1: 5-bromo-4-chloro-7-methyl-7H-pyrrolo[2,3-d]pyrimidine With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 1 h; 2: carbon dioxide in tetrahydrofuran; hexane T=25°C; 3: With hydrogenchloride in tetrahydrofuran; hexane; water

1.1: N-bromosuccinmide / dichloromethane / 2 h / 0 - 25 °C 2.1: n-butyllithium / hexane; tetrahydrofuran / 1 h / -78 °C 2.2: 25 °C View Scheme