Anodic gem-difluorination of hydrazones in Et4NF-5HF/CH2Cl2 in the presence of Et4NI was successfully carried out to provide the corresponding gem-difluorinated products in moderate to good yields. On the other hand, no gem-difluorinated products were obtained in the absence of Et4NI. Although a catalytic current was not observed in the cyclic voltammetry of Et4NI in the presence of a hydrazone, a controlled potential electrolysis of the hydrazone showed that Et4NI acted as a mediator in the anodic gem-difluorination of hydrazones. (c) 2006 Elsevier B.V. All rights reserved.