Selective, efficient and functional group-tolerant CuOAc-mediated N-arylation of 1H-indoles and 9H-carbazole with aryl iodides under base-free and ligandless conditions

CuOAc-Mediated N-arylation of 1H-indole derivatives and 1H-carbazole with aryl iodides under base-free and ligandless conditions provides the required N-arylazoles with complete N-selectivity and in moderate to good yields. The experimental conditions for this new version of the Ullmann reaction allow an unprecedented tolerance of functional groups and facilitate the workup of the reaction mixtures and isolation of the required chemically pure reaction products. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007).