Copper-Catalyzed [2,3]-Sigmatropic Rearrangement of Azide-Ynamides via Selenium Ylides.

A copper-catalyzed [2,3]-sigmatropic rearrangement of azide-ynamides via selenium ylides is disclosed, which leads to the practical and divergent synthesis of a variety of tricyclic heterocycles bearing a quaternary carbon stereocenter in generally moderate to excellent yields. Significantly, this method represents the first [2,3]-sigmatropic rearrangement of the selenium ylide based on alkynes and an unprecedented [2,3]-sigmatropic rearrangement via α-imino copper carbenes.