Reaction of thiolsulfinates with trihaloacetic anhydrides—I : Evidence for the formation of sulfenyl and sulfinyl carboxylates

Thiolsulfinates react with trifluoro- or trichloroacetic anhydride to give equimolar mixtures of the corresponding disulfides and sulfinyl trifluoro- or trichloroacetates which are in equilibria with sulfenyl carboxylates. Although the equilibrium lies far toward sulfinyl carboxylates at room temperature, addition of olefins to the mixed solution of sulfinyl carboxylate and a corresponding disulfide affords the adducts which are formed in the reaction between the corresponding sulfenyl carboxylates and the olefins. Meanwhile, treatment of carboxylic acid silver salts with sulfinyl chlorides also gives sulfinyl carboxylates, however, sulfinyl carboxylates have not been successfully isolated yet.