4-nitro-1H-pyrazole → HCID 178471961, compound

HRID 1904268Notes

Reaction equation

HRID 1904268 reaction equation
[N+:1]([C:4]1[CH:5]=[N:6][NH:7][CH:8]=1)([O-])=O.[C:9]([C:12](=[CH:18]OCC)[C:13]([O:15][CH2:16][CH3:17])=[O:14])(=[O:11])[CH3:10]>C(O)C.[Pd]>[C:9]([C:12](=[CH:18][NH:1][C:4]1[CH:5]=[N:6][NH:7][CH:8]=1)[C:13]([O:15][CH2:16][CH3:17])=[O:14])(=[O:11])[CH3:10]

Participants

5

Reactant 2

HCID 163764-nitro-1H-pyrazoleHCID 97734Butanoic acid, 2-(ethoxymethylene)-3-oxo-, ethyl ester

Product 1

HCID 178471961HCID 178471961, compoundYield 69%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 702EthanolSolvent

Procedure

A solution of 4-nitropyrazole (5.6 g, 50 mmol)in ethanol (200 ml) was hydrogenated over 10% palladium on charcoal (0.5 g) at room temperature and pressure for 3.5 h. The catalyst was filtered off and ethyl 2-acetyl-3-ethoxyacrylate (9.3 g, 50 mmol) was added to the solution under nitrogen. After 5 min, the solution was evaporated in vacuo and the residual solid was recrystallised from ethyl acetate/pentane (charcoal) to give the title compound (7.7 g, 69%), m.p. 126°-128° C. Found: C, 49.96; H, 6.28; N, 17.34%. C10H13N3O3.H2O requires C, 49.78; H, 6.27; N, 17.41%.

Workup

  1. filtrationThe catalyst was filtered off
  2. waitAfter 5 min
  3. customthe solution was evaporated in vacuo
  4. customthe residual solid was recrystallised from ethyl acetate/pentane (charcoal)

Sources & evidence

ORD record
ord-903721ab4f4d4477a3fb33e00f6d988e
Source dataset
uspto-grants-1989_06
Patent number
US04837238

Reaction notes

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