General procedure for the synthesis of 7-bromoimidazo[1,5-a]pyridine from N-((4-bromopyridin-2-yl)methyl)formamide: To a 100 mL round bottom flask was added a solution of N-((4-bromopyridin-2-yl)methyl)formamide (Compound 39.2, 3.0 g, 90%, 12.6 mmol) in dichloromethane (20 mL). The solution was cooled to 0-5 °C and then trifluoroacetic anhydride (1.93 mL, 13.9 mmol) was added dropwise. The reaction mixture was stirred at room temperature for 1 h. Subsequently, the pH was adjusted to 7 by slow addition of saturated aqueous sodium carbonate solution. The aqueous phase was extracted with dichloromethane (3 x 20 mL), the organic layers were combined and washed with brine (3 x 20 mL). The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography using ethyl acetate/petroleum ether (1/1) as eluent to afford 7-bromoimidazo[1,5-a]pyridine as a brown solid.
![7-bromoimidazo[1,5-a]pyridine Structure](/CAS/20180629/GIF/865156-48-5.gif)
