Rhodium(III)-Catalyzed Synthesis of Indole Derivatives from Pyrimidyl-Substituted Anilines and Diazo Compounds.

An efficient method for the synthesis of indole derivatives from readily available pyrimidyl-substituted anilines and diazo compounds via rhodium(III)-catalyzed CH bond activation has been developed. This cyclization reaction displays excellent functional group compatibility and regioselectivity, which overcomes some drawbacks of the classical indole synthetic methods and provides a facile approach for the construction of multi-substituted indole derivatives. The redox-neutral intermolecular annulation procedure comprises tandem CH bond activation, cyclization, and condensation steps, releasing water and nitrogen as by-products.