Ammonium formate → 4-amino-1-(2-ethoxyethyl)-3-ethyl-1H-pyrazole-5-carboxamide

HRID 1896203

Reaction equation

HRID 1896203 reaction equation
[CH2:1]([O:3][CH2:4][CH2:5][N:6]1[C:10]([C:11]([NH2:13])=[O:12])=[C:9]([N+:14]([O-])=O)[C:8]([CH2:17][CH3:18])=[N:7]1)[CH3:2].C([O-])=O.[NH4+]>C(O)C.[OH-].[Pd+2].[OH-]>[NH2:14][C:9]1[C:8]([CH2:17][CH3:18])=[N:7][N:6]([CH2:5][CH2:4][O:3][CH2:1][CH3:2])[C:10]=1[C:11]([NH2:13])=[O:12]

Participants

5

Reactant 2

HCID 2723923Ammonium formateHCID 577445561-(2-ethoxyethyl)-3-ethyl-4-nitro-1H-pyrazole-5-carboxamide

Product 1

HCID 577445394-amino-1-(2-ethoxyethyl)-3-ethyl-1H-pyrazole-5-carboxamideYield 49.2%

Reagents, catalysts & solvents 2

HCID 9942167Palladium hydroxideCatalystHCID 702EthanolSolvent

Procedure

A mixture of 1-(2-ethoxyethyl)-3-ethyl-4-nitro-1H-pyrazole-5-carboxamide from step 1 (5.70 g, 22 mmol) and palladium hydroxide (1.0 g) in ethanol (110 mL) was treated with ammonium formate (7.01 g, 111 mmol) in four unequal portions at about 10 minute intervals. The resulting mixture was heated under reflux for two hours and then cooled. The mixture was filtered through celite and concentrated. The resulting residue was purified by column chromatography on silica gel using a mixture of ethyl acetate and hexane as the eluent to provide 2.45 g of the title compound. 1H NMR (400 MHz, CDCl3): δ 1.17 (t, 3 H), 1.21-1.32 (m, 3 H), 2.60 (q, 2 H), 3.53 (q, 2 H), 3.79-3.95 (m, 2 H), 4.38-4.52 (m, 2 H). MS (ESI) m/z 227.

Workup

  1. temperatureThe resulting mixture was heated
  2. temperatureunder reflux for two hours
  3. temperaturecooled
  4. filtrationThe mixture was filtered through celite and
  5. concentrationconcentrated
  6. customThe resulting residue was purified by column chromatography on silica gel using
  7. additiona mixture of ethyl acetate and hexane as the eluent

Sources & evidence

ORD record
ord-b28515ed3cb94be1a17cff64f6fdab36
Source dataset
uspto-grants-2013_08
Patent number
US08518956B2

Linked notes

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