Substituent effect on the enantioselectivity in lipase-catalyzed transesterification of trans-2,5-disubstituted pyrrolidines

Kinetic resolutions of N-substituted benzyl-trans-2-acetoxymethyl-5-(hydrox ymethyl)pyrrolidines using lipase-catalyzed trans-esterification have been systematically studied. The enantioselectivity depends significantly on the position of substituent at the aromatic ring and N-3,5-dimethylbenzyl grou p was found to transform trans-2,5-disubstituted pyrrolidine derivative int o an efficiently-resolved substrate. Furthermore, the enantioselectivity co uld be improved up to E=108 using the immobilized Lipase in alkyl silica ge l. (C) 2001 Elsevier Science Ltd. AU rights reserved.