methyl 3-nitro-1H-pyrazole-5-carboxylate → HCID 178498460, compound

HRID 550614Notes

Reaction equation

HRID 550614 reaction equation
[CH3:1][O:2][C:3]([C:5]1[CH:9]=[C:8]([N+:10]([O-])=O)[NH:7][N:6]=1)=[O:4]>C1COCC1.C(O)(=O)C.[Pd]>[CH3:1][O:2][C:3]([C:5]1[CH:9]=[C:8]([NH2:10])[NH:7][N:6]=1)=[O:4]

Participants

5

Reactant 1

HCID 135452337methyl 3-nitro-1H-pyrazole-5-carboxylate

Product 1

HCID 178498460HCID 178498460, compound

Reagents, catalysts & solvents 3

HCID 23938PalladiumCatalystHCID 176Acetic AcidSolventHCID 8028TetrahydrofuranSolvent

Procedure

5-Nitro-3-pyrazole-carboxylic acid methyl ester (22.35 g, 130.61 mmol) is dissolved in each 160 mL THF und glacial acetic acid. Then, Pd—C (10%, 4.36 g) are added and the reaction is stirred for 6 days under hydrogen atmosphere at RT. Then, the mixture is filtered over celite and the solvent is removed under vacuum. The crude material is dissolved in methylene chloride (800 mL) and sodium hydrogen carbonate (200 g) are added, filtered and the solvent is again removed under vacuum. This procedure is repeated until the acetic acid smell is lost. 5-Amino-3-pyrazole-carboxylic acid methyl ester is isolated in high yields (16.91 g, 91.7%)

Workup

  1. filtrationThen, the mixture is filtered over celite
  2. customthe solvent is removed under vacuum
  3. dissolutionThe crude material is dissolved in methylene chloride (800 mL)
  4. additionsodium hydrogen carbonate (200 g) are added
  5. filtrationfiltered
  6. customthe solvent is again removed under vacuum

Sources & evidence

ORD record
ord-c3a8f14f60a348749bfc767c12d7a5f4
Source dataset
uspto-grants-2011_05
Patent number
US07947689B2

Reaction notes

Loading…