Acetic Acid → 4-(5-Amino-3-tert-butyl-pyrazol-1-yl)-benzoic acid

HRID 1174832

Reaction equation

HRID 1174832 reaction equation
[CH3:1][C:2]([CH3:9])([CH3:8])[C:3](=O)[CH2:4][C:5]#[N:6].[NH:10]([C:12]1[CH:20]=[CH:19][C:15]([C:16]([OH:18])=[O:17])=[CH:14][CH:13]=1)[NH2:11].C(O)(=O)C>CCO.C1COCC1>[NH2:6][C:5]1[N:10]([C:12]2[CH:13]=[CH:14][C:15]([C:16]([OH:18])=[O:17])=[CH:19][CH:20]=2)[N:11]=[C:3]([C:2]([CH3:9])([CH3:8])[CH3:1])[CH:4]=1

Participants

5

Reactant 3

HCID 176Acetic AcidHCID 120894-Hydrazinobenzoic acidHCID 108871Pentanenitrile, 4,4-dimethyl-3-oxo-

Product 1

HCID 9746884-(5-Amino-3-tert-butyl-pyrazol-1-yl)-benzoic acidYield 99%

Reagents, catalysts & solvents 1

HCID 21873804Tetrahydrofuran ethanolSolvent

Procedure

A mixture of 4,4-dimethyl-3-oxo-pentanenitrile (4.52 g, 36.15 mmol), 4-hydrazinobenzoic acid (5.00 g, 32.86 mmol), and acetic acid (2 mL) in EtOH/THF (1:1) was refluxed for 16 h. After cooling, the solvent was concentrated at reduced pressure, and the crude was re-dissolved in EtOAc. The organic layer was washed with aqueous saturated Na2CO3 solution and brine, dried over MgSO4, filtered, and concentrated to half its volume. The resulting residue was filtered, and the solids were washed with cold EtOAc and dried under high vacuum to afford the title compound as a white solid (8.4 g, 99%). 1H-NMR (DMSO-d6) δ 12.91 (s, 1H), 7.99 (d, J=6.0 Hz, 2H), 7.75 (d, J=9.0 Hz, 2H), 5.42 (s, 1H), 5.39 (s, 2H), 1.21 (s, 9H); MS LC-MS [M+H]+=260, RT=1.83 min.

Workup

  1. temperaturewas refluxed for 16 h
  2. temperatureAfter cooling
  3. concentrationthe solvent was concentrated at reduced pressure
  4. dissolutionthe crude was re-dissolved in EtOAc
  5. washThe organic layer was washed with aqueous saturated Na2CO3 solution and brine
  6. dry with materialdried over MgSO4
  7. filtrationfiltered
  8. concentrationconcentrated to half its volume
  9. filtrationThe resulting residue was filtered
  10. washthe solids were washed with cold EtOAc
  11. customdried under high vacuum

Sources & evidence

ORD record
ord-ee33ca7f0c31475db118e4b5cef513e0
Source dataset
uspto-grants-2010_11
Patent number
US07838524B2

Linked notes

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