Lipase‐Catalysed Enzymatic Kinetic Resolution of Aromatic Morita‐Baylis‐Hillman Derivatives by Hydrolysis and Transesterification

Abstract

Acylated Morita-Baylis-Hillman (MBH) adducts were synthesised and subjected to enzymatic kinetic resolution (EKR) by hydrolysis employing various lipase enzymes: from P. fluorescens, P. cepacia (PCL), C. antarctica A (CALÀ A), C. antarctica B (CALÀ B) and Novozyme 435. In a number of instances enantiopure Morita-Baylis-Hillman acetates or butyrates and their corresponding hydrolysed MBH adducts were obtained with ee values of > 90 %, at ca. 50 % conversion, corresponding to enantiomeric ratio (E) values of > 200. Enantioselective transesterification reactions on MBH adducts was achieved using acyl anhydrides in THF or the greener organic solvent 2-MeTHF in the presence of CALÀ A. This is the first report of successful lipase-catalysed EKR of aromatic MBH adducts by transesterification in organic medium.