The Electrochemical Fluorination of Benzenes and Pyridines

Abstract The electrochemical fluorination of several aromatic compounds (benzene, fluorobenzene, chlorobenzene, m-dichlorobenzene, anisole, o-chloroanisole, thiophenol, p-chlorothiophenol, m-thiocresol, 2-chloropyridine, and 3-chloropyridine) has been carried out. Perfluorocyclohexane was the principal product from benzene and fluorobenzene. In addition, chloro-derivatives of perfluorocyclohexane were produced from chlorobenzenes. Anisoles gave fully-saturated perfluoroethers, together with cleaved products. Extensive cleavage was observed in the fluorination of thiophenols and chloropyridines, and fluorocarbons and sulfur hexafluoride or nitrogen trifluoride were characteristic products. New compounds were also formed, trifluoromethyl 2-chlorodecafluorocyclohexyl ether from o-chloroanisole, and 3-chlorodecafluoropiperidine and 2-chloroundecafluoropentane from 3-chloropyridine.