反应详情

11.2 g (0.1 mole) of 1,3-dimethyl-5-pyrazolone and 9.6 g (0.13 mole) of calcium hydroxide were suspended in 165 ml of isopropanol, and with stirring, the suspension was heated under reflux for 30 minutes. The reaction mixture was cooled, and 22.4 g (0.1 mole) of 2,4-dichloro-3-methyl-benzoyl chloride was added dropwise. After the addition, the mixture was heated under reflux for 10 hours. The solvent was distilled off from the reaction mixture, and 40 ml of water was added. The mixture was acidified with 65 ml of 2 N hydrochloric acid, and extracted with 100 ml of chloroform twice. The extracts were washed with water, and dried over magnesium sulfate. The solvent was distilled off, and the residue was recrystallized from toluene to give 14.9 g of colorless crystals (yield 49.8%; melting point 148.9°-149.5° C.).

1. temperaturethe suspension was heated
2. temperatureunder reflux for 30 minutes
3. temperatureThe reaction mixture was cooled
4. additionAfter the addition
5. temperaturethe mixture was heated
6. temperatureunder reflux for 10 hours
7. distillationThe solvent was distilled off from the reaction mixture, and 40 ml of water
8. additionwas added
9. extractionextracted with 100 ml of chloroform twice
10. washThe extracts were washed with water
11. dry with materialdried over magnesium sulfate
12. distillationThe solvent was distilled off
13. customthe residue was recrystallized from toluene