反应详情

In 15 ml of toluene were dissolved 0.5 g of 6-cyano-3,4-dihydro-2,2-dimethyl-2H-1,4-benzoxazine, 0.33 g of cyclohexane-1,2-dione and a catalytic amount of p-toluenesulfonic acid and using a Dean-Stark trap, the solution was refluxed under heating for 4 hours. After cooling, the reaction mixture was washed with saturated aqueous sodium hydrogen carbonate solution and aqueous sodium chloride solution and dried over anhydrous magnesium sulfate and the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography and the resulting crude crystals were washed with ethanol to give 0.5 g of 6-cyano-3,4-dihydro-2,2-dimethyl-4-(6-oxo-1-cyclohexen-1-yl)-2H-1,4-benzoxazine.

1. temperaturethe solution was refluxed
2. temperatureunder heating for 4 hours
3. temperatureAfter cooling
4. washthe reaction mixture was washed with saturated aqueous sodium hydrogen carbonate solution and aqueous sodium chloride solution
5. dry with materialdried over anhydrous magnesium sulfate
6. distillationthe solvent was distilled off under reduced pressure
7. customThe residue was purified by silica gel column chromatography
8. washthe resulting crude crystals were washed with ethanol