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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1289824Generated: November 2, 2026

Water → 3H-Pyrazol-3-one, 2,4-dihydro-2-methyl-5-phenyl-

https://huagongshe.com/reaction/1289824

Reaction equation

Participants

RoleNameHCIDCharge
ReactantWaterHCID 962—
ReactantMethylhydrazineHCID 6061—
ReactantEthyl benzoylacetateHCID 7170—
Solvent1,4-DioxaneHCID 31275—
Product3H-Pyrazol-3-one, 2,4-dihydro-2-methyl-5-phenyl-HCID 142562—

Reaction Conditions

Temperature500 °C

Reaction Steps

To a mixture of 17.3 ml of ethyl benzoylacetate and 10 ml of water heated to 500° C. was added dropwise 5.3 ml of methyl-hydrazine over a period of 10 minutes (temperature rose to 70° C.) and the resulting mixture was heated at 60° C. for 2 hours. After adding 10 ml of dioxane the mixture was stirred at 55°-65° C. overnight, filtered, and the white solid was washed with water and dried in vacuo (P2O5) to afford 13.23 g of 2,4-dihydro-2-methyl-5-phenyl-3H-pyrazol-3-one (Formula III: R1 =CH3 ; R2 =Ph; R3 =H) as a white solid, m.p. 207° C.(d)

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS05750550
Source datasetuspto-grants-1998_05
ORD IDord-92343ace25f449868aa21d5724860f39
Source noteuspto-grants-1998_05