反应详情

A solution of ethyl 3-hydroxy-1H-pyrazole-4-carboxylate (625 mg, 4.00 mmol) in 10% NaOH (aq) (20 mL) and EtOH (10 mL) was heated under reflux for 20 h. EtOH was removed under reduced pressure. The residue was diluted with 10 mL of H2O and acidified with 4 N HCl. The precipitates were filtered to afford the titled compound as a white solid (460 mg), which was used without further purification.

1. temperatureunder reflux for 20 h
2. customEtOH was removed under reduced pressure
3. additionThe residue was diluted with 10 mL of H2O
4. filtrationThe precipitates were filtered