Stereoselective Synthesis of <i>trans</i> β-Lactams through Iridium-Catalyzed Reductive Coupling of Imines and Acrylates
作者:Jennifer A. Townes、Michael A. Evans、Jerome Queffelec、Steven J. Taylor、James P. Morken
DOI:10.1021/ol020106u
日期:2002.7.1
[GRAPHICS]Iridium-catalyzed reductive coupling of acrylates and imines provides trans beta-lactams with high diastereoselection. The optimal catalyst allows for the synthesis of trans beta-lactams bearing aromatic, alkenyl, and alkynyl side chains. This reaction appears to proceed through a reductive Mannich addition-cyclization mechanism. Examination of substituent effects reveals a linear Hammett correlation for both the N-aryl group on the imine and the aryloxy group on the acrylate, thereby pointing to rate-determining cyclization in the reaction mechanism.
Streith, Jacques; Tschamber, Theophile, Liebigs Annalen der Chemie, 1983, # 8, p. 1393 - 1408