Electrochemical Trifluoromethylation of Glycals.

Carbohydrates play essential roles in various physiological and pathological processes. Trifluoromethylated compounds have wide applications in the field of medicinal chemistry. Herein, we report a practical and efficient trifluoromethylation of glycals by an electrochemical approach using CF ₃ SO ₂ Na as the trifluoromethyl source and MnBr ₂ as the redox mediator. A variety of trifluoromethylated glycals bearing different protective groups are obtained in 60-90% yields with high regioselectivity. The successful capture of a CF ₃ radical indicates that a radical mechanism is involved in this reaction.