Water → 1-(3-Nitrophenyl)-3-oxo-2,3-dihydro-1H-pyrazole-4-carboxylic acid

HRID 1814758Notes

Reaction equation

HRID 1814758 reaction equation
C[O:2][C:3]([C:5]1[C:6](=[O:19])[NH:7][N:8]([C:10]2[CH:15]=[CH:14][CH:13]=[C:12]([N+:16]([O-:18])=[O:17])[CH:11]=2)[CH:9]=1)=[O:4].O.[OH-].[Na+]>O1CCOCC1>[N+:16]([C:12]1[CH:11]=[C:10]([N:8]2[CH:9]=[C:5]([C:3]([OH:4])=[O:2])[C:6](=[O:19])[NH:7]2)[CH:15]=[CH:14][CH:13]=1)([O-:18])=[O:17]

Participants

5

Reactant 3

HCID 962WaterHCID 14798Sodium HydroxideHCID 69180302Methyl 2,3-dihydro-1-(3-nitrophenyl)-3-oxo-1H-pyrazole-4-carboxylate

Product 1

HCID 224986871-(3-Nitrophenyl)-3-oxo-2,3-dihydro-1H-pyrazole-4-carboxylic acidYield 62.6%

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Procedure

1-(3-Nitrophenyl)-3-oxo-2,3-dihydro-1H-pyrazole-4-carboxylic acid methyl ester (1.43 g, 0.005 mole) (Taylor A. W. et al, Tetrahedron, 1987, 43 (3), 607-616) in 1,4-dioxane (100 ml) and water (100 ml) was treated with sodium hydroxide (2 g, 0.05 mole) and heated under reflux for 6 hours. The mixture was allowed to cool then concentrated to a small volume in-vacuo, and acidified with concentrated hydrochloric acid. The resulting solid was filtered off and dried in-vacuo to give the title compound as an off-white solid (0.78 g, 60%). M.S. (−ive ion electrospray) m/z 248 ([M−H]−, 25%), 276 (100%).

Workup

  1. temperatureheated
  2. temperatureunder reflux for 6 hours
  3. temperatureto cool
  4. concentrationthen concentrated to a small volume in-vacuo
  5. filtrationThe resulting solid was filtered off
  6. customdried in-vacuo

Sources & evidence

ORD record
ord-9dc4d69e6e0c47fb83e8091c9f0ca3da
Source dataset
uspto-grants-2005_04
Patent number
US06878704B2

Reaction notes

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