Blaise Reaction of Ethyl 3-Bromodifluoromethyl-3-benzyloxyacrylate with Nitriles: A Convenient Synthesis of α-Difluorovinyl-Substituted β-Enaminoesters and β-Ketoesters
作者:Shizheng Zhu、Weimin Peng、Jingwei Zhao
DOI:10.1055/s-2006-926436
日期:2006.5
The Blaise reaction between the zinc dienolate of ethyl 3-bromodifluoromethyl-3-benzyloxyacrylate and a variety of nitriles gave a series of a-difluorovinyl substituted beta-enaminoesters in good yield, which readily underwent hydrolysis to the corresponding beta-ketoesters. Direct coupling of this zinc dienolate with acyl chloride also furnished the same a-difluorovinyl substituted beta-ketoester
Nucleophilic Addition of Ethyl 3-Bromodifluoromethyl-3-benzyloxyacrylate to Imines: An Effective Entry to Novel g<i>em</i>-Difluorinated Amino Esters and their Derivatives
作者:Shizheng Zhu、Weimin Peng、Jingwei Zhao、Ping He
DOI:10.1055/s-2006-926225
日期:——
Zinc- or tetrakis(dimethylamino)ethylene (TDAE)-mediated nucleophilic addition of ethyl 3-bromodifluoromethyl-3-benzyloxyacrylate to imines afforded gem-difluorovinyl substituted β-amino esters (α-addition product) and gem-difluorinated δ-amino esters (γ-addition product) or their cyclized derivatives, depending on the mediator and the nature of substituents on the imines.
Synthetic applications of ethyl 3-bromodifluoromethyl-3-benzyloxy-acrylate as a gem-difluorination building-block: Its reactions with aldehyde and epoxide
作者:Weimin Peng、Jingwei Zhao、Shizheng Zhu
DOI:10.1016/j.jfluchem.2005.12.017
日期:2006.3
tetrakis(dimethylamino)ethylene (TDAE) promoted reaction with a limited scope of aldehyde produced Barbier reaction mode product, δ-hydroxy ester, in moderate yield. The reaction of its zinc reagent with styrene oxide resulted in rearrangement of the epoxide to 2-phenyl-acetaldehyde, and then the zinc reagent condensed with this aldehyde to provide the Reformastsy reaction type product, β-hydroxy ester, in low