Electrochemical reduction of phenyl(9-m-carboranyl)iodonium tetrafluoroborate

Abstract

This paper shows that the controlled-potential electrolysis (-0.4 V, s.c.e.) of phenyl(9-m-carboranyl)iodonium tetrafluoroborate (I) on a mercury cathode in a 0.05 M solution of Bu/sub 4/NBF/sup -//sub 4/ in DMF proceeds regiospecifically with breakage exclusively of the C-I bond in the cation of (I) to give 70% benzene (as indicated in gas-liquid chromatography) and 73% 9-iodo-m-carborane with a current yield of about 80%. These results support a previous hypothesis that all the reactions of phenyl(B-carboranyl)iodonium salts with nucleophiles, which accompany breakage of the C-I bond, proceed by the transfer of one electron from the nucleophile to the iodonium cation.