Catalysis

Organic synthesis

Dimethyl carbonate

Photochemistry

Metallurgy

Materials science

Rhodium

Coupling (piping)

Transition metal

Inorganic chemistry

Carbonate

Annulation

Acetylene

Oxidizing agent

Combinatorial chemistry

Organic chemistry

Oxidative coupling of methane

Chemistry

ACS Catalysis

Transition-metal-catalyzed C–H activation and subsequent oxidative cyclization with alkynes has been a powerful tool for the synthesis of polycyclic aromatic compounds. Despite the substantial progress in this field, it is still a significant challenge to establish synthetic methodologies for the construction of nonsubstituted vinylene-fused aromatics. We herein report a Rh(III)-catalyzed C–H/N–H annulation with vinylene carbonate as an acetylene surrogate. Vinylene carbonate also acts as an internal oxidant to regenerate the Rh(III) species in situ; thus, no external oxidant is required to trigger the oxidative annulation. This protocol is applicable to the direct synthesis of various N-heteroaromatics.

Rhodium-Catalyzed Annulative Coupling Using Vinylene Carbonate as an Oxidizing Acetylene Surrogate