A two-step,
on-water procedure for the synthesis of ethenesulfonyl
fluoride (ESF) is described. 2-Chloroethanesulfonyl fluoride is made
via a neat reaction with an aqueous, nearly saturated potassium bifluoride
solution from readily available 2-chloroethanesulfonyl chloride. The
subsequent dehydrochlorination of 2-chloroethanesulfonyl fluoride
proceeds neatly with magnesium oxide as the base in an aqueous suspension
to give ESF. This recipe allows the preparation of ESF in 98% yield
on a kilogram scale