Access to Indenones by Rhodium(III)-Catalyzed C-H Annulation of Arylnitrones with Internal Alkynes

Under redox-neutral conditions, rhodium(III)-catalyzed C-H annulation of N-tert-butyl-alpha-arylnitrones with internal alkynes has been realized for the synthesis of indenones under mild conditions. This reaction proceeded in moderate to high yields and with good functional group tolerance.