A Convenient Synthetic Approach to Saccharin Derivatives ­Containing a Sulfonylamidine Scaffold

A key intermediate was obtained as solid through filtration of the reaction mixture of saccharin, chloro(triphenyl)phosphonium chloride, and N , N -diisopropylethylamine (DIPEA) in chloroform. The soluble triphenylphosphine oxide went to filtrate as waste, while the solid was reacted with amines to afford N -sulfonylamidines. In total, 26 N -sulfonylamidine products were obtained in moderate to good overall yields.