反应详情

温度

20 °C

10 g of methyl 5-cyano-2,4-dioxo-3-azaspiro[5,5]undecane-1-carboxylate and 5 g of NaOH dissolved in 125 ml of 2:1 ethanol/water are placed in a 250 ml flask equipped with mechanical agitator, thermometer and condenser. The mixture is heated under reflux for 1.5 hours, acidified with 5% HCl to pH 2 and heated under reflux for 3 hours. By cooling to 20° C. a precipitate is formed which is filtered off, washed with water and dried under vacuum. 4.7 g of 2,4-dioxo-3-azaspiro[5,5]undecane are obtained.

1. customare placed in a 250 ml flask
2. customequipped with mechanical agitator
3. temperatureThe mixture is heated
4. temperatureunder reflux for 1.5 hours
5. temperatureheated
6. temperatureunder reflux for 3 hours
7. customis formed which
8. filtrationis filtered off
9. washwashed with water
10. customdried under vacuum