Potassium Carbonate → ethyl 1-(4-ethylphenyl)-1H-imidazole-5-carboxylate

HRID 72714

Reaction equation

HRID 72714 reaction equation
[CH2:1]([C:3]1[CH:9]=[CH:8][C:6]([NH2:7])=[CH:5][CH:4]=1)[CH3:2].O=[CH:11][C:12]([O:14][CH2:15][CH3:16])=[O:13].C(=O)([O-])[O-].[K+].[K+].CC1C=CC(S([CH2:33][N+:34]#[C-:35])(=O)=O)=CC=1>C(O)C>[CH2:1]([C:3]1[CH:9]=[CH:8][C:6]([N:7]2[C:11]([C:12]([O:14][CH2:15][CH3:16])=[O:13])=[CH:35][N:34]=[CH:33]2)=[CH:5][CH:4]=1)[CH3:2]

Participants

6

Reactant 4

HCID 11430Potassium CarbonateHCID 115044-EthylanilineHCID 70211Ethyl oxoacetateHCID 161915Tosylmethyl isocyanide

Product 1

HCID 71093623ethyl 1-(4-ethylphenyl)-1H-imidazole-5-carboxylate

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

4-Ethylaniline (2.08 mL, 16.6 mmol) and ethyl oxoacetate (50% solution in toluene, 3.30 mL, 16.6 mmol) were combined in ethanol (40 mL) and stirred at room temperature for 3 hours. Potassium carbonate (5.75 g, 41.6 mmol) and isocyanomethyl 4-methylphenyl sulfone (98%, 3.98 g, 20.0 mmol) were added and the reaction mixture was heated to reflux for 3 hours. After cooling to room temperature, the reaction mixture was filtered through Celite. The filtrate was concentrated in vacuo, dissolved in ethyl acetate, washed with water, dried over magnesium sulfate, filtered, and concentrated under reduced pressure. Purification via silica gel chromatography (Gradient: 0% to 33% ethyl acetate in heptane) afforded the product as a clear brown oil that solidified upon standing. Yield: 3.03 g, 12.4 mmol, 75%. LCMS m/z 245.0 (M+1). 1H NMR (400 MHz, CDCl3) δ 1.24 (t, J=7.1 Hz, 3H), 1.29 (t, J=7.6 Hz, 3H), 2.73 (q, J=7.6 Hz, 2H), 4.21 (q, J=7.1 Hz, 2H), 7.27 (br AB quartet, JAB=8.6 Hz, ΔνAB=24 Hz, 4H), 7.66 (d, J=1.1 Hz, 1H), 7.85 (d, J=1.1 Hz, 1H).

Workup

  1. temperaturethe reaction mixture was heated
  2. temperatureto reflux for 3 hours
  3. temperatureAfter cooling to room temperature
  4. filtrationthe reaction mixture was filtered through Celite
  5. concentrationThe filtrate was concentrated in vacuo
  6. dissolutiondissolved in ethyl acetate
  7. washwashed with water
  8. dry with materialdried over magnesium sulfate
  9. filtrationfiltered
  10. concentrationconcentrated under reduced pressure
  11. customPurification via silica gel chromatography (Gradient: 0% to 33% ethyl acetate in heptane)

Sources & evidence

ORD record
ord-c2c1bc9e250c408ea7c3640a79ae49a8
Source dataset
uspto-grants-2014_09
Patent number
US08829010B2

Linked notes

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