We have developed a novel electrolytic system for indirect anodic oxidation based on the cation exchange reaction between alkaline (earth) metal halides and solid-supported acids. It was demonstrated that hydrogen halides derived from the cation exchange reaction act as not only a supporting electrolyte but also a mediator in acetonitrile. On the basis of the electrolytic system, indirect anodic oxidation of various benzyl alcohols in the presence of 2,6-lutidine was successfully achieved by controlled potential electrolysis to provide the corresponding benzaldehydes in good to excellent yields. (c) 2008 Elsevier B.V. All rights reserved.