Preference of beta-lactam formation in Cu(I)-catalyzed intramolecular coupling of amides with vinyl bromides.
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 of medium-sized lactams.
Zhao
Qiwu
Q
Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, PR China.
Li
Chaozhong
C
D000577:Amides / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D006801:Humans; D013379:Substrate Specificity; D014753:Vinyl Compounds / Q000737:chemistry*; D047090:beta-Lactams / Q000138:chemical synthesis* / Q000737:chemistry
D000577:Amides; D014753:Vinyl Compounds; D047090:beta-Lactams; D003300:Copper; C003763:vinyl bromide