Preference of β-Lactam Formation in Cu(I)-Catalyzed Intramolecular Coupling of Amides with Vinyl Bromides
作者:Qiwu Zhao、Chaozhong Li
DOI:10.1021/ol801545a
日期:2008.9.18
A general and highly efficient synthesis of 4-alkylidene-2-azetidinones was achieved by the Cu(I)-catalyzed intramolecular C-N coupling of amides with vinyl bromides. This 4-exo ring closure was found to be fundamentally preferred over other modes (5-exo, 6-exo, and 6-endo) of cyclization under copper catalysis. Tandem C-N bond formation was then successfully developed to allow the convenient generation