反应详情

In 22 ml. of dry dioxane is dissolved 2.24 g. of 1,3-dimethyl-5-pyrazolone and then 2.96 g. of calcium hydroxide is added thereto. 3.71 g. of p-nitrobenzoyl chloride is added dropwise thereto while stirring at room temperature. After completion of the dropwise addition, the mixture is heated under reflux for 1 hour. After completion of the reaction, the reaction mixture is allowed to cool and then 40 ml. of a 2N hydrochloric acid solution is added thereto. Crystalline substances thus separated are recovered by filtration and washed with water to give 4.38 g. of crude crystals. This product is recrystallized from methanol to give 3.62 g. of the desired product as pale yellow columns having a melting point of 234°-235° C. Yield 69.3%.

1. additionAfter completion of the dropwise addition
2. temperaturethe mixture is heated
3. temperatureunder reflux for 1 hour
4. customAfter completion of the reaction
5. temperatureto cool
6. customCrystalline substances thus separated
7. filtrationare recovered by filtration
8. washwashed with water
9. customto give 4.38 g
10. customThis product is recrystallized from methanol
11. customto give 3.62 g