Electrolytic partial fluorination of organic compounds - Part 25. Regioselective anodic fluorination of naphthalene- and pyridine-acetate and -acetonitrile derivatives

Anodic regioselective fluorination of alpha-phenylsulphenylated ethyl acetates and acetonitriles of I-naphthalene and 2-pyridine derivatives was investigated. 1-Naphthalene derivatives were selectively fluorinated at the alpha-carbon using Et3N . 3HF/CH3CN in high yields while those devoid of an alpha-phenylsulphenyl group gave non-regioselectively polyfluorinated products. On the contrary, alpha-phenylsulphenylated 2-pyridine derivatives gave the corresponding alpha-fluoro compounds in low yields in CH3CN. The fluorinated products were obtained in much better yields in DME. Moreover, their yields were significantly improved by the addition of Ph2S. (C) 1998 Elsevier Science S.A.