Palladium-Catalyzed One-Pot Synthesis of N-Sulfonyl, N-Phosphoryl, and N-Acyl Guanidines

An efficient palladium-catalyzed cascade reaction of azides with isonitrile and amines is presented; it offers an alternative facile approach toward N-sulfonyl-, N-phosphoryl-, and N-acyl-functionalized guanidines in excellent yield. These series of substituted guanidines exhibit potential biological and pharmacological activities. In addition, the less reactive intermediate benzoyl carbodiimide could be isolated by silica gel column flash chromatography in moderate yield.