Hydrochloric Acid → 5-chloro-1,3-dihydro-1-(3-hydroxypropyl)-2H-benzimidazol-2-one

HRID 971738

Reaction equation

HRID 971738 reaction equation
[NH2:1][C:2]1[CH:7]=[C:6]([Cl:8])[CH:5]=[CH:4][C:3]=1[NH:9][CH2:10][CH2:11][CH2:12][OH:13].Cl.[N-]=[C:16]=[O:17].[K+]>O>[Cl:8][C:6]1[CH:5]=[CH:4][C:3]2[N:9]([CH2:10][CH2:11][CH2:12][OH:13])[C:16](=[O:17])[NH:1][C:2]=2[CH:7]=1

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 30173573-((2-Amino-4-chlorophenyl)amino)propan-1-olHCID 11051572Potassio isocyanate

Product 1

HCID 30173585-chloro-1,3-dihydro-1-(3-hydroxypropyl)-2H-benzimidazol-2-oneYield 32%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Procedure

To a stirred solution of 40 parts of 3-[(2-amino-4-chlorophenyl)amino]-1-propanol in 140 parts of water and 24 parts of a hydrochloric acid solution 10 N is added dropwise a solution of 18 parts of potassium isocyanate in 40 parts of water (exothermic reaction: temperature rises to 35° C.). Upon completion, stirring is continued first for 30 minutes at room temperature and further for 20 hours at reflux temperature. The reaction mixture is allowed to stirr over week-end without heating. The precipitated product is filtered off and treated with a diluted hydrochloric acid solution in 4-methyl-2-pentanone. The whole is stirred and the layers are separated. The 4-methyl-2-pentanone-phase is washed with water, dried, filtered and evaporated, yielding 18 parts (32%) of 5-chloro-1,3-dihydro-1-(3-hydroxypropyl)-2H-benzimidazol-2-one; mp. 148.8° C.

Workup

  1. temperatureat reflux temperature
  2. waitto stirr over week-end
  3. temperaturewithout heating
  4. filtrationThe precipitated product is filtered off
  5. additiontreated with a diluted hydrochloric acid solution in 4-methyl-2-pentanone
  6. stirringThe whole is stirred
  7. customthe layers are separated
  8. washThe 4-methyl-2-pentanone-phase is washed with water
  9. customdried
  10. filtrationfiltered
  11. customevaporated

Sources & evidence

ORD record
ord-274b27e91a3f4b12a4d350dbab8b238d
Source dataset
uspto-grants-1979_07
Patent number
US04160836

Linked notes

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