Chloroacetyl chloride → 6-Bromo-2H-1,4-benzoxazin-3(4H)-one

Participants

Reaction Conditions

Reaction Steps

To a mixture of 2-amino-4-bromophenol (50 g, 266 mmol) and NaHCO3 (67.0 g, 798 mmol) in water (200 mL) and DME (200 mL) was added 2-chloroacetyl chloride (45.1 g, 399 mmol) at 0° C. The mixture was stirred at 15° C. for 0.5 h and then stirred at 80° C. overnight. The mixture was cooled to ambient temperature and quenched with water (400 mL). The precipitate was collected by suction filtration, washed with water (200 mL) and petroleum ether (300 mL) in turn, and dried to give 6-bromo-4H-benzo[1,4]oxazin-3-one (59 g, 97%) as a gray solid. 1H NMR (DMSO-d6, 400 MHz): δ 7.07 (d, J=8.4 Hz, 1H), 7.02 (s, 1H), 6.90 (d, J=8.4 Hz, 1H), 4.59 (s, 2H).

Provenance & Evidence