The reactions of aryl and alkyl sulfonamides with oxalyl chloride have been investigated. The uncatalyzed reaction produced sulfonyloxamides or sulfonyloxamoyl chlorides depending on the mole ratio of reactants. In the presence of a tertiary amine catalyst, however, the major products were sulfonylparabanates or mixtures of sulfonyl isocyanate and sulfonyl chloride. Probable mechanisms of these transformations are discussed. ...
