反应详情

Hydroxylamine (10 mL of a 50% solution in water) was added in one portion to a stirred suspension of 3,5-dibromo-4-hydroxybenzonitrile (30 g, 110 mmol) in ethanol (100 mL) at room temperature and the mixture was heated to reflux for 3 hours before cooling back down to room temperature. The solid was filtered, washed with cold ethanol and dried to yield the title compound (25.5 g, 75%) as a colourless powder. 1H NMR δ (ppm) (DMSO-d6): 5.92 (2H, br s), 7.87 (2H, s), 9.69 (1H, br s), 10.19 (1H, br s).

1. temperaturethe mixture was heated
2. temperatureto reflux for 3 hours
3. filtrationThe solid was filtered
4. washwashed with cold ethanol
5. customdried