Anodic fluorination of various kinds of five-membered cyclic thiocarbonates was carried out under various electrolytic conditions and the corresponding alpha-monofluorinated products were obtained in the cases of 1,3-oxathiolane-2-one and 1,3-dithiolane-2-one with high regioselectivity. On the contrary, oxidative desulfurization of cyclic thiocarbonates with a C=S bond took place to provide the corresponding gem-difluorinated product and/or carbonyl compounds depending on the molecular structures of the starting thiocarbonates. (c) 2005 Elsevier Ltd. All rights reserved.