Interception of Secondary Amide Ylide with Sulfonamides: Catalyst-Controlled Synthesis of N-Sulfonylamidine Derivatives.

A novel, secondary amide activation strategy has been developed through the in situ generation of ylides from amides and diazoacetates. Under the developed reaction conditions, Mn-catalyzed ylide formation and interception reaction by sulfonamide delivered a variety of N-sulfonylamidines. Notably, when highly active Zn(OTf)2 was used as the catalyst, further N-H insertion products were obtained. In contrast with traditional methods, our amide activation strategy is distinguished by accessible starting material, inexpensive catalyst, and broad substrate scope.