Synthesis of Tetrasubstituted Pyrroles from Terminal Alkynes and Imines

Tetrasubstituted pyrroles can be obtained via the reaction of terminal alkynes and Imines using (BuLi)-Bu-n as the base In one step with high chemoselectivity (method 1). Alternatively, the intermediate propargylamines can also react with imines to afford tetrasubstituted pyrroles when using LiHMDS as the base (method 2), which provides a complementary method to construct the pyrroles with different substituents.