Copper-catalyzed amino radical tandem cyclization toward the synthesis of indolo-[2,1-a]isoquinolines

We report a convenient process for synthesizing indolo-[2,1-a]isoquinoline tetracyclic skeletons in one pot via a low-cost copper-catalyzed tandem amino radical cyclization, in which one C–C bond and one C–N bond are synchronously established. A range of valuable indolo-[2,1-a]isoquinoline derivatives bearing various groups was obtained under mild conditions.