A vitamin B 12 derivative catalyzed electrochemical trifluoromethylation and perfluoroalkylation of arenes and heteroarenes in organic media.

The electrochemical trifluoromethylation and perfluoroalkylation of aromatic compounds mediated by a vitamin B12 derivative as a cobalt-based catalyst has been developed. The Co(i) species of a vitamin B12 derivative, prepared by controlled-potential electrolysis at -0.8 V vs. Ag/AgCl in methanol, reacted with Rf I (Rf = CF3 , n-C3 F7 , n-C4 F9 , n-C8 F17 , and n-C10 F21 ) to form a Co-Rf complex. This complex released an Rf radical under visible light irradiation, which then reacted directly with non-activated (hetero)arenes to form the desired fluoroalkylated molecules through direct C-H functionalization. To our knowledge, this is the first report of a naturally derived vitamin B12 catalyzed trifluoromethylation and perfluoroalkylation of aromatic compounds as a cobalt-mediated catalyst.