Co(III)-Catalyzed Three-Component Cascade for the Synthesis of α-Quaternary Acyclic Nitriles via C–H Bond Activation

Herein, we developed a cobalt-catalyzed three-component strategy to synthesize α-quaternary aliphatic nitriles in good yields. This protocol proceeds through the sequential addition of indoles, dienes, and N-cyanosuccinimide. The scope of this method has been extensively explored with various substituted N-pyrimidyl-indoles. Terminally substituted diene and 1,2-disubstituted diene also participated in the reaction. Notably, N-pyridyl-2-pyridones are also compatible with this protocol. The synthesized nitrile product was further converted into a tetrazole derivative. A plausible reaction mechanism is proposed to account for the present transformation.