Cobalt-Catalyzed Tandem Radical Cyclization/C-C Coupling Initiated by Directed C-H Activation.

A cobalt-N-heterocyclic carbene catalyst promotes a tandem radical cyclization/C-C coupling reaction between tosylamide-tethered bromo-alkenes and aryl N-H imines initiated by chelation-assisted arene C-H activation, affording 3-(arylmethyl)pyrrolidine derivatives in moderate to good yields. The reaction tolerates a variety of substituents on the aryl imine as well as various modifications on the bromo-alkene substrate.