Selenium-Catalyzed Oxidative C(sp2)-H Amination of Alkenes Exemplified in the Expedient Synthesis of (Aza-)Indoles

A new selenium-catalyzed protocol for the direct, intramolecular amination of C(sp(2))-H bonds using N-fluorobenzenesulfonimide as the terminal oxidant is reported. This method enables the facile formation of a broad range of diversely functionalized indoles and azaindoles derived from easily accessible ortho-vinyl anilines and vinylated aminopyridines, respectively. The procedure exploits the pronounced carbophilicity of selenium electrophiles for the catalytic activation of alkenes and leads to the formation of C(sp(2))-N bonds in high yields and with excellent functional group tolerance.