Access to Functionalized Bicyclo[4,3,0]nonenes via Palladium-Catalyzed Oxidative Cyclization of 2-Allylcyclohexyl Oximes
作者:Jia-Liang Zhu、Sih-Ting Wu、Jr-Yun Shie
DOI:10.1021/jo5005422
日期:2014.4.18
A new palladium-catalyzed oxidative cyclization process leading to the functionalized bicyclo[4,3,0]nonenes is serendipitously discovered during attempts to form azaheterocycle by the amino-Heck reaction of trans-2-vinyl-clohexyl phosphinyloxime. Under the influence of Pd(dba)(2)/Et3N/1:1 N-2-O-2 (1:1, v/v) (Method A) or Pd(OAc)(2)/Et3N/O-2 (Method B), the reactions afford the substituted cis-1-hydroxyl-8-formyl-bicyclo[4,3,0]non-8(9)-enes or bicycle[4,3,0]non-1(9)-en-8-ones in varying yields with the incorporation of molecular oxygen into the structures. The 5,6-bicyclic scaffold of these products is presumably derived from tandem double intramolecular cyclization followed by the ring-opening of an aza-palladium(II) tricyclic intermediate.