反应详情

To a mixture of 3-(4,4-dimethyl-2-oxo-1,4-dihydro-2H-3,1-benzoxazin-6-yl)-5-fluorobenzonitrile (0.5 g, 1.7 mmol) and sodium acetate (0.2 g, 2.4 mmol) in acetic acid (5 mL) was added, at room temperature under nitrogen, bromine (0.12 mL, 2.34 mmol). The reaction mixture was stirred for 20 hours and then poured into ice water (30 mL). The precipitate was collected on a filter and washed with water (3×5 mL) to yield 3-(8-bromo-4,4-dimethyl-2-oxo-1,4-dihydro-2H-3,1-benzoxazin-6-yl)-5-fluorobenzonitrile as an off-white solid (0.48 g, 75%): mp 216-217° C.; 1H-NMR (DMSO-d6) δ 9.78 (s, 1H), 8.18 (t, 1H, J=1.6 Hz), 8.02-8.08 (m, 2H), 7.81 (m, 1H), 7.75 (d, 1H, J=1.8 Hz), 1.66 (s, 6H). MS (ESI) m/z 373, 375 [M−H]−.

1. additionwas added, at room temperature under nitrogen
2. customThe precipitate was collected on
3. filtrationa filter
4. washwashed with water (3×5 mL)