Tf2O-Catalyzed Tandem Cyclization/Trifluoromethylselenolation of Alkynes for Synthesis of CF3Se-Containing Heterocycles.

Herein, the tandem synthesis of various CF3Se-containing heterocyclic compounds has been developed, using Tf2O as the catalyst and trifluoromethyl selenoxides as the electrophilic trifluoromethylselenolation reagents. This process is characterized by its mild conditions, ease of operation, and good functional group compatibility. A variety of alkynes could be transferred into CF3Se-containing indoles, benzofurans, benzothiophenes, isoquinolines and chromenes in good yields. A key step involving the formation of the electrophilic CF3Se species was proposed.