反应详情

2.0 g of N′-{2-fluoro-4-methyl-5-(2,2,2-trifluoroethylthio)phenyl}acetohydrazide was dissolved in 100 mL of tetrahydrofuran, 0.95 g of malonyl chloride was added under cooling with ice, stirring was carried out under cooling with ice for one hour, and then stirring was carried out under reflux with heating for 5 hours. Then, the solvent was distilled off under reduced pressure, and the obtained crystals were washed with isopropyl ether to obtain 1.74 g of 1-acetyl-2-{2-fluoro-4-methyl-5-(2,2,2-trifluoroethylthio)phenyl}pyrazolidine-3,5-dione.

1. temperatureunder cooling with ice
2. temperatureunder cooling with ice for one hour
3. stirringstirring
4. temperatureunder reflux
5. temperaturewith heating for 5 hours
6. distillationThen, the solvent was distilled off under reduced pressure
7. washthe obtained crystals were washed with isopropyl ether