A general method for the preparation of perfluoroalkanesulfonyl chlorides

A mild two-step synthesis of perfluoroalkanesulfonyl chlorides starting from perfluoroalkyl iodides has been developed. Reaction of perfluoroalkyl iodides with sodium dithionite gave sodium perfluoroalkanesulfinate salts which were converted into perfluoroalkanesulfonyl chlorides in 25–73% yield (two steps) using N-chlorosuccinimide.