Comments on the paper of A.T. D'Agostino and P.N. Ross: “on the importance of surface structure in electrochemistry: the well-defined Au (111) single crystal electrode surface”

The electroreduction of dimethylpyrrolidinium (DMP⁺) in diglyme on mercury cathodes was investigated. It was found to proceed via a fast one-electron transfer resulting in an insoluble “amalgam”. The DMP⁺ amalgam was reactive and transferred electrons to suitable substrate with regeneration of DMP⁺. Thus DMP⁺ could be used as a catalyst for electroreduction and this possibility was studied. It was found to be a suitable catalyst for the reduction of several difficult-to-reduce substrates (E_1/2 < ?2.8 V vs. SCE). Among others it effected the reduction of fluorobenzene, an aliphatic chloride, and simple conjugated dienes. A possible mechanism and the utility of the reaction are discussed.