Ethanol → Methyl 1-benzyl-1H-pyrazole-4-carboxylate

HRID 2261296Notes

Reaction equation

HRID 2261296 reaction equation
[Na].[CH3:2][O:3][CH:4]([O:12]C)[C:5](=[CH:10]O)[C:6](OC)=O.C(O)C.Cl.Cl.[CH2:19]([NH:26][NH2:27])[C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1>O>[CH2:19]([N:26]1[CH:10]=[C:5]([C:4]([O:3][CH3:2])=[O:12])[CH:6]=[N:27]1)[C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1

Participants

5

Reactant 3

HCID 702EthanolHCID 146540Benzylhydrazine dihydrochlorideHCID 86612677Methyl 2-(dimethoxymethyl)-3-hydroxyacrylate sodium salt

Product 1

HCID 45073393Methyl 1-benzyl-1H-pyrazole-4-carboxylateYield 36.4%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
70 °C

Procedure

18.68 g of methyl 2-(dimethoxymethyl)-3-hydroxyacrylate sodium salt was added to 80 ml of ethanol, and 18.39 g of benzylhydrazine dihydrochloride was added. The mixture was stirred at 70° C. for 7 hours and then cooled to room temperature. After 100 ml of water was added, the mixture was concentrated to 100 ml under reduced pressure. The concentrated solution was extracted with ethyl acetate. The organic layer was washed with aqueous saturated sodium chloride, dried over anhydrous sodium sulfate and then concentrated under reduced pressure. The residue was subjected to silica gel column chromatography to obtain 7.39 g of methyl 1-benzyl-1H-pyrazole-4-carboxylate.

Workup

  1. additionwas added
  2. temperaturecooled to room temperature
  3. concentrationthe mixture was concentrated to 100 ml under reduced pressure
  4. extractionThe concentrated solution was extracted with ethyl acetate
  5. washThe organic layer was washed with aqueous saturated sodium chloride
  6. dry with materialdried over anhydrous sodium sulfate
  7. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-64721635334d4e39b7e9fa62028ec960
Source dataset
uspto-grants-2010_12
Patent number
US07846956B2

Reaction notes

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