Photocatalytic synthesis of dual acylmethylation derivates of indole[2,1-a]isoquinolinones via tandem cyclization/C3 acyl methylation

Abstract

We developed a method for the synthesis of indole[2,1-a]isoquinolinones under visible light using sulfoxonium ylides for the first time. 2-Aryl-N-methacrylindole and sulfoxonium ylides were used as starting materials through free-radical addition tandem cyclization and C3 acylmethylation, which is a novel and practical method for the one-pot construction of structurally novel dual acylmethylation derivatives of indole[2,1-a]isoquinolinones. This method provides an efficient and pratical means to obtain valuable indole[2,1-a]isoquinolinones under mild reaction conditions. In addition, preliminary mechanistic explorations were performed, leading to the proposal of a plausible catalytic cycle mechanism.