1: 4-nitro-1H-indole; methyl-magnesium chloride With N,N,N',N',N'',N''-hexamethylphosphoric triamide in tetrahydrofuran T=-30°C; 0.25 h; 2: With lead(IV) acetate; acetic acid in tetrahydrofuran; dichloromethane T=-30 - 20°C; 3: benzenesulfonyl chloride With sodium hydroxide in dichloromethane T=20°C; 0.5 h;

1: With tris(N,N-dimethylamino)methane in N,N-dimethyl-formamide T=105°C; 3 h; 2: With potassium permanganate in tetrahydrofuran; water T=20°C; 3 h;

1.1: tris(dimethylamino)methane / dimethylformamide / 3 h / 105 °C 1.2: 70 percent / KMnO4 / tetrahydrofuran; H2O / 3 h / 20 °C 2.1: Na2S2O4 / tetrahydrofuran; H2O / 1 h / 50 °C View Scheme

1.1: tris(dimethylamino)methane / dimethylformamide / 3 h / 105 °C 1.2: 70 percent / KMnO4 / tetrahydrofuran; H2O / 3 h / 20 °C 2.1: Na2S2O4 / tetrahydrofuran; H2O / 1 h / 50 °C 3.1: 2.6 g / N,N-dimethyl-acetamide / 4 h / 150 °C View Scheme