反应详情

20 g (184.9 mmoles) of phenylhydrazine and 4 ml of concentrated hydrochloric acid were added to a solution of 34.1 g (184.9 mmoles) of ethyl trifluoroacetoacetate dissolved in 500 ml of ethanol. The mixture was refluxed for 1 hour with heating, to give rise to a reaction. After the completion of the reaction, the reaction mixture was subjected to vacuum distillation to remove the most part of the solvent contained therein. The residue was mixed with water to precipitate crystals. The crystals were collected by filtration, washed with water until the filtrate became neutral, and dried to obtain 37.1 g (yield: 87.9%) of 1-phenyl-3-trifluoromethyl-1H-pyrazol-5-ol as ocherous crystals.

1. temperatureThe mixture was refluxed for 1 hour
2. temperaturewith heating
3. customto give rise
4. customto a reaction
5. customAfter the completion of the reaction
6. distillationthe reaction mixture was subjected to vacuum distillation
7. customto remove the most part of the solvent
8. additionThe residue was mixed with water
9. customto precipitate crystals
10. filtrationThe crystals were collected by filtration
11. washwashed with water until the filtrate
12. customdried