Phosgene → Benzimidazol-2-one

HRID 359898Notes

Reaction equation

HRID 359898 reaction equation
[C:1](Cl)(Cl)=[O:2].[C:5]1([NH2:12])[CH:10]=[CH:9][CH:8]=[CH:7][C:6]=1[NH2:11].[OH-].[Na+]>O>[N:11]1[C:1](=[O:2])[N:12]=[C:5]2[CH:10]=[CH:9][CH:8]=[CH:7][C:6]=12

Participants

5

Reactant 3

HCID 6371PhosgeneHCID 7243O-PhenylenediamineHCID 14798Sodium Hydroxide

Product 1

HCID 162542Benzimidazol-2-oneYield 98%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

100 g (1.01 mol) of phosgene are passed into 108 g (1 mol) of o-phenylenediamine in 450 ml of water at 80° C. over a period of 4 hours, and the pH is kept constant at 10 by simultaneous metering in of 407 g (2.04 mol) of 20% strength aqueous sodium hydroxide solution. The end point of the reaction is determined by sampling for diazotizable amine. After cooling, the product which has precipitated is filtered off with suction, washed with water and dried. 131 g of benzimidazolone of melting point 308° C., which corresponds to a yield of 98% of theory, are obtained in this manner.

Workup

  1. temperatureAfter cooling
  2. customthe product which has precipitated
  3. filtrationis filtered off with suction
  4. washwashed with water
  5. customdried
  6. customare obtained in this manner

Sources & evidence

ORD record
ord-787ee97f12bc4babb5d5c577a6add981
Source dataset
uspto-grants-1991_03
Patent number
US05003079

Reaction notes

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