Asymmetric Bio- and Chemoreduction of 2-Benzylidenecyclopentanone Derivatives

Abstract

Highly efficient asymmetric reduction of 2-benzylidenecyclopentanone derivatives to give the respective exocyclic allylic alcohols in ee's up to 96% was performed with chiral oxazaborolidine-based catalysts. Complete enantioselectivity furnishing (S)-configured alcohol product could be achieved by bioreduction of 2-(4-chlorobenzylidene)cyclopentanone with Daucus carota root. The synthesized compounds may be used as enantiomerically enriched standards for the monitoring of the enzyme-catalyzed redox processes.