An isocyanide insertion approach to substituted pyrrolo[2,3-b]quinolines under metal-free and azide-free conditions

A new strategy for the catalytic synthesis of the pyrrolo[2,3-b]quinoline skeleton by the reaction of isocyanides with (cyclopropylidene(aryl)methyl)aniline (amino-MCPs) is presented, taking advantage of I2/CHP mediated carbodiimide intermediate generation. This reaction involves three C–N bonds and one C–C bond generation under metal-free and azide-free conditions.