1: tert-butyl 2-((ethoxycarbonyl)methyl)-1H-indole-1-carboxylate With potassium hexamethylsilazane in tetrahydrofuran T=-78 - -60°C; 1 h; 2: methyl iodide in tetrahydrofuran T=20°C; 0.5 h; 3: methyl iodide With potassium hexamethylsilazane more than 3 stages;

in tetrahydrofuran; hexane; ethyl acetate

potassium hexamethylsilazane

potassium hexamethylsilazane in tetrahydrofuran; toluene T=-78°C; 0.5 h; Yield given;