Rhodium(III)‐Catalyzed Synthesis of Cinnolinium Salts from Azobenzenes and Diazo Compounds

Abstract A Rh(III)‐catalyzed C−H activation of azobenzenes in the coupling with diazo compounds has been realized, providing a straightforward strategy to access functionalized cinnolinium triflates in high yields. This protocol features silver free mild reaction conditions and compatibility with diverse functional groups. The coupling proceeds via initial Rh(III)‐catalyzed C−H alkylation, followed by zinc triflate‐mediated cyclization, where zinc triflate acts as a Lewis acid as well as a triflate source. magnified image