General and Efficient Synthesis of Indoles through Triazene-Directed C–H Annulation


  • This work is financially supported by grants of the National Basic Research Program of China (2010CB833201, 2012CB722602), grants of Shenzhen special funds for the development of biomedicine (JC201104210111A, JC201104210112A), Shenzhen innovation funds (GJHZ20120614144733420), and the Shenzhen Peacock Program (KQTD201103).


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Unprotected indoles are prepared with the title method, which has a wide scope for alkynes. Excellent regioselectivity was accomplished for aryl–alkyl and alkyl–alkyl disubstituted acetylenes. This reaction features an unusual 1,2 rhodium migration and ring-contraction-triggered N[BOND]N bond cleavage. It allows rapid conversion of the reaction products into several functional molecules.