Catalytic Enantioselective 1,3‐Dipolar Cycloaddition Reaction of Azomethine Ylides and Alkenes: The Direct Strategy To Prepare Enantioenriched Highly Substituted Proline Derivatives

Abstract

A direct hit! The asymmetric 1,3-dipolar cycloaddition of azomethine ylides (from imines A; EWG=electron-withdrawing group) and electrophilic alkenes B using chiral metal complexes in substoichiometric amounts provides a direct stereoselective synthesis of pyrrolidine or proline derivatives. The successful ligand/metal cation couples are rationalized on the basis of recently published results.