Copper-Catalyzed Direct Synthesis of 3-Arylindoles

A direct method for the preparation of various 3-arylindoles from their corresponding nitrosoarenes has been developed. Various substituted nitrosoarenes and alkynes were employed to obtain substituted indoles by using a Cu-II-Cu-0 catalytic system. This is a two-step method that involves annulation of the nitrosoarene and alkyne followed by deoxygenation to give 3-arylindoles.