Synthesis
IV. General procedure for the synthesis of 5-trifluoromethylpyridine-2-methanol: To a solution of methyl 5-trifluoromethylpyridine-2-carboxylate (2 g, 9.75 mmol) in methanol (30 mL) was added sodium borohydride (738 mg, 19.5 mmol) in one batch at 0 °C. The reaction mixture was stirred at room temperature for 2 hours and then concentrated. The residue was diluted with water (30 mL), acidified with 1N hydrochloric acid to pH ~5, and extracted with ethyl acetate (3 x 50 mL). The organic phases were combined, dried over anhydrous sodium sulfate and concentrated, and finally purified by silica gel column chromatography to afford 5-trifluoromethylpyridine-2-methanol as a colorless oil (1.6 g, 93% yield).1H NMR (400 MHz, CDCl3) δppm: 8.82 (s, 1H), 7.90-7.92 (m, 1H), 7.40-7.42 (m, 1H ), 4.82-4.83 (m, 2H), 3.44-3.46 (m, 1H); ES-LCMS m/z 178 ([M+H]+).
References
[1] Patent: WO2013/166621, 2013, A1. Location in patent: Page/Page column 48
[2] Patent: CN106831840, 2017, A. Location in patent: Paragraph 0102; 0103; 0104
[3] Patent: US2009/124666, 2009, A1. Location in patent: Page/Page column 25-26
