O-Phenylenediamine → Benzimidazole, 2-butyl-

HRID 1886479Notes

Reaction equation

HRID 1886479 reaction equation
[C:1]1([NH2:8])[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[NH2:7]>C(O)C>[CH2:2]([C:3]1[NH:7][C:2]2[CH:3]=[CH:4][CH:5]=[CH:6][C:1]=2[N:8]=1)[CH2:1][CH2:6][CH3:5]

Participants

3

Reactant 1

HCID 7243O-Phenylenediamine

Product 1

HCID 22122Benzimidazole, 2-butyl-Yield 138%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

To a solution of o-phenylenediamine (0.171 g, 1.58 mmol) in absolute ethanol (8 ml), ethyl valerylimidate (0.313 g, 1.9 mmol) was added, and the mixture was refluxed overnight. The reaction was cooled to room temperature and concentrated in vacuo. The residue was partitioned between ethyl acetate and saturated NaHCO3. The organic phase was separated and the aqueous layer was extracted with ethyl acetate (3×20 ml). The organic layers were combined and washed with brine, dried (MgSO4), and then concentrated in vacuo. The crude product, thus obtained, was purified by medium pressure liquid chromatography (MPLC) on silica-gel using ethyl acetate-hexane (1:1) to give cream colored crystalline solid (0.19 g, 69%).

Workup

  1. temperaturethe mixture was refluxed overnight
  2. concentrationconcentrated in vacuo
  3. customThe residue was partitioned between ethyl acetate and saturated NaHCO3
  4. customThe organic phase was separated
  5. extractionthe aqueous layer was extracted with ethyl acetate (3×20 ml)
  6. washwashed with brine
  7. dry with materialdried (MgSO4)
  8. concentrationconcentrated in vacuo
  9. customThe crude product, thus obtained
  10. customwas purified by medium pressure liquid chromatography (MPLC) on silica-gel

Sources & evidence

ORD record
ord-3d6eeb33bb15409ca36f16943f8328b9
Source dataset
uspto-grants-1992_09
Patent number
US05151435

Reaction notes

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