Synthesis of sulfonamides and sulfonic esters via reaction of amines and phenols with thiols using H2O2–POCl3 system

Phosphorus oxychloride efficiently promoted the synthesis of sulfonamides and sulfonic esters from thiols with hydrogen peroxide in the presence of Amberlite IRA-400 (OH−). This method has been applied to a variety of substrates including nucleophilic and sterically hindered amines, and also phenols with excellent yields of sulfonamides and sulfonic esters. In most cases these reactions are highly selective, simple, and clean, affording products in excellent yields and high purity.