反应详情

温度

70 °C

A solution of 32 g of pyrido[2,3-B][1,4]benzodioxin in 100 ml of glacial acetic acid is treated with 36 g of 40% peracetic acid in acetic acid in four equal portions. After the fourth portion is added, the mixture is heated at 70° C. for 10 minutes. Another 4 g of 40% peracetic acid in acetic acid is added and the temperature is maintained at 70° C. for 10 minutes and then heated to reflux for 10 minutes. The mixture is concentrated at reduced pressure, 100 ml of isopropanol is added and the mixture is concentrated again. The resulting oil is dissolved in 700 ml of dichloromethane and the organic layer is washed with excess cold 25% sodium hydroxide solution. The organic layer is dried and evaporated to yield the pyrido[2,3-B][1,4]-benzodioxin 1-oxide, mp 223°-226° C. after recrystallization from acetonitrile.

1. additionAfter the fourth portion is added
2. temperaturethe temperature is maintained at 70° C. for 10 minutes
3. temperatureheated
4. temperatureto reflux for 10 minutes
5. concentrationThe mixture is concentrated at reduced pressure, 100 ml of isopropanol
6. additionis added
7. concentrationthe mixture is concentrated again
8. dissolutionThe resulting oil is dissolved in 700 ml of dichloromethane
9. washthe organic layer is washed with excess cold 25% sodium hydroxide solution
10. customThe organic layer is dried
11. customevaporated