1188477-11-3

GENERAL STEPS: To a solution of 5-bromo-2-cyanopyridine (3.0 g, 16.4 mmol) in methanol (60 mL) was sequentially added di-tert-butyl dicarbonate (7.2 g, 32.8 mmol) and nickel chloride hexahydrate (0.33 g, 1.64 mmol). The reaction mixture was cooled to 0 °C, followed by the addition of sodium borohydride (4.3 g, 0.115 mol) in batches over a period of 2 hours. The reaction mixture was continued to be stirred at 15 °C for 1 h, after which it was poured into ice water (200 g) and extracted with ethyl acetate. The organic layers were combined, washed with saturated brine, dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was purified by fast column chromatography to afford the target product tert-butyl (5-bromopyridin-2-ylmethyl)carbamate (2.2 g, 47% yield) as a yellow solid. m/z 287,289 ([M+H]+) by LC-MS.

[1] Patent: WO2016/112088, 2016, A1. Location in patent: Paragraph 0660
[2] Patent: US2013/237502, 2013, A1. Location in patent: Paragraph 0367
[3] Patent: WO2018/42342, 2018, A1. Location in patent: Page/Page column 53