Sulfuric Acid → HCID 20463284, compound

HRID 325943Notes

Reaction equation

HRID 325943 reaction equation
[Mg].Br[C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][C:4]=1[CH3:9].C[O:11][C:12]([C:14]1[N:15]=[CH:16][NH:17][C:18]=1[CH3:19])=O.S(=O)(=O)(O)O>O1CCCC1.O>[CH3:19][C:18]1[NH:17][CH:16]=[N:15][C:14]=1[C:12](=[O:11])[C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][C:4]=1[CH3:9]

Participants

7

Reactant 4

HCID 1118Sulfuric AcidHCID 72362-BromotolueneHCID 587740Methyl 5-methyl-1H-imidazole-4-carboxylateHCID 5462224Magnesium2×

Product 1

HCID 20463284HCID 20463284, compound

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
50 °C

Procedure

4.9 g of dry magnesium turnings are covered with 50 ml of dry tetrahydrofuran. The mixture is heated to boiling and a solution of 34 g of 2-bromotoluene in 50 ml of dry tetrahydrofuran is added dropwise at such a rate that a smooth reaction is maintained. After the addition is complete, the reaction mixture is refluxed for about 30 minutes until the magnesium turnings no longer react. The reaction mixture is then cooled to about 50° C. and 20 g of 5-methyl-4-imidazole-carboxylic acid methyl ester are added in small portions. After the addition is complete, the mixture is refluxed for another 2 hours and the solvent is then distilled off to give about half of the original volume. The mixture is cooled and poured into 300 ml of cold water containing 15 ml of concentrated sulfuric acid, with agitation. The stirring is continued for an additional 15 minutes and the mixture is then filtered. The pH of the filtrate is adjusted to 7-11 and the solution is extracted three times with 30 ml portions of chloroform. The combined chloroform extracts are washed with water and evaporated to dryness. The residue, which contains the crude product, is converted to the hydrochloride in ethanol. After recrystallization from ethanol, the hydrochloride melts at 289°-291° C. The 5-methyl-4-(2'-methylbenzoyl)-1H-imidazole is liberated from the hydrochloride in water with sodium hydroxide. It melts at 165°-166° C.

Workup

  1. temperatureThe mixture is heated
  2. customthat a smooth reaction
  3. temperatureis maintained
  4. additionAfter the addition
  5. customno longer react
  6. additionAfter the addition
  7. temperaturethe mixture is refluxed for another 2 hours
  8. distillationthe solvent is then distilled off
  9. customto give about half of the original volume
  10. temperatureThe mixture is cooled
  11. filtrationthe mixture is then filtered
  12. extractionthe solution is extracted three times with 30 ml portions of chloroform
  13. washThe combined chloroform extracts are washed with water
  14. customevaporated to dryness
  15. customAfter recrystallization from ethanol

Sources & evidence

ORD record
ord-21e110feac5c40eda70c690456ffdbd0
Source dataset
uspto-grants-1984_04
Patent number
US04443466

Reaction notes

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