Imidazole → Ethyl 1H-imidazole-1-butanoate

HRID 1723066Notes

Reaction equation

HRID 1723066 reaction equation
[NH:1]1[CH:5]=[CH:4][N:3]=[CH:2]1.[H-].[Na+].Br[CH2:9][CH2:10][CH2:11][C:12]([O:14][CH2:15][CH3:16])=[O:13]>C1C=CC=CC=1>[N:1]1([CH2:9][CH2:10][CH2:11][C:12]([O:14][CH2:15][CH3:16])=[O:13])[CH:5]=[CH:4][N:3]=[CH:2]1

Participants

5

Reactant 3

HCID 795ImidazoleHCID 24758Sodium hydrideHCID 76300Ethyl 4-bromobutyrate

Product 1

HCID 3055389Ethyl 1H-imidazole-1-butanoateYield 30.2%

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent2×

Procedure

Part A. A solution of imidazole (17.0 g, 0.25 mole) in benzene (200 mL) at room temperature was treated with sodium hydride (60% w/w oil dispersion; 8.0 g, 0.20 mole) and heated at reflux for 1 hour. After cooling to room temperature, a solution of ethyl 4-bromobutyrate (30.0 g, 0.20 mole) in benzene (50 mL) was added. The resulting mixture was again heated at reflux for 20 hours. After cooling to room temperature, the solution was washed with water, dried (MgSO4) and concentrated under reduced pressure. The residual yellow oil was subjected to kugelrohr distillation at 125°-135° under rotary vacuum pump pressure to provide ethyl 4-(1-imidazolyl)butyrate as a colorless liquid (11.0 g, 30% yield). NMR(CDCl3) 7.44(1H,s) 7.04(1H,s) 6.90(1H,s) 4.12(2H,q,J=7 Hz) 4.02(2H,t,J=8 Hz) 2.24(2H,t,J=8 Hz) 2.08(2H,m) 1.31(3H,t,J=7 Hz).

Workup

  1. temperatureheated
  2. temperatureat reflux for 1 hour
  3. temperatureThe resulting mixture was again heated
  4. temperatureat reflux for 20 hours
  5. temperatureAfter cooling to room temperature
  6. washthe solution was washed with water
  7. dry with materialdried (MgSO4)
  8. concentrationconcentrated under reduced pressure
  9. distillationdistillation at 125°-135° under rotary vacuum pump pressure

Sources & evidence

ORD record
ord-ac635116a30d480ca3f5e1371fe4708c
Source dataset
uspto-grants-1989_08
Patent number
US04859693

Reaction notes

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