反应详情

To a solution of (2-amino-5-bromophenyl)(phenyl)methanone (1 g, 3.6 mmol) in anhydrous THF (15 mL) was added at room temperature under nitrogen methylmagnesium bromide (3M in ether, 3 mL, 9 mmol). After 3 hours, the mixture was treated with a saturated aqueous ammonium sulfate solution (30 mL) and ethyl acetate (50 mL). The organic layer was separated, dried (MgSO4), and evaporated. The residue was then dissolved in anhydrous toluene and treated at ambient temperature under nitrogen with acetylaldehyde (2 mL). After 2 minutes, the solvent was removed and residue was purified by a column chromatography (silica gel, hexane:ethyl acetate/4:1) to afford 6-bromo-2,4-dimethyl-4-phenyl-1,4-dihydro-2H-3,1-benzoxazine as a yellowish solid (0.8 g, 70%): MS (ESI) m/z 318/320 [M+H]+.

1. customThe organic layer was separated
2. dry with materialdried (MgSO4)
3. customevaporated
4. dissolutionThe residue was then dissolved in anhydrous toluene
5. additiontreated at ambient temperature under nitrogen with acetylaldehyde (2 mL)
6. waitAfter 2 minutes
7. customthe solvent was removed
8. customresidue was purified by a column chromatography (silica gel, hexane:ethyl acetate/4:1)