Methanol → 3-(3-Amino-pyrazol-1-ylmethyl)-benzoic acid methyl ester

HRID 546089Notes

Reaction equation

HRID 546089 reaction equation
[CH3:1][O:2][C:3](=[O:19])[C:4]1[CH:9]=[CH:8][CH:7]=[C:6]([CH2:10][N:11]2[CH:15]=[CH:14][C:13]([N+:16]([O-])=O)=[N:12]2)[CH:5]=1.CO.NN>C(OCC)(=O)C.[Ni].O>[CH3:1][O:2][C:3](=[O:19])[C:4]1[CH:9]=[CH:8][CH:7]=[C:6]([CH2:10][N:11]2[CH:15]=[CH:14][C:13]([NH2:16])=[N:12]2)[CH:5]=1

Participants

7

Reactant 3

HCID 887MethanolHCID 9321HydrazineHCID 67191930HCID 67191930, compound

Product 1

HCID 671899153-(3-Amino-pyrazol-1-ylmethyl)-benzoic acid methyl esterYield 69.1%

Reagents, catalysts & solvents 3

HCID 935NickelCatalystHCID 962WaterSolventHCID 8857Ethyl AcetateSolvent2×

Procedure

The 3-(3-nitro-pyrazol-1-ylmethyl)-benzoic acid methyl ester (1.78 g, 6.82 mmol) was dissolved in ethyl acetate (5 mL) and methanol (5 mL) was added. While stirring, a 50% slurry of raney nickel in water (1 mL) was added followed by hydrazine (1.5 mL). Immediate effervescence was observed. The reaction continued to stir and bubble for 30 min. The reaction was passed through a plug of celite and concentrated in vacuo to give a yellow oil. The oil was taken up in ethyl acetate (100 mL), washed with water (2×20 mL), saturated aqueous brine solution (20 mL), dried over magnesium sulfate and concentrated in vacuo. Purification by ISCO flash column chromatography (Teledyne Isco RediSep Flash Column 120 g; 15% ethyl acetate/hexanes to 100% ethyl acetate/hexanes) afforded 3-(3-amino-pyrazol-1-ylmethyl)-benzoic acid methyl ester (1.09 g, 69%) as a beige solid: H1-NMR (400 MHz, DMSO-d6) δ 3.83 (3H, s), 4.57 (2H, bs), 5.09 (2H, s), 5.41 (1H, d, J=2.0 Hz), 7.44-7.46 (3H, m), 7.76 (1H, bs), 7.82-7.84 (1H, m).

Workup

  1. stirringto stir
  2. custombubble for 30 min
  3. concentrationconcentrated in vacuo
  4. customto give a yellow oil
  5. washwashed with water (2×20 mL), saturated aqueous brine solution (20 mL)
  6. dry with materialdried over magnesium sulfate
  7. concentrationconcentrated in vacuo
  8. customPurification by ISCO flash column chromatography (Teledyne Isco RediSep Flash Column 120 g; 15% ethyl acetate/hexanes to 100% ethyl acetate/hexanes)

Sources & evidence

ORD record
ord-eecad71be342413e8c30bafea1b1c79c
Source dataset
uspto-grants-2011_05
Patent number
US07935699B2

Reaction notes

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