2,5-Dimethoxytetrahydrofuran → HCID 14962900, compound

HRID 248616Notes

Reaction equation

HRID 248616 reaction equation
[NH2:1][C:2]1[N:3]=[C:4]([CH2:11][CH2:12][CH3:13])[NH:5][C:6]=1[C:7]([O:9][CH3:10])=[O:8].C([O-])(=O)C.[Na+].CO[CH:21]1[CH2:25][CH2:24][CH:23](OC)O1>C(O)(=O)C>[CH2:11]([C:4]1[NH:5][C:6]([C:7]([O:9][CH3:10])=[O:8])=[C:2]([N:1]2[CH:21]=[CH:25][CH:24]=[CH:23]2)[N:3]=1)[CH2:12][CH3:13]

Participants

5

Reactant 3

HCID 790982,5-DimethoxytetrahydrofuranHCID 517045Sodium AcetateHCID 19106906HCID 19106906, compound

Product 1

HCID 14962900HCID 14962900, compoundYield 46.2%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

To stirred acetic acid (1.5 L) at 80° C. was added over a 5-minute period a mixture of methyl 4-amino-2-propylimidazol-5-carboxylate (Example 4, 145 g, 0.798 mol) and sodium acetate (388 g, 4.73 mol). The mixture was heated at reflux for 5 minutes and then 2,5-dimethoxy-tetrahydrofuran (117 g, 0.885 mol) added all at once. The resulting dark solution was refluxed for 20 minutes, then poured onto ice. The gummy mixture was extracted with dichloromethane, the combined organic layers washed with water and dried over anhydrous magnesium sulfate. The filtrate was concentrated under reduced pressure and the residue dissolved in dichloromethane (2 L). The dichloromethane solution was treated with silica gel (500 g) and the suspension filtered through a bed of silica gel (300 g) eluting with dichloromethane. The filtrate was evaporated to dryness under reduced pressure and the crude product recrystallized from ether/hexane (2:1) to provide 86 g (46% yield) methyl 2-propyl-4-(1H-pyrrol-1-yl)imidazol-5-carboxylate, mp 135°-138° C. MS (DEI) 234 (M+1).

Workup

  1. additionwas added over a 5-minute period
  2. temperatureThe mixture was heated
  3. temperatureat reflux for 5 minutes
  4. temperatureThe resulting dark solution was refluxed for 20 minutes
  5. additionpoured onto ice
  6. extractionThe gummy mixture was extracted with dichloromethane
  7. washthe combined organic layers washed with water
  8. dry with materialdried over anhydrous magnesium sulfate
  9. concentrationThe filtrate was concentrated under reduced pressure
  10. dissolutionthe residue dissolved in dichloromethane (2 L)
  11. additionThe dichloromethane solution was treated with silica gel (500 g)
  12. filtrationthe suspension filtered through a bed of silica gel (300 g)
  13. washeluting with dichloromethane
  14. customThe filtrate was evaporated to dryness under reduced pressure
  15. customthe crude product recrystallized from ether/hexane (2:1)

Sources & evidence

ORD record
ord-d0ba1f1831a44eada6360088da4bd019
Source dataset
uspto-grants-1993_05
Patent number
US05210211

Reaction notes

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