantioselective hydrolyses of racemic diacetates, (1R*,2S*,4R*,5S*)- and (1R*,2R*,4R*,5R*)-2,5-diacetoxybicyclo[2.2.1]heptanes, (1R*,2S*,4R*,5S*)-, (1R*,2R*,4R*,5R*)- and (1R*,2R*,4R*,5S*)-2,5-diacetoxybicyclo[2.2.2]-octanes, (2R*,3R*)-2,3-diacetoxybicyclo[2.2.2]octane and (1R*,2S*,6S*,8R*)- and (1R*,2S*,6S*,8S*)-2,8-diacetoxybicyclo[3.2.1]octanes gave the corresponding monoacetates and the recovered diacetates in an optically active form. The absolute configurations of products were unequivocally determined by chemical correlation to the corresponding known monoacetates, (2S)-(+)-2-acetoxybicyclo[2.2.1]heptane, (2S)-(+)-2-acetoxybicyclo[2.2.2]octane and (2S)-(+)-2-acetoxybicyclo[3.2.1 ]octane, and circular dichroism spectra of keto acetates and diketones derived from the hydrolysis products were examined.