反应详情

A mixture of 44 ml (0.3 mol) of ethyl trifluoroacetoacetate and 33 mL (335.4 mmol) of phenylhydrazine in 60 ml of methanol containing 6 ml of conc. HCl solution was refluxed with stirring for 1.5 hours. After adding activated charcoal with stirring, the hot mixture was filtered. The residue was washed with methanol (2×70 ml), diluted with water, and the resulting white solid was filtered. The solid was washed with hexane and dried to afford 54.3 g (79%) of 1-phenyl-3-trifluoromethyl-5-hydroxypyrazole as a pale solid.

1. temperaturewas refluxed
2. stirringwith stirring
3. filtrationthe hot mixture was filtered
4. washThe residue was washed with methanol (2×70 ml)
5. additiondiluted with water
6. filtrationthe resulting white solid was filtered
7. washThe solid was washed with hexane
8. customdried