3-Bromo-5-chloropyridin-2-amine (10 g, 49 mmol) and chloroacetaldehyde (50% aqueous, 12 mL, 98 mmol) were mixed in ethanol (100 mL) and the reaction was heated at 50 °C overnight. Upon completion of the reaction, the mixture was cooled to room temperature and concentrated. To the concentrated residue was added acetone (30 mL) and stirred rapidly for 2 hours. The resulting solid was collected by filtration and dried to afford the target product 8-bromo-6-chloroimidazo[1,2-a]pyridine (10.0 g, 89% yield). Mass spectrometry analysis showed [M + H]+ peak of 231. 1H NMR (500 MHz, DMSO) data were as follows: δ 9.20 (s, 1H), 8.33 (s, 1H), 8.29 (s, 1H), 8.09 (s, 1H).
![8-Bromo-6-chloroimidazo[1,2-a]pyridine](/CAS/GIF/957187-27-8.gif)