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

HRID 1686003Notes

Reaction equation

HRID 1686003 reaction equation
C([O:3][C:4](=[O:11])[CH2:5][N:6]1[CH:10]=[CH:9][CH:8]=[N:7]1)C.S(=O)(=O)(O)O.[N+:17]([O-])([OH:19])=[O:18]>>[N+:17]([C:9]1[CH:8]=[N:7][N:6]([CH2:5][C:4]([OH:3])=[O:11])[CH:10]=1)([O-:19])=[O:18]

Participants

4

Reactant 3

HCID 944Nitric AcidHCID 1118Sulfuric AcidHCID 4534671Ethyl 2-(1H-pyrazol-1-yl)acetate

Product 1

HCID 12834772-(4-nitro-1H-pyrazol-1-yl)acetic acidYield 33%

Conditions

Temperature
0 °C

Procedure

Six conical flasks were charged with pyrazol-1-yl-acetic acid ethyl ester (6×9.66 g, 6×62.6 mmol) and concentrated sulphuric acid (6×20 ml) was added. The solutions were cooled to 0° C. and concentrated nitric acid (6×10 ml) was added dropwise. The reaction mixtures were allowed to warm to room temperature and left standing for 18 hours. The combined organic mixtures were poured into ice (50 ml) and extracted with ethyl acetate (5×500 ml). The combined organic extracts were washed with brine (500 ml), dried (MgSO4), filtered and concentrated under reduced pressure to leave a yellow solid. Recrystallisation from ethyl acetate afforded the title compound as an off-white solid (20.97 g, 33% yield).

Workup

  1. additionwas added
  2. customThe reaction mixtures
  3. temperatureto warm to room temperature
  4. waitleft
  5. extractionextracted with ethyl acetate (5×500 ml)
  6. washThe combined organic extracts were washed with brine (500 ml)
  7. dry with materialdried (MgSO4)
  8. filtrationfiltered
  9. concentrationconcentrated under reduced pressure
  10. customto leave a yellow solid
  11. customRecrystallisation from ethyl acetate

Sources & evidence

ORD record
ord-c9a8134c836e4947974dd6ff72db73d4
Source dataset
uspto-grants-2012_04
Patent number
US08148531B2

Reaction notes

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