Ethanol → Ethyl 5-amino-1-methyl-1H-pyrazole-4-carboxylate

HRID 1731268Notes

Reaction equation

HRID 1731268 reaction equation
[CH3:1][NH:2][NH2:3].[CH2:4]([O:6][C:7](=[O:15])[C:8](=COCC)[C:9]#[N:10])[CH3:5].[CH2:16](O)C>>[NH2:10][C:9]1[N:3]([CH3:16])[N:2]=[CH:1][C:8]=1[C:7]([O:6][CH2:4][CH3:5])=[O:15]

Participants

4

Reactant 3

HCID 702EthanolHCID 6061MethylhydrazineHCID 789432-Propenoic acid, 2-cyano-3-ethoxy-, ethyl ester

Product 1

HCID 271299Ethyl 5-amino-1-methyl-1H-pyrazole-4-carboxylateYield 35%

Procedure

Methylhydrazine (25 grams, 0.54 mole) and ethyl(ethoxymethylene)cyanoacetate (92 grams, 0.54 mole) were combined in 150 ml. of ethanol and refluxed for about 16 hours. The reaction mixture was then cooled and poured over ice water, and the resulting precipitated product was collected by filtration and dried. The mother liquor was extracted with chloroform, washed with saturated brine, and dried using sodium sulfate and filter paper. Solvent was removed in vacuo. Both groups of crystallized product were recrystallized from ethanol, yielding 32.3 grams (35%) of 5-amino-1-methyl-1H-pyrazole-4-carboxylic acid, ethyl ester, mp=99°-100° C.

Workup

  1. temperatureThe reaction mixture was then cooled
  2. customthe resulting precipitated product
  3. filtrationwas collected by filtration
  4. customdried
  5. extractionThe mother liquor was extracted with chloroform
  6. washwashed with saturated brine
  7. customdried
  8. filtrationfilter paper
  9. customSolvent was removed in vacuo
  10. customBoth groups of crystallized product were recrystallized from ethanol

Sources & evidence

ORD record
ord-efa966af0e794bd18498fab1d888adf4
Source dataset
uspto-grants-1986_11
Patent number
US04620865

Reaction notes

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