Synthesis
To a solution of 6-bromopyridin-3-amine (5.4 g, 28.9 mmol) in dichloromethane (200 mL) was sequentially added triethylamine (4.4 g, 43.3 mmol) and di-tert-butyl dicarbonate (7.6 g, 34.7 mmol). The reaction mixture was stirred at room temperature for 4 h. After completion of the reaction, the reaction was quenched with water (300 mL). The organic layer was separated and dried over anhydrous sodium sulfate. The desiccant was removed by filtration and the filtrate was concentrated under reduced pressure, the resulting residue was purified by silica gel column chromatography with the eluent being a petroleum ether solution of 2-10% ethyl acetate to afford the target product, tert-butyl (6-bromopyridin-3-yl)carbamate, as a colorless solid. Mass spectra (ESI, m/z): 273.1, 275.1 [M + 1]+; 1H NMR (300 MHz, DMSO-d6) δ 9.72 (s, 1H), 8.45 (d, J = 1.8 Hz, 1H), 7.83 (d, J = 5.4 Hz, 1H), 7.53 (d, J = 5.7 Hz, 1H), 1.48 (s, 9H) .
References
[1] Patent: WO2015/188368, 2015, A1. Location in patent: Page/Page column 114
[2] Journal of Medicinal Chemistry, 2010, vol. 53, # 24, p. 8709 - 8715
[3] Chemistry - A European Journal, 2010, vol. 16, # 30, p. 9056 - 9067
[4] Patent: WO2017/207813, 2017, A1. Location in patent: Page/Page column 126
[5] Patent: WO2006/92599, 2006, A2. Location in patent: Page/Page column 58-59
