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

The CuOAc-mediated N-arylation of 1H-indole derivatives and 1H-carbazole with aryl iodides under base-free and ligandless conditions provides with complete N-selectivity the required N-arylazoles in moderate to good yields. The experimental conditions of this new version of the Ullmann reaction allow an unprecedent tolerance of functional groups and facilitate the work-up of the reaction mixtures and isolation of the required chemically pure reaction products.