A novel synthetic route to ethyl 3-substituted-trans-2,3-difluoro-2-acrylates and their reactions with nucleophiles
作者:Qisheng Zhang、Long Lu
DOI:10.1016/s0040-4039(00)01517-3
日期:2000.10
Reaction of a variety of trans-1-trimethylsilyl-1,2-difluoroalkenes with ethyl chloroformate in the presence of potassium fluoride gave the corresponding ethyl 3-substituted-trans-2,3-difluoro-2-acrylates in good yields, which reacted with a variety of nucleophiles such as hydrazine hydrate, amidines and thiourea etc. in the presence of bases to afford the corresponding 4-fluoropyrazole, 5-fluoropyrimidine