Ir-Catalyzed Intramolecular Transannulation/C(sp2)–H Amination of 1,2,3,4-Tetrazoles by Electrocyclization

An efficient strategy for the intramolecular denitrogenative transannulation/C(sp 2 )–H amination of 1,2,3,4-tetrazoles bearing C8-substituted arenes, heteroarenes, and alkenes is described. The process involves the generation of the metal–nitrene intermediate from tetrazole by the combination of [Cp*IrCl 2 ] 2 and AgSbF 6 . It has been shown that the reaction proceeds via an unprecedented electrocyclization process. The method has been successfully applied for the synthesis of a diverse array of α-carbolines and 7-azaindoles.