Aryl propargyl sulfides were subjected to electrochemical fluorination in dimethoxyethane (DME) containing various fluoride supporting electrolytes using an undivided cell to provide the corresponding alpha-monofluorinated or alpha,alpha-difluorinated sulfides selectively as main products in good yields depending on the amount of electricity passed. The alpha,alpha-difluorinated sulfides were stable enough to be isolated while the alpha-monofluorinated ones were very unstable. The alpha-monofluorinated sulfides were readily converted into the corresponding stable alpha-monofluoroallenyl sulfides in good yields. Furthermore, synthetic utility of alpha-monofluoroallenyl sulfides was also investigated. (C) 2002 Elsevier Science Ltd. All fights reserved.