Diphosphonium fluorosulfonate reagent as a dehydrating agent in organic synthesis

Abstract A facile, one-pot dehydration of organic substrates is afforded by the ‘diphosphonium fluorosulfonate’ reagent, Ph 3 P + OP + Ph 3 ·2SO 3 F − . This reagent has been used to convert acids to anhydrides, acid and alcohols to esters, acids and amines to amides and in double dehydrations to form heterocycles.