Water → 2-Propyl-1H-benzimidazole

HRID 653695Notes

Reaction equation

HRID 653695 reaction equation
[C:1]1([NH2:8])[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[NH2:7].O>C(OC(=O)CCC)(=O)CCC>[CH2:1]([C:6]1[NH:7][C:2]2[CH:3]=[CH:4][CH:5]=[CH:6][C:1]=2[N:8]=1)[CH2:2][CH3:3]

Participants

4

Conditions

Temperature
110 °C

Procedure

A mixture of o-phenylenediamine (2.2 g) in butyric anhydride (4.7 g) was stirred for 4 hours at 110° C. To the reaction mixture was added water, which was extracted with ethyl acetate. The organic layer was washed with an aqueous solution of sodium bicarbonate, dilute hydrochloric acid and water and then dried. The solvent was evaporated to dryness, and the residue was refluxed for 1.5 hour in 3N-HCl (35 ml). The reaction mixture was made basic with a 6N NaOH. The crystals were recrystallized from ethyl acetate-hexane to give colorless plates (0.9 g, 38%), m.p. 160°-162° C.

Workup

  1. extractionwas extracted with ethyl acetate
  2. washThe organic layer was washed with an aqueous solution of sodium bicarbonate, dilute hydrochloric acid and water
  3. customdried
  4. customThe solvent was evaporated to dryness
  5. temperaturethe residue was refluxed for 1.5 hour in 3N-HCl (35 ml)
  6. customThe crystals were recrystallized from ethyl acetate-hexane
  7. customto give colorless plates (0.9 g, 38%), m.p. 160°-162° C.

Sources & evidence

ORD record
ord-40e03bebeaf8413a9cafd5296a269521
Source dataset
uspto-grants-1992_07
Patent number
US05128356

Reaction notes

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