Water → 2-Benzimidazolecarboxylic acid

HRID 2071590Notes

Reaction equation

HRID 2071590 reaction equation
[OH:1][CH2:2][C:3]1[NH:4][C:5]2[CH:11]=[CH:10][CH:9]=[CH:8][C:6]=2[N:7]=1.C(=O)([O-])[O-:13].[Na+].[Na+].O.[Mn]([O-])(=O)(=O)=O.[K+]>C(O)(=O)C>[N:7]1[C:6]2[CH:8]=[CH:9][CH:10]=[CH:11][C:5]=2[NH:4][C:3]=1[C:2]([OH:13])=[O:1]

Participants

6

Reactant 4

HCID 962WaterHCID 10340Sodium CarbonateHCID 785692-(Hydroxymethyl)-1H-benzimidazoleHCID 516875Potassium Permanganate

Product 1

HCID 2332402-Benzimidazolecarboxylic acid

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

The 2-hydroxymethylbenzimidazole from Part A (4 gms.) was refluxed in a small amount of saturated sodium carbonate solution with addition of sufficient boiling water to dissolve it. A hot, dilute solution of 6.67 gms. of potassium permanganate then was added slowly with stirring. Upon completion of the addition, the resulting suspension was refluxed for 30 minutes. The resulting hot liquid was separated by filtration from manganese dioxide which had formed. The filtrate then was cooled and rendered acidic (pH 5.0) by addition of acetic acid. The resulting yellow precipitate was filtered, dried, and recrystallized from hot water to obtain 1.98 gms. of the title compound as fine yellow needles.

Workup

  1. dissolutionto dissolve it
  2. additionUpon completion of the addition
  3. temperaturethe resulting suspension was refluxed for 30 minutes
  4. customThe resulting hot liquid was separated by filtration from manganese dioxide which
  5. customhad formed
  6. temperatureThe filtrate then was cooled
  7. filtrationThe resulting yellow precipitate was filtered
  8. customdried
  9. customrecrystallized from hot water
  10. customto obtain 1.98 gms

Sources & evidence

ORD record
ord-a332ef6d993840f79ef27933eab5ba59
Source dataset
uspto-grants-1977_09
Patent number
US04048161

Reaction notes

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