Diastereoselective bromodifluoromethylation and difluoromethylation of chiral imide enolates via insertion of difluorocarbene
作者:Katsuhiko Iseki、Daisuke Asada、Mie Takahashi、Takabumi Nagai、Yoshiro Kobayashi
DOI:10.1016/0957-4166(96)00127-9
日期:1996.4
Lithium enolates of chiral N-acyloxazolidinones reacted with dibromodifluoromethane and bromodifluoromethane to give α-bromodifluoromethyl and α-difluoromethyl carboximides, respectively, with good diastereomeric excess. These reactions proceed not via a radical mechanism but via an ionic chain mechanism involving insertion of difluorocarbene.
手性N-酰基恶唑烷酮的烯醇化锂与二溴二氟甲烷和溴二氟甲烷反应,分别得到α-溴二氟甲基和α-二氟甲基羧酰亚胺,非对映异构体过量。这些反应不是通过自由基机理而是通过涉及二氟卡宾插入的离子链机理进行。