反应详情

Potassium carbonate (2.43 g, 17.6 mmol) and methyl iodide (1.3 ml, 20.9 mmol) were added to a solution of the 1-[8-(tert-butyl)-3,4-dihydro-2H-1,4-benzoxazin-6-yl]-1-ethanone (3.73 g, 16.0 mmol) in dimethylformamide (35 ml) under a nitrogen atmosphere, and the mixture was stirred at room temperature for 1 day. The solvent was distilled off under reduced pressure, ethyl acetate was added to the residue and the mixture was washed with water (twice) and brine in that order. After drying over anhydrous magnesium sulfate, the solvent was distilled off under reduced pressure. The residue was subjected to silica gel chromatography (Wakogel-C200,60 g) and then fractionated with 2% ethyl acetate-toluene to yield the title compound (2.61 g, 66.0% yield) as bright golden yellow crystals.

1. distillationThe solvent was distilled off under reduced pressure, ethyl acetate
2. additionwas added to the residue
3. washthe mixture was washed with water (twice) and brine in that order
4. dry with materialAfter drying over anhydrous magnesium sulfate
5. distillationthe solvent was distilled off under reduced pressure