1: 1H-Pyrrolo[2,3-b]pyridine With n-butyllithium in tetrahydrofuran; hexane T=-70°C; 0.25 h; 2: carbon dioxide in tetrahydrofuran; hexane T=-70 - 20°C; 3: carbon dioxide With hydrogenchloride; water; tert.-butyl lithium more than 3 stages;