Hydrogen Bromide → Hydrogen Bromide

HRID 1729697Notes

Reaction equation

HRID 1729697 reaction equation
[NH:1]=[C:2]1[N:6]([CH2:7][CH2:8]O)[C:5]2[CH:10]=[CH:11][CH:12]=[CH:13][C:4]=2[N:3]1[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1.[BrH:20].S(Cl)(Cl)=O>C(Cl)(Cl)Cl.C(O)(C)C>[C:14]1([N:3]2[C:4]3[CH:13]=[CH:12][CH:11]=[CH:10][C:5]=3[N:6]3[CH2:7][CH2:8][N:1]=[C:2]23)[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1.[BrH:20]

Participants

7

Reactant 3

HCID 260Hydrogen Bromide2×HCID 24386Thionyl ChlorideHCID 13622676HCID 13622676, compound

Product 2

HCID 260Hydrogen BromideHCID 13077475HCID 13077475, compound

Reagents, catalysts & solvents 2

HCID 3776IsopropanolSolventHCID 6212ChloroformSolvent

Procedure

A solution of 2,3-dihydro-2-imino-3-phenyl-1H-benzimidazole-1-ethanol [prepared by basification of the hydrobromide (2.23 g.)]and thionyl chloride (1.5 ml.) in chloroform (20 ml.) was heated under reflux for 2 hours. After removal of the solvent the oily residue was dissolved in ethanol (50 ml.), 10N aqueous sodium hydroxide solution (2ml.) added and the solution heated under reflux for 5 hours. After removal of the ethanol the residue was taken up in chloroform, washed twice with water and dried over magnesium sulphate. Removal of the chloroform gave an oil which was taken up in isopropanol and acidified with conc. hydrobromic acid. The isopropanol was evaporated and the residue crystallised from acetone. The product (0.862 g., m.p. 223°-225°C.) was recrystallised from ethanol/ether to give the title compound as its hydrobromide (0.765 g., m.p. 225°-228° C).

Workup

  1. temperatureunder reflux for 2 hours
  2. customAfter removal of the solvent the oily residue
  3. dissolutionwas dissolved in ethanol (50 ml.)
  4. addition10N aqueous sodium hydroxide solution (2ml.) added
  5. temperaturethe solution heated
  6. temperatureunder reflux for 5 hours
  7. customAfter removal of the ethanol the residue
  8. washwashed twice with water
  9. dry with materialdried over magnesium sulphate
  10. customRemoval of the chloroform
  11. customgave an oil which
  12. customThe isopropanol was evaporated
  13. customthe residue crystallised from acetone
  14. customThe product (0.862 g., m.p. 223°-225°C.) was recrystallised from ethanol/ether

Sources & evidence

ORD record
ord-56a47c43dc5641e9bc7c92802e3fefba
Source dataset
uspto-grants-1976_11
Patent number
US03989709

Reaction notes

Loading…