Highly enantio- and diastereoselective organocatalytic cascade aza-Michael-Michael reactions: A direct method for the synthesis of trisubstituted chiral pyrrolidines

An unprecedented highly enantio- and diastereoselective cascade aza-Michael-Michael reaction of α,β-unsaturated aldehydes with trans-γ-Ts protected amino α,β-unsaturated ester has been developed; the simple and practical process, efficiently catalyzed by chiral diphenylprolinol TMS ether, serves as a powerful access to highly functionalized trisubstituted chiral pyrrolidines.