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An atom-economical and environmentally benign approach for the synthesis of 3-indolylquinones was achieved successfully via direct oxidative C–C coupling of quinones / hydroquinones with indoles using (NH4)2 S2 O8 in dichloroethane at 80 °C. The efficiency of this catalytic approach was established by a broad scope of substrates involving quinones and hydroquinones to give high yields (61–93%) of 3-indolylquinones. The present protocol is simple, practical, and show good functional group tolerance. In addition, the obtained 3-indolylnaphthoquinones were conducted to further transformation to synthesize 2-amino-3-indolylnaphthoquinone and polycyclic N -heterocycles, respectively. [ABSTRACT FROM AUTHOR]