1: 6-trifluoromethyl-1H-indole With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 0.5 h; 2: carbon dioxide in tetrahydrofuran; hexane T=-78°C; 0.333333 h; 3: carbon dioxide With hydrogenchloride; water; tert.-butyl lithium; ammonium chloride more than 3 stages;

potassium hydroxide

sodium hydroxide

1: aqueous NaOH 2: etheric diazoethane solution View Scheme