HIGHLY ENANTIOSELECTIVE OPENING OF CYCLIC MESO-ANHYDRIDES TO ISOPROPYL HEMIESTERS WITH DIISOPROPOXYTITANIUM TADDOLATES

The Lewis acid mediated transfer of an alkoxide ligand from the chiral ligand sphere of 1 facilitates the highly enantioselective ring‐opening of cyclic CS‐symmetric anhydrides 2 to the corresponding hemiesters 3 with enantiomer ratios up to 99:1. This ability to transfer ligands could make 1 an organometallic alternative to hydrolytic enzymes, as the differntiation of enantiotopic functional groups in meso compounds and the resolution of racemic substrates should be possible. (Figure Presented.) Copyright © 1995 by VCH Verlagsgesellschaft mbH, Germany