O-Phenylenediamine → 2-Methylbenzimidazole

HRID 375626Notes

Reaction equation

HRID 375626 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1[NH2:8].[NH4+].[OH-].[C:11](OC(=O)C)(=O)[CH3:12]>>[CH3:11][C:12]1[NH:1][C:2]2[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=2[N:8]=1

Participants

4

Reactant 3

HCID 7243O-PhenylenediamineHCID 7918Acetic AnhydrideHCID 14923Ammonium Hydroxide

Product 1

HCID 119842-Methylbenzimidazole

Procedure

A solution of 1,2-diaminobenzene (5.00 g, 46.3 mmol) in acetic anhydride (36.5 mL) was heated for 17 hours at 90° C. and then stirred for 17 hours at ambient temperature. The reaction mixture was taken to pH 9 by dropwise addition of NH4OH, with ice added as necessary to keep the mixture cool, followed by cooling in an ice bath. The resulting precipitate was filtered, rinsed with H2O, and dried in a vacuum oven to give 5.28 g of 2-methylbenzimidazole as a brown solid.

Workup

  1. additionadded as necessary
  2. temperaturecool
  3. temperatureby cooling in an ice bath
  4. filtrationThe resulting precipitate was filtered
  5. washrinsed with H2O
  6. customdried in a vacuum oven

Sources & evidence

ORD record
ord-2cd496d6c9174552a6eabfe12465b3e9
Source dataset
uspto-grants-1996_01
Patent number
US05486525

Reaction notes

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