Highly enantioselective Michael addition reactions of 2-substituted benzofuran-3(2H)-ones to nitroolefins

Abstract

A highly enantioselective Michael addition reaction of 2-substituted benzofuran-3(2H)-ones to nitroolefins was promoted by a bifunctional squaramide catalyst. As a result, a number of chiral 2,2′-substituted benzofuran-3-one derivatives, bearing adjacent quaternary–tertiary stereocenters, were efficiently synthesized with excellent enantioselectivities.