One-pot synthesis of -sulfonylamidines from -acylsulfonamides enabled by a metal triflate-mediated nonhydrolytic -deacylation.

A triflate salt-catalyzed nonhydrolytic method for the deacylation of -acylsulfonamides and subsequent one-pot condensation of the newly formed sulfonamides with ,-dimethylformamide dimethyl acetal to provide -sulfonylamidines is presented. A range of aliphatic and aromatic -acylsulfonamides bearing various -acyl groups such as acetyl, propionyl, butyrl, isobutyryl, octanoyl, benzoyl, 2-phenylacetyl, and sterically hindered pivaloyl are readily transformed into the corresponding -sulfonylamidines in good to excellent yields. A variety of functional groups including halogeno, keto, nitro, cyano, hydroxyl, ether, and carboxylic ester are tolerated intact.