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General procedure for the synthesis of 2-amino-6-bromoimidazo[1,2-a]pyridine from N-(6-bromoimidazo[1,2-a]pyridin-2-yl)-2,2,2-trifluoroacetamide: N-(6-bromoimidazo[1,2-a]pyridin-2-yl)-2,2,2-trifluoroacetamide (5.5 g, 18.2 mmol) and lithium hydroxide (1.2 g. 27.3 mmol) were dissolved in THF/water (50 mL, 7:3) mixed solvent and the reaction was stirred at room temperature for 24 hours. After completion of the reaction, THF was removed by distillation under reduced pressure and the aqueous phase was extracted with dichloromethane (DCM). The organic layers were combined, washed with saturated brine, dried over anhydrous sodium sulfate and concentrated under reduced pressure to give 2-amino-6-bromoimidazo[1,2-a]pyridine (2.9 g, 77% yield) as a light brown solid. The product was analyzed by HPLC (X-Terra column), retention time (Rt): 3.07 min (purity: 97.0%).LC/MS (Atlantis column) showed the molecular ion peak [M+H]+ (ESI): 214.1.1.1H-NMR (DMSO-d6, 400 MHz) δ: 8.58-8.59 (1H, s) , 7.11-7.13 (1H, d), 7.05-7.07 (1H, d), 6.98 (1H, s), 5.19 (2H, s).

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