Synthesis of 3-Arylindole-2-carboxylates via Copper-Catalyzed Hydroarylation of o-Nitrophenyl-Substituted Alkynoates and Subsequent Cadogan Cyclization

A two-step route to biologically important 3-arylindole-2-carboxylic esters has been successfully established: o-nitrophenyl-substituted alkynoates underwent copper-catalyzed hydroarylation in the presence of commercially available arylboronic acids to afford 3,3-diarylacrylates, which were then converted to indolecarboxylates via a modified Cadogan cyclization using a molybdenum catalyst and triphenylphosphine.