Synthesis
To a solution of 4-bromopyridin-2-amine (3.11 g, 17.98 mmol) in dichloromethane (60 mL) at 0 °C were sequentially added acetyl chloride (1.406 mL, 19.77 mmol) and pyridine (1.745 mL, 21.57 mmol). The reaction mixture was slowly warmed to room temperature and stirred continuously for 2 hours. Upon completion of the reaction, the reaction was quenched with water and diluted with ethyl acetate. The organic layer was separated, washed sequentially with water and saturated saline, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to afford N-(4-bromopyridin-2-yl)acetamide (3.82 g, 17.05 mmol, 95% yield) as a white solid. The obtained product could be used in the subsequent reaction without further purification.LCMS (ESI) m/e 215.0 [(M + H)+, calculated value C7H8Br1N2O2, 215.0]; LC/MS retention time (Method A): 2.61 min.
References
[1] Patent: WO2014/140077, 2014, A1. Location in patent: Page/Page column 60
[2] Patent: WO2015/153720, 2015, A1. Location in patent: Page/Page column 20; 21
[3] Patent: WO2017/59085, 2017, A1. Location in patent: Page/Page column 20; 21
[4] Patent: WO2014/78257, 2014, A1. Location in patent: Page/Page column 118
[5] Patent: WO2015/116492, 2015, A1. Location in patent: Page/Page column 80
