A stable, scalable fluorosulfonyl tetrafluoroethoxylating reagent 1,1,2,2-tetrafluoro-2-(fluorosulfonyl)ethyl benzoate as a versatile surrogate of tetrafluoroethane β-sultone was developed. This reagent enables the concomitant introduction of a halogen (iodine, bromine, or chlorine) and a fluorosulfonyltetrafluoroethoxy group across the double bond of alkenes, a transformation termed halofluorosulfonyl tetrafluoroethoxylation. Subsequent elimination of the brominated adducts provides efficient access to bifunctional styrenyl fluorosulfonyl tetrafluoroethyl ethers, which are promising monomers for perfluorosulfonic acid (PFSA) ionomers. Its utility is further demonstrated in diverse transformations, including nucleophilic substitutions, alkyne additions, and esterifications, as well as preparation of photoacid generators (PAGs), establishing it as a robust and multifaceted building block for organofluorine chemistry.
Chen et al. (Thu,) studied this question.