Synthesis
5-Bromo-2-fluorophenol (13.0 g, 68.1 mmol) and iodomethane (19.3 g, 136 mmol) were dissolved in DMF (120 mL) and potassium carbonate (18.8 g, 136 mmol) was added. The reaction mixture was stirred at room temperature for 65 hours. After completion of the reaction, water (150 mL) was added to the reaction solution and extracted with ethyl acetate (100 mL x 1,50 mL x 2). The organic layers were combined, dried with anhydrous magnesium sulfate and concentrated under reduced pressure to give a light yellow oily crude product (29.0 g). The crude product was purified by silica gel column chromatography (eluent: hexane/ethyl acetate=10:1) to afford 5-bromo-2-fluoroanisole (14.2 g, yield: quantitative) in colorless oily form. The structure of the product was confirmed by 1H-NMR (400 MHz, CDCl3) and 19F-NMR (376 MHz, CDCl3): 1H-NMR δ 3.88 (s, 3H), 6.95 (dd, J = 8.6 and 10.8 Hz, 1H), 7.02 (ddd, J = 2.2,4.2 and 8.6 Hz, 1H), 7.08 (dd. J = 2.2 and 7.6 Hz, 1H); 19F-NMR δ -137 (s, 1F).
References
[1] Patent: US2016/24110, 2016, A1. Location in patent: Paragraph 0452; 0453
[2] Patent: WO2006/76246, 2006, A2. Location in patent: Page/Page column 87
[3] Patent: US2010/227894, 2010, A1. Location in patent: Page/Page column 28
[4] Patent: US2007/3539, 2007, A1. Location in patent: Page/Page column 71
