Electroorganic chemistry provides a benign and practical approach to synthesis. Unfortunately some applications necessitate the use of large amounts of supporting electrolyte to ensure ionic conductivity and the efficient movement of charge. A major problem stems from the fact that the supporting electrolytes are difficult to separate, and when separated, they are frequently thrown away. To address these issues, a polymeric ionic liquid-Super P RTM carbon black composite has been formulated. The result is a stable electrolyte that enables electrolyses to be performed without adding an additional supporting electrolyte, and that can be efficiently recovered and reused. In addition, the ability of the composite to modify the electrode surface in situ leads to enhanced kinetics. A practical consequence is that one can decrease catalyst loading without sacrificing efficiency.

The present system promises to provide a general solution to problems associated with the use of conventional supporting electrolytes and ionic liquids. The system can be applied to a variety of synthetic transformations, and will undoubtedly find use in a host of other applications that necessitate the use of an electrolyte. In electroorganic synthesis, the generation of a reactive intermediate, e.g., a radical cation or a radical anion, can be achieved either directly or indirectly. In the former, the redox reaction of interest occurs at the electrode, while the latter uses an electron transfer redox mediator to achieve homogeneous electron transfer with the substrate. This electron transfer redox mediator plays a significant role in an indirect electrolysis since it is involved in the heterogeneous (at the electrode) as well as the homogeneous electron transfer step (with the substrate). Indirect electrolysis utilizing the redox mediator offers significant advantages over the direct protocol.

As a promising class of organic electron transfer redox mediators, the recently developed triarylimidazoles (TAIs) have been used to achieve indirect electrochemical C-H bonds activation and functionalization. Herein the diffusion and electron transfer rates for the oxidation of 4-methoxybenzyl alcohol using TAI are reported and compared its electrochemical behavior with that of tris(4-bromophenyl)amine (TBPA), an organic electron transfer mediator that is frequently used for indirect oxidative electrolysis. The results contribute to the understanding of the electron transfer process of electrocatalytic oxidation using TAIs, and offer useful guidelines for their further development and use.