O-Phenylenediamine → 2-(5-Methylpyridin-2-yl)benzimidazole

HRID 1701300Notes

Reaction equation

HRID 1701300 reaction equation
[C:1]1([NH2:8])[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[NH2:7].[CH3:9][C:10]1[CH:11]=[CH:12][C:13]([C:16](O)=O)=[N:14][CH:15]=1.C(=O)([O-])[O-].[Na+].[Na+]>O>[CH3:9][C:10]1[CH:11]=[CH:12][C:13]([C:16]2[NH:7][C:2]3[CH:3]=[CH:4][CH:5]=[CH:6][C:1]=3[N:8]=2)=[N:14][CH:15]=1

Participants

5

Reactant 3

HCID 7243O-PhenylenediamineHCID 10340Sodium CarbonateHCID 1995755-Methylpicolinic acid

Product 1

HCID 203478002-(5-Methylpyridin-2-yl)benzimidazole

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

6.2 g. of o-phenylenediamine, 7.1 g. of 5-methylpicolinic acid and 40 g. of polyphosphoric acid were stirred under nitrogen gas current at 160° C. to 180° C. for 4 hours. To the reaction mixture were added 400 ml. of water and then a concentrated aqueous solution of sodium carbonate to neutrality. The resulting crystals were filtered off, dried and recrystallized from acetonitrile or ethyl acetate to obtain 9.4 g. of colorless needles of the product (86% of theory), M.P. 229.0°-229.5° C.

Workup

  1. additionTo the reaction mixture were added 400 ml
  2. filtrationThe resulting crystals were filtered off
  3. customdried
  4. customrecrystallized from acetonitrile or ethyl acetate
  5. customto obtain 9.4 g

Sources & evidence

ORD record
ord-4021eb0afeb6461f8c68825e1eae6d61
Source dataset
uspto-grants-1980_03
Patent number
US04192880

Reaction notes

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