1: ethyl-5-methoxy-3-methyl-1H-indole-2-carboxylate With sodium hydride in N,N-dimethyl-formamide T=0°C; 0.666667 h; 2: methyl iodide in N,N-dimethyl-formamide T=20°C; 2 h; Further stages.;

1.1: NaNO2; aq. HCl / 0 °C 1.2: KOH 1.3: 62 percent / HCl / ethanol / Heating 2.1: sodium hydride / dimethylformamide / 0.67 h / 0 °C 2.2: dimethylformamide / 2 h / 20 °C View Scheme