O-Phenylenediamine → 2-Benzimidazolepropanol

HRID 2303334

Reaction equation

HRID 2303334 reaction equation
[C:1]1([NH2:8])[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[NH2:7].[O:9]1[CH2:13][CH2:12][CH2:11][C:10]1=O>Cl>[NH:7]1[C:2]2[CH:3]=[CH:4][CH:5]=[CH:6][C:1]=2[N:8]=[C:13]1[CH2:12][CH2:11][CH2:10][OH:9]

Participants

4

Reactant 2

HCID 7243O-PhenylenediamineHCID 7302Gamma-Butyrolactone

Product 1

HCID 754702-BenzimidazolepropanolYield 95.5%

Reagents, catalysts & solvents 1

HCID 313Hydrochloric AcidSolvent

Procedure

A mixture of 5.4 g of 1,2-phenylenediamine and 4.5 g of dihydro-furan-2-one in 50 mL of 4N hydrochloric acid was heated to reflux for 20 h, 1 teaspoon of decolorizing carbon added, and after another 15 min reflux, filtered hot. The filtrate was concentrated under reduced pressure to near dryness, the residue made basic (pH=8) with saturated sodium bicarbonate and extracted into 3×80 mL of ether. The combined extracts were dried over magnesium sulfate and concentrated under reduced pressure. After drying under vacuum, 8.4 g of 3-(1H-benzimidazol-2-yl)-propan-1-ol was obtained as a solid.

Workup

  1. temperaturewas heated
  2. temperatureto reflux for 20 h
  3. addition1 teaspoon of decolorizing carbon added
  4. temperatureafter another 15 min reflux
  5. filtrationfiltered hot
  6. concentrationThe filtrate was concentrated under reduced pressure
  7. extractionextracted into 3×80 mL of ether
  8. dry with materialThe combined extracts were dried over magnesium sulfate
  9. concentrationconcentrated under reduced pressure
  10. customAfter drying under vacuum

Sources & evidence

ORD record
ord-ba3dcd2ed4b84d269380e183c5a565b2
Source dataset
uspto-grants-2002_08
Patent number
US06432976B1

Linked notes

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