The Pyrrolidine‐Catalyzed Three‐Component Reactions of Azlactones,N,O‐Acetals and Alcohols: One‐Pot Synthesis of α,β‐Diamino Esters

Abstract

A pyrrolidine‐catalyzed three‐component reaction of azlactone, N,O‐acetal and alcohol for the synthesis of α,β‐diamino ester was reported. The N,O‐acetal served as the imine equivalent to occur Mannich reaction with azlactone, and the in situ generated α‐functionalized azlactone subsequently underwent a ring‐opening process in the presence of alcohol. A series of α,β‐diamino esters were obtained in 36–99% yields under mild reaction conditions. The product could be synthesized on gram‐scale and transformed into the α,β‐diamino acid.