Bromoacetic Acid → 2-(4-nitro-1H-pyrazol-1-yl)acetic acid

HRID 1422904Notes

Reaction equation

HRID 1422904 reaction equation
Br[CH2:2][C:3]([OH:5])=[O:4].[N+:6]([C:9]1[CH:10]=[N:11][NH:12][CH:13]=1)([O-:8])=[O:7].C(=O)([O-])[O-].[K+].[K+]>O1CCCC1>[N+:6]([C:9]1[CH:10]=[N:11][N:12]([CH2:2][C:3]([OH:5])=[O:4])[CH:13]=1)([O-:8])=[O:7]

Participants

5

Reactant 3

HCID 6227Bromoacetic AcidHCID 11430Potassium CarbonateHCID 163764-nitro-1H-pyrazole

Product 1

HCID 12834772-(4-nitro-1H-pyrazol-1-yl)acetic acidYield 78%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

Bromo-acetic acid (1.23 g, 8.84 mmol, 2.0 eq) is added at room temperature to a stirred solution of 4-nitro-1H-pyrazole (500 mg, 4.42 mmol, 1.0 eq) in tetrahydrofuran (50 mL), followed by potassium carbonate (6.15 g, 44.2 mmol, 10.0 eq). The reaction mixture is heated under reflux for 2 hours, solvent is then evaporated, the residue is extracted with ethyl acetate (3×40 mL) and water (40 mL), and the pH is adjusted to 4 by the addition of a 0.1N hydrochloric acid aqueous solution. The combined organic layers are dried over sodium sulfate, filtered and concentrated to afford (4-nitro-pyrazol-1-yl)-acetic acid as a light yellow solid (589 mg, 78% yield).

Workup

  1. temperatureThe reaction mixture is heated
  2. temperatureunder reflux for 2 hours
  3. customsolvent is then evaporated
  4. extractionthe residue is extracted with ethyl acetate (3×40 mL) and water (40 mL)
  5. additionthe pH is adjusted to 4 by the addition of a 0.1N hydrochloric acid aqueous solution
  6. dry with materialThe combined organic layers are dried over sodium sulfate
  7. filtrationfiltered
  8. concentrationconcentrated

Sources & evidence

ORD record
ord-33f0eaf6d5d744a788d415af381d4dbd
Source dataset
uspto-grants-2015_01
Patent number
US08927541B2

Reaction notes

Loading…