Electrochemical Investigations of Benzil in Nonaqueous Media

Abstract

Benzil has been found to undergo two successive reversible one-electron redox processes in the ionic liquid 1-butyl-1-methylpyrrolidinium trifluoromethanesulfonate (BMPY TfO). This behavior is observed due to the very low proton donating ability of the BMPY cation. Upon addition of acetonitrile, however, the second redox process becomes irreversible. The benzil dianion is evidently undergoing protonation by acetonitrile, and the resulting voltammogram is very similar to that in acetonitrile itself. The benzil dianion also undergoes protonation in adiponitrile.