Pyrazole → 1-(4-Bromo-2-ethyl-benzyl)-1H-pyrazole

HRID 859677Notes

Reaction equation

HRID 859677 reaction equation
[NH:1]1[CH:5]=[CH:4][CH:3]=[N:2]1.[Br:6][C:7]1[CH:12]=[CH:11][C:10]([CH2:13]Br)=[C:9]([CH2:15][CH3:16])[CH:8]=1>CN(C=O)C.O>[Br:6][C:7]1[CH:12]=[CH:11][C:10]([CH2:13][N:1]2[CH:5]=[CH:4][CH:3]=[N:2]2)=[C:9]([CH2:15][CH3:16])[CH:8]=1

Participants

5

Reactant 2

HCID 1048PyrazoleHCID 587640754-Bromo-1-(bromomethyl)-2-ethylbenzene

Product 1

HCID 587641661-(4-Bromo-2-ethyl-benzyl)-1H-pyrazoleYield 80%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6228DimethylformamideSolvent

Conditions

Temperature
80 °C

Procedure

A solution of pyrazole (616 mg, 9.1 mmol) in anhydrous DMF (30 mL) was treated with naH (60%, 362 mg). 4-Bromo-1-bromomethyl-2-ethyl-benzene (2.5 g, 9.1 mmol) was added and the resulting solution was stirred at 80° C. for 13 hours before it was cooled down to room temperature. The mixture was diluted with H2O, extracted with Et2O. The combined organic extracts were washed with H2O, brine, dried over MgSO4 and concentrated under reduced pressure. The residue was purified by flash column chromatography to afford the desired product (1.92 g, 80% yield). 1H NMR (300 MHz, CDCl3): δ 1.15 (t, J=7.5 Hz, 3 H), 2.59–2.66 (m, 2 H), 5.30 (s, 2 H), 6.26–6.28 (m, 1 H), 6.86–6.88 (m, 1 H), 7.29–7.32 (m, 2 H), 7.37–7.38 (m, 1 H), 7.54–7.55 (m, 1 H).

Workup

  1. temperaturewas cooled down to room temperature
  2. extractionextracted with Et2O
  3. washThe combined organic extracts were washed with H2O, brine
  4. dry with materialdried over MgSO4
  5. concentrationconcentrated under reduced pressure
  6. customThe residue was purified by flash column chromatography

Sources & evidence

ORD record
ord-ab784c76cd18492bba63f6f699ef0f40
Source dataset
uspto-grants-2006_12
Patent number
US07151105B2

Reaction notes

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