Trifluoromethyl-Substituted Sulfonium Ylide: Rh-Catalyzed Carbenoid Addition to Trifluoromethylthioether

A highly efficient Rh-catalyzed carbenoid addition to trifluoromethylthioether for the formation of trifluoromethyl-substituted sulfonium ylide is described. The trifluoromethyl-substituted sulfonium ylide can act as an electrophilic trifluoromethylation reagent, as demonstrated by trifluoromethylation of β-ketoesters and aryl iodides.