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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 240805Generated: October 25, 2026

Ethyl Acetoacetate → Ethyl 5-methyl-1-phenyl-1H-pyrazole-4-carboxylate

https://huagongshe.com/reaction/240805

Reaction equation

Participants

RoleNameHCIDCharge
ReactantEthyl AcetoacetateHCID 8868—
ReactantPhenylhydrazine hydrochlorideHCID 60962—
ReactantDimethylformamide dimethyl acetalHCID 78373—
SolventEthanolHCID 702—
ProductEthyl 5-methyl-1-phenyl-1H-pyrazole-4-carboxylateHCID 9668087.6%

Reaction Conditions

Temperature120 °C

Reaction Steps

A mixture of ethyl acetoacetate (1.5 g, 11.5 mmol) and dimethylformamide dimethyl acetal (1.68 mL, 12.7 mmol) was stirred at 120° C. for 2 hours. The reaction solution was cooled to room temperature, and a solution of phenyl hydrazine hydrochloride (1.67 g, 11.5 mmol) in ethanol (30 mL) was then added thereto. The obtained mixture was stirred at 80° C. for 2.5 hours. The reaction solution was cooled to room temperature, and it was then concentrated under reduced pressure. The residue was purified with a fractionation purification apparatus (Biotage, ethyl acetate:hexane=1:19-3:7), so as to obtain the title compound (2.32 g, 87%) in the form of a yellow oily product.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS08648103B2
Source datasetuspto-grants-2014_02
ORD IDord-56649bbc9a974d688e5688716682c800
Source noteuspto-grants-2014_02