N-bromobutanimide → 1-(4-Fluoro-3-cyanophenyl)-3-trifluoromethyl-5-bromomethylpyrazole

HRID 1768102Notes

Reaction equation

HRID 1768102 reaction equation
[F:1][C:2]1[CH:7]=[CH:6][C:5]([N:8]2[C:12]([CH3:13])=[CH:11][C:10]([C:14]([F:17])([F:16])[F:15])=[N:9]2)=[CH:4][C:3]=1[C:18]#[N:19].C1C(=O)N([Br:27])C(=O)C1.C(OOCC1C=CC=CC=1)C1C=CC=CC=1>C(Cl)(Cl)(Cl)Cl>[F:1][C:2]1[CH:7]=[CH:6][C:5]([N:8]2[C:12]([CH2:13][Br:27])=[CH:11][C:10]([C:14]([F:16])([F:15])[F:17])=[N:9]2)=[CH:4][C:3]=1[C:18]#[N:19]

Participants

5

Reactant 3

HCID 67184N-bromobutanimideHCID 11229634Benzyl PeroxideHCID 222807792-Fluoro-5-[5-methyl-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzonitrile

Product 1

HCID 222807951-(4-Fluoro-3-cyanophenyl)-3-trifluoromethyl-5-bromomethylpyrazoleYield 50.1%

Reagents, catalysts & solvents 1

HCID 5943Carbon TetrachlorideSolvent

Procedure

To a solution of 1-(4-fluoro-3-cyanophenyl)-3-trifluoromethyl-5-methylpyrazole (4.0 g, 14.9 mmol) in CCl4 (75 mL) was added NBS (5.3 g, 29.7 mmol) and benzylperoxide (0.2 g, 1.49 mmol). The reaction was brought to reflux overnight. The next day the CCl4 was evaporated and the residue was partitioned between ethyl acetate and sodium bicarbonate (sat.). The organic phase was washed with water, brine, dried over sodium sulfate, filtered and concentrated. Flash chromatography gave 1-(4-fluoro-3-cyanophenyl)-3-trifluoromethyl-5-bromomethylpyrazole (2.6 g, 50% yield) as pure compound: MS (CI): 348 (M+H)+ (100%).

Workup

  1. temperatureto reflux overnight
  2. customThe next day the CCl4 was evaporated
  3. customthe residue was partitioned between ethyl acetate and sodium bicarbonate (sat.)
  4. washThe organic phase was washed with water, brine
  5. dry with materialdried over sodium sulfate
  6. filtrationfiltered
  7. concentrationconcentrated

Sources & evidence

ORD record
ord-9eb223e0216f442a908bcba97a1c586c
Source dataset
uspto-grants-2007_06
Patent number
US07235575B2

Reaction notes

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