Asymmetric synthesis of beta-amino esters by aza-Michael reaction of alpha,beta-unsaturated amides using (S,S)-(+)-pseudoephedrine as chiral auxiliary.
Chiral nonracemic beta-amino esters were prepared in good yields and enantioselectivities using the diastereoselective conjugate addition of nitrogen nucleophiles to alpha,beta-unsaturated amides derived from (S,S)-(+)-pseudoephedrine as the key step. In this way, several beta-amino amide adducts were prepared using different conjugate acceptors and two different lithium benzylamides as nucleophiles. These adducts were easily converted in only one step, into the final, highly enantioenriched beta-amino esters
Etxebarria
Juan
J
Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/Euskal Herriko Unibertsitatea, P.O. Box 644, E-48080, Bilbao, Spain.
Vicario
Jose L
JL
Badia
Dolores
D
Carrillo
Luisa
L