Benzoyl Peroxide → 1-(4-Fluoro-3-cyanophenyl)-3-trifluoromethyl-5-bromomethylpyrazole

HRID 1266314Notes

Reaction equation

HRID 1266314 reaction equation
[C:1]([C:3]1[CH:4]=[C:5]([N:10]2[C:14]([CH3:15])=[CH:13][C:12]([C:16]([F:19])([F:18])[F:17])=[N:11]2)[CH:6]=[CH:7][C:8]=1[F:9])#[N:2].C1C(=O)N([Br:27])C(=O)C1.C(OOC(=O)C1C=CC=CC=1)(=O)C1C=CC=CC=1>C(Cl)(Cl)(Cl)Cl>[C:1]([C:3]1[CH:4]=[C:5]([N:10]2[C:14]([CH2:15][Br:27])=[CH:13][C:12]([C:16]([F:18])([F:19])[F:17])=[N:11]2)[CH:6]=[CH:7][C:8]=1[F:9])#[N:2]

Participants

5

Reactant 3

HCID 7187Benzoyl PeroxideHCID 67184N-bromobutanimideHCID 222807792-Fluoro-5-[5-methyl-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzonitrile

Product 1

HCID 222807951-(4-Fluoro-3-cyanophenyl)-3-trifluoromethyl-5-bromomethylpyrazoleYield 48.3%

Reagents, catalysts & solvents 1

HCID 5943Carbon TetrachlorideSolvent

Procedure

To a solution of 1-(3-cyano-4-fluorophenyl)-3-trifluoromethyl-5-methyl pyrazole(4.0 g, 14.87 mmol) in carbon tetrachloride(50 mL) was added NBS (2.65 g, 14.87 mmol) and benzoyl peroxide (0.36 g, 1.48 mmol). The reaction mixture was brought to reflux overnight. Solvent was removed on rotary evaporator under reduced pressure. Residue was partitioned between ethyl acetate (80 mL) and sodium bicarbonate (sat. 80 mL). Organic phase was separated and washed with water (60 mL); dried over sodium sulfate; filtered, concentrated and subjected to silica-gel flash chromatography (ethyl acetate:hexane, 1:10) to afford 1-(3-cyano-4-fluorophenyl)-3-trifluoromethyl-5-bromomethyl pyrazole (2.5 g). CI mass spectrum m/z (rel. intensity) 348 (M+H, 100).

Workup

  1. temperatureto reflux overnight
  2. customSolvent was removed on rotary evaporator under reduced pressure
  3. customResidue was partitioned between ethyl acetate (80 mL) and sodium bicarbonate (sat. 80 mL)
  4. customOrganic phase was separated
  5. washwashed with water (60 mL)
  6. dry with materialdried over sodium sulfate
  7. filtrationfiltered
  8. concentrationconcentrated

Sources & evidence

ORD record
ord-63b8fbea6459448aa84b262df2098ad5
Source dataset
uspto-grants-2003_04
Patent number
US06548512B1

Reaction notes

Loading…