Stereospecific Synthesis of Bicyclic β-Lactams via Metal-Catalyzed Carbonylative Coupling and Cyclization Reactions
作者:Zhongxin Zhou、Howard Alper
DOI:10.1021/jo9517104
日期:1996.1.1
Bicyclic beta-lactams were synthesized by the carbonylative coupling and cyclization reaction of 2-aryl-1,3-thiazines with allyl phosphates, catalyzed by bis(benzonitrile)palladium dichloride, using N,N-diisopropylethylamine as a base in tetrahydrofuran. Several rhodium complexes were also effective for this process. These transformations are stereospecific, with the aryl and vinyl groups on the beta-lactam ring being cis to each other. This methodology provides a novel route for the preparation of the cepham analogs, cis-7-vinyl-5-thia-1-azabicyclo[4.2.0]octan-8-ones.