反应详情

To a solution of 8-fluoro-4,4-dimethyl-dihydro-benzo[d][1,3]oxazin-2-one (0.15 g, 0.77 mmol) in acetic acid (5 mL) was added dropwise a solution of bromine (0.37 g, 2.31 mmol) in acetic acid (5 mL) under nitrogen at rt. After stirring for 10 minutes, the mixture was concentrated and the residue obtained was purified by a silica gel column (hexane:ethyl acetate/4:1) to afford 6-bromo-8-fluoro-4,4-dimethyl-dihydro-benzo[d][1,3]oxazin-2-one as an off-white solid (0.176 g, 84%) which was used in next step without further purification.

1. concentrationthe mixture was concentrated
2. customthe residue obtained
3. customwas purified by a silica gel column (hexane:ethyl acetate/4:1)