Trifluoromethylation of Arylsilanes with [(phen)CuCF3]

Amethod for the trifluoromethylation of arylsilanes is reported. The reaction proceeds with [(phen)CuCF3] as the CF3 source under mild, oxidative conditions with high functional-group compatibility. This transformation complements prior trifluoromethylation of arenes in several ways. Most important, this method converts arylsilanes formed by the silylation of aryl C-H bonds to trifluoromethylarenes, thereby allowing the conversion of arenes to trifluoromethylarenes. The unique capabilities of the reported method are demonstrated by the conversion of a C-Hbond into a C-CF3 bond in active pharmaceutical ingredients which do not undergo this overall transformation by alternative functionalization processes, including a combination of borylation and trifluoromethylation.