Organocatalytic Asymmetric Tandem Conjugate Addition–Protonation of Azlactones to N-Itaconimides

Abstract

An unprecedented catalytic asymmetric reaction between azlactones and N-itaconimides has been developed. In the presence of an l-tert-leucine-based urea–tertiary amine Brønsted base catalyst, the tandem conjugate addition–protonation products could be attained in moderate yields with excellent enantio- and diastereoselectivities (up to 99% ee and >20:1 dr). The method provides an efficient approach to access valuable chiral γ-tertiary amine substituted succinimides containing nonadjacent stereocenters.