反应详情

温度

0 °C

To 131A (1.83 g, 9.2 mmol) in anhydrous CH2Cl2 (30 mL) at 0° C. was added MeOH (2.24 mL) and 4.0 N HCl in dioxane (9.2 mL). The mixture was stirred at 0° C. for 30 min and then at rt for 4.0 h. Solvent was removed to give methyl 2-(3-(difluoromethoxy)-phenyl)-2-hydroxyacetimidate HCl salt. To this salt in CH2Cl2 (10 mL) was added H2O (10 mL). The mixture was stirred at rt for 30 min, then extracted with CH2Cl2 (2×50 mL). The combined organic extracts were dried and concentrated. The crude prouduct was purified by silica gel chromatography to give 131B (700 mg, 33% yield) as a viscous oil. 1H NMR (400 MHz, CDCl3) δ ppm 3.70 (s, 3H) 5.22 (s, 1H) 6.82 (t, J=74.04 Hz, 1H) 7.09 (dd, J=7.91, 2.20 Hz, 1H) 7.23 (s, 1H) 7.28-7.34 (m, 1H) 7.38 (t, J=7.91 Hz, 1H).

1. waitat rt for 4.0 h
2. customSolvent was removed