Phosphorus oxychloride → 2-Chloro-7-(1-ethylpropyl)-1-methyl-4-(trifluoromethyl)-1H-benzimidazole

HRID 1698606Notes

Reaction equation

HRID 1698606 reaction equation
[CH2:1]([CH:3]([C:6]1[C:11]2[N:12]([CH3:16])[C:13](=O)[NH:14][C:10]=2[C:9]([C:17]([F:20])([F:19])[F:18])=[CH:8][CH:7]=1)[CH2:4][CH3:5])[CH3:2].P(Cl)(Cl)([Cl:23])=O>>[Cl:23][C:13]1[N:12]([CH3:16])[C:11]2[C:6]([CH:3]([CH2:4][CH3:5])[CH2:1][CH3:2])=[CH:7][CH:8]=[C:9]([C:17]([F:20])([F:19])[F:18])[C:10]=2[N:14]=1

Participants

3

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 672729847-(1-Ethylpropyl)-1-methyl-4-(trifluoromethyl)-1,3-dihydro-2H-benzimidazol-2-one

Product 1

HCID 672728702-Chloro-7-(1-ethylpropyl)-1-methyl-4-(trifluoromethyl)-1H-benzimidazoleYield 91%

Conditions

Temperature
110 °C

Procedure

A mixture of 7-(1-ethylpropyl)-1-methyl-4-(trifluoro-methyl)-1,3-dihydro-2H-benzimidazol-2-one (310 mg, 1.08 mmol) and phosphoryl chloride (5 ml) was heated at 110° C. for 1 h and concentrated in vacuo. Toluene was added and concentrated again to remove excess reagent. Aqueous saturated sodium bicarbonate was added to the residue and extracted with ethyl acetate. The extracts were washed with water, dried over magnesium sulfate and concentrated in vacuo. The residue was purified by column chromatography on silica gel with a 20% ethyl acetate/n-hexane to give 300 mg (0.99 mmol, 91%) of the title compound as a colorless oil.

Workup

  1. concentrationconcentrated in vacuo
  2. additionToluene was added
  3. concentrationconcentrated again
  4. customto remove excess reagent
  5. additionAqueous saturated sodium bicarbonate was added to the residue
  6. extractionextracted with ethyl acetate
  7. washThe extracts were washed with water
  8. dry with materialdried over magnesium sulfate
  9. concentrationconcentrated in vacuo
  10. customThe residue was purified by column chromatography on silica gel with a 20% ethyl acetate/n-hexane

Sources & evidence

ORD record
ord-362cf988a8ee47c09f5151899e145138
Source dataset
uspto-grants-2012_04
Patent number
US08163935B2

Reaction notes

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