Silver-catalyzed vinylic C-F bond activation: Synthesis of 2-fluoroindoles from β,β-difluoro-o-sulfonamidostyrenes

Abstract

An electrophilic 5-endo-trig cyclization of β,β-difluoro-o-sulfonamidostyrenes was performed in 1,1,1,3,3,3-hexafluoropropan-2-ol using a Ag(I) catalyst and N,O-bis(trimethylsilyl)acetamide. In this process, vinylic C-F bond activation was achieved via silver-catalyzed β-fluorine elimination, accompanied by C-N bond formation, which led to the synthesis of 2-fluoroindoles.