Reactions involving hexafluoropropylene oxide. Part 2. A novel "dethioesterification" of a fluorinated sulfur containing ester

Ring opening reactions of hexafluoropropylene oxide (HFPO) 1 with thiopheno l gave the thioesters, 2, 6 and 7 depending on the conditions used to activ ate the thiol group. Saponification of the eater 2 led, in a slow reaction, to the acid 3. In an attempt to improve the saponification of thioester 2 the use of silver nitrate in dioxane-water surprisingly led to the formatio n of the hydro compound 4 via a novel "dethioesterification" reaction. The potential use of the chemistry described for the introduction of fluorinate d functions stereospecifically is discussed.