HCID 23402490, compound → 4-amino-3-cyclopentyl-1H-pyrazole-5-carboxamide

HRID 1063813Notes

Reaction equation

HRID 1063813 reaction equation
[CH:1]1([C:6]2[NH:10][N:9]=[C:8]([C:11]([NH2:13])=[O:12])[C:7]=2[N+:14]([O-])=O)[CH2:5][CH2:4][CH2:3][CH2:2]1>[Pd].C(O)C>[NH2:14][C:7]1[C:8]([C:11]([NH2:13])=[O:12])=[N:9][NH:10][C:6]=1[CH:1]1[CH2:5][CH2:4][CH2:3][CH2:2]1

Participants

4

Reactant 1

HCID 23402490HCID 23402490, compound

Product 1

HCID 234024844-amino-3-cyclopentyl-1H-pyrazole-5-carboxamideYield 103%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 702EthanolSolvent

Procedure

5-cyclopentyl-4-nitro-1H-pyrazol-3-carboxylic acid amide (4.48 g, 20 mmol) and 10% palladium on carbon (800 mg) in ethanol (50 ml) were stirred under hydrogen (50 psi) at room temperature for 18 hours. The reaction mixture was filtered through arbocel and the solid was washed with ethanol (50 ml), methanol (50 ml), dichloromethane (50 ml), and ethyl acetate (50 ml). The filtrate was concentrated under reduced pressure and the residue was purified by flash column chromatography on silica gel eluting with dichloromethane:methanol (9:1, by volume) to give 4-amino-5-cyclopentyl-1H-pyrazol-3-carboxylic acid amide (4.0 g) as an off-white solid which was a mixture of rotamers. 1H NMR (400 MHz, DMSO-D6): δ=12.20-12.31 (0.75H, brs), 11.78-11.87 (0.25H, brs), 7.02-7.18 (1.5H, brs), 6.80-6.93 (0.5H, brs), 4.22-4.56 (2H, 2×brs), 2.92-3.02 (1.96 (2H, m), 1.48-1.78 (6H, 2×m) ppm. LRMS (electrospray): m/z [M−H]+ 193. Anal. Found C, 56.12; H, 7.39; N, 27.55. C9H14N4O. 0.2 mol acetone requires C, 56.01; H, 7.44; N, 27.22%.

Workup

  1. filtrationThe reaction mixture was filtered through arbocel
  2. washthe solid was washed with ethanol (50 ml), methanol (50 ml), dichloromethane (50 ml), and ethyl acetate (50 ml)
  3. concentrationThe filtrate was concentrated under reduced pressure
  4. customthe residue was purified by flash column chromatography on silica gel eluting with dichloromethane:methanol (9:1, by volume)

Sources & evidence

ORD record
ord-627fe34d89f34a0e95d28b5f2704e505
Source dataset
uspto-grants-2005_11
Patent number
US06967204B2

Reaction notes

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