Ethyl 2-formyl-3-oxopropanoate → 1-(5-carboxy-2-methyl-phenyl)-1H-pyrazole-4-carboxylic acid ethyl ester

HRID 491851

Reaction equation

HRID 491851 reaction equation
[CH2:1]([O:3][C:4](=[O:10])[CH:5]([CH:8]=O)[CH:6]=O)[CH3:2].Cl.[NH:12]([C:14]1[CH:15]=[C:16]([CH:20]=[CH:21][C:22]=1[CH3:23])[C:17]([OH:19])=[O:18])[NH2:13]>CCO>[CH2:1]([O:3][C:4]([C:5]1[CH:8]=[N:13][N:12]([C:14]2[CH:15]=[C:16]([C:17]([OH:19])=[O:18])[CH:20]=[CH:21][C:22]=2[CH3:23])[CH:6]=1)=[O:10])[CH3:2]

Participants

4

Reactant 2

HCID 11029955Ethyl 2-formyl-3-oxopropanoateHCID 567775083-Hydrazino-4-methylbenzoic acid hydrochloride

Product 1

HCID 575597081-(5-carboxy-2-methyl-phenyl)-1H-pyrazole-4-carboxylic acid ethyl esterYield 68%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent2×

Procedure

A solution of 2-formyl-3-oxo-propionic acid ethyl ester (S. H. Bertz et al., J. Org. Chem., 1982, 47, 2216) (1.44 g, 10 mmol) in EtOH (10 mL) was cooled in an ice bath. A slurry of 3-hydrazino-4-methyl-benzoic acid hydrochloride (2.02 g, 10 mmol) in EtOH (50 mL) was added and the reaction was stirred overnight. The EtOH was removed under reduced pressure and the residue partitioned between water and CH2Cl2. The layers were separated and the organic layer washed with brine. The organic layer was dried over Na2SO4, filtered, and concentrated. Hexanes were added and the solution concentrated. The resulting solid was collected by vacuum filtration, washed with hexanes and dried under vacuum to provide 1-(5-carboxy-2-methyl-phenyl)-1H-pyrazole-4-carboxylic acid ethyl ester (1.86 g, 68%) as a yellow solid: ESI MS m/z 275 [C14H14N2O4+H]+.

Workup

  1. customThe EtOH was removed under reduced pressure
  2. customthe residue partitioned between water and CH2Cl2
  3. customThe layers were separated
  4. washthe organic layer washed with brine
  5. dry with materialThe organic layer was dried over Na2SO4
  6. filtrationfiltered
  7. concentrationconcentrated
  8. additionHexanes were added
  9. concentrationthe solution concentrated
  10. filtrationThe resulting solid was collected by vacuum filtration
  11. washwashed with hexanes
  12. customdried under vacuum

Sources & evidence

ORD record
ord-c22620a1782542e7943f04f163d8a864
Source dataset
uspto-grants-2009_05
Patent number
US07531560B2

Linked notes

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