Chiral crown complexes catalyse Michael addition reactions to give adducts in high optical yields

Abstract
Chiral crowns complexed to potassium bases catalyse with high turnover numbers the Michael additions of a β-ketoester to methyl vinyl ketone, and of two phenylacetic esters to methyl acrylate, to give products of 99–60% optical purity with a configurational bias rationalizable on the basis of steric effects.