Ethyl Acetoacetate → ethyl 3-methyl-1H-pyrazole-4-carboxylate

HRID 2067950Notes

Reaction equation

HRID 2067950 reaction equation
[C:1]([O:7][CH2:8][CH3:9])(=[O:6])[CH2:2][C:3]([CH3:5])=O.COC(OC)[N:13]([CH3:15])C.O.[NH2:19]N>CCO>[CH2:8]([O:7][C:1]([C:2]1[CH:15]=[N:13][NH:19][C:3]=1[CH3:5])=[O:6])[CH3:9]

Participants

5

Reactant 3

HCID 8868Ethyl AcetoacetateHCID 24654Hydrazine hydrate (1:1)HCID 78373Dimethylformamide dimethyl acetal

Product 1

HCID 227598ethyl 3-methyl-1H-pyrazole-4-carboxylate

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A mixture of ethyl acetoacetate (8.0 mL, 63 mmol) and dimethylformamide-dimethylacetal (8.3 mL, 63 mmol) is heated to reflux for 1 hour. The reaction mixture is cooled to room temperature and diluted with EtOH (70 mL). Hydrazine hydrate (3.0 mL, 63 mmol) is then added and the reaction is heated at 80° C. for 2 hours. The resultant solution is cooled to room temperature and concentrated in vacuo to afford crude 5-methyl-1H-pyrazole-4-carboxylic acid ethyl ester which is used without further purification.

Workup

  1. temperatureis heated
  2. temperatureto reflux for 1 hour
  3. temperaturethe reaction is heated at 80° C. for 2 hours
  4. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-16c55be14ef14d909a9cceb8160c6c80
Source dataset
uspto-grants-2012_10
Patent number
US08293917B2

Reaction notes

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