2,2-Diethoxyethylamine → 2-(1H-IMIDAZOL-2-YL)-BENZONITRILE HCL

HRID 857700Notes

Reaction equation

HRID 857700 reaction equation
[ClH:1].C(O[C:5](=[NH:14])[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][C:7]=1[C:12]#[N:13])C.C(O[CH:18](OCC)[CH2:19][NH2:20])C>CO>[ClH:1].[NH:20]1[CH:19]=[CH:18][N:14]=[C:5]1[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][C:7]=1[C:12]#[N:13]

Participants

4

Reactant 2

HCID 695242,2-DiethoxyethylamineHCID 69589883HCID 69589883, compound

Product 1

HCID 218661592-(1H-IMIDAZOL-2-YL)-BENZONITRILE HCLYield 3.6%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A solution of 2-cyano-benzimidic acid ethyl ester hydrochloride (43 g, 0.20 mol) and 2,2-diethoxy-ethylamine (30 ml, 0.21 mol) in methanol (430 ml) was aged at room temperature for 1 h. The reaction mixture was concentrated to remove methanol and conc. sulfuric acid (110 ml) was added. After heating on a steam bath for 1.5 h, the reaction mixture was diluted with water (700 ml) and extracted with chloroform. The aqueous phase was made strongly basic with sodium hydroxide and extracted with chloroform. Hydrochloric acid (12N) was added to give pH 3-4, tar was filtered and the filtrate was concentrated. The resultant brown solid was sublimed at 200–220° C. The purified solid was dissolved in hydrochloric acid solution (6N, 110 ml), byproducts filtered and the filtrate concentrated. The residue was diluted with ethanol (100–120 ml) containing hydrochloric acid (12N, 1 ml), boiled briefly and filtered. Further concentration and cooling of the filtrate gave 2-(1H-imidazol-2-yl-benzonitrile hydrochloride (1.5 g). The filtrate was concentrated further and diluted with acetone. Filtration gave 2-(1H-imidazol-2-yl)-benzoic acid hydrochloride (7.3 g). Dilution of the filtrate with acetone and filtration of the resultant solid gave additional 2-(1H-imidazol-2-yl)-benzonitrile hydrochloride; mp 200–204° C.; IR 4.5μ.

Workup

  1. concentrationThe reaction mixture was concentrated
  2. customto remove methanol and conc. sulfuric acid (110 ml)
  3. additionwas added
  4. temperatureAfter heating on a steam bath for 1.5 h
  5. additionthe reaction mixture was diluted with water (700 ml)
  6. extractionextracted with chloroform
  7. extractionextracted with chloroform
  8. additionHydrochloric acid (12N) was added
  9. customto give pH 3-4, tar
  10. filtrationwas filtered
  11. concentrationthe filtrate was concentrated
  12. customwas sublimed at 200–220° C
  13. dissolutionThe purified solid was dissolved in hydrochloric acid solution (6N, 110 ml)
  14. filtrationbyproducts filtered
  15. concentrationthe filtrate concentrated
  16. additionThe residue was diluted with ethanol (100–120 ml)
  17. additioncontaining hydrochloric acid (12N, 1 ml)
  18. filtrationfiltered
  19. concentrationFurther concentration
  20. temperaturecooling of the filtrate

Sources & evidence

ORD record
ord-509d67ac0e824c2daecbfb1e3a3ac40f
Source dataset
uspto-grants-2006_12
Patent number
US07144899B2

Reaction notes

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