Enantioselective Michael addition catalyzed by chiral tripodal oxazoline-tBuOK complexes

Benzene-based tripodal oxazolines are found to be novel chiral ligands for the catalytic enantioselective Michael addition via potassium enolates. Thus, methyl phenylacetate undergoes 1,4-addition to methyl acrylate using a catalytic amount of a tBuOK-oxazoline complex in toluene at -78 degreesC, and up to 82% ee is obtained. (C) 2001 Elsevier Science Ltd. All rights reserved.