Chloroacetyl chloride → 7-fluoro-3,4-dihydro-2H-1,4-benzoxazin-3-one

Participants

Reaction Steps

To a suspension of 2-amino-5-fluorophenol (Alfa, 15.00 g, 118 mmol), K2CO3 (48.9 g, 354 mmol) and tetrabutyl-ammonium bromide (3.80 g, 11.80 mmol) in MeCN (200 mL) was added 2-chloroacetyl chloride (14.66 g, 130 mmol) dropwise at 0° C. The reaction mixture was warmed to rt and then heated at reflux overnight. The reaction mixture was cooled to ambient temperature and concentrated in vacuo. The solid was collected, washed with water (100 mL) and dried in vacuo to give 7-fluoro-4H-benzo[1,4]oxazin-3-one as a pale solid (17.2 g, 87%). 1H NMR (DMSO-d6, 400 MHz): δ10.71 (s, 1H), 6.84-6.88 (m, 2H), 6.76-6.81 (m, 1H), 4.57 (s, 2H).

Provenance & Evidence