Cu-Mediated 2,2,2-trifluoroethylation of terminal alkynes using 1,1-dichloro-2,2,2-trifluoroethane (HCFC-123)

Abstract

The title reaction provides a novel utilization of ozone-depleting/global-warming HCFCs as a new carbon-carbon cross-coupling model of various terminal alkynes by activating two inert C-Cl bonds successively. This protocol provided trifluoroethylated alkynes efficiently under mild reaction conditions and was compatible with a broad range of functional groups. An example of the synthesis of a terbinafine analogue is shown. Some mechanistic experiments including deuterated reagents and radical/SET inhibitors are described.