反应详情

A mixture of 4-oxo-3-propionyl-hexanoic acid ethyl ester (15 g, 70 mmol) and hydrazine hydrate (3.5 mL, 71 mmol) in absolute ethanol (150 mL) was refluxed for 16 h. Solvent was removed under reduced pressure and the residue was purified by silica gel column chromatography (methanol in methylene chloride) to provide (3,5-diethyl-1H-pyrazol-4-yl)-acetic acid ethyl ester as yellow oil (11 g, 51 mmol).

1. temperaturewas refluxed for 16 h
2. customSolvent was removed under reduced pressure
3. customthe residue was purified by silica gel column chromatography (methanol in methylene chloride)