Abstract Reactions of dialkyl ethers with either fluorine or Selectfluor™ led to the formation of unusual difluorinated polyether products in modest yields. A mechanism involving initial fluorination of the site adjacent to ether oxygen followed by elimination of hydrogen fluoride, reaction of the generated enol system with a further equivalent of fluorinating agent giving an oxonium system which reacts with water during aqueous work-up to lead eventually to the products observed, is suggested.