Dimethylformamide → Ethyl 7-methoxy-1-benzofuran-2-carboxylate

HRID 430784

Reaction equation

HRID 430784 reaction equation
CN(C)C=O.O=[CH:7][C:8]1[CH:16]=[CH:15][CH:14]=[C:11]([O:12][CH3:13])[C:9]=1[OH:10].Cl[CH2:18][C:19]([O:21][CH2:22][CH3:23])=[O:20].C(=O)([O-])[O-].[K+].[K+]>O>[CH3:13][O:12][C:11]1[C:9]2[O:10][C:18]([C:19]([O:21][CH2:22][CH3:23])=[O:20])=[CH:7][C:8]=2[CH:16]=[CH:15][CH:14]=1

Participants

6

Reactant 4

HCID 6228DimethylformamideHCID 7751Ethyl chloroacetateHCID 8991o-VanillinHCID 11430Potassium Carbonate

Product 1

HCID 521284Ethyl 7-methoxy-1-benzofuran-2-carboxylateYield 48%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
120 °C

Procedure

To N,N-dimethylformamide (300 ml), o-vanillin (25.2 g), ethyl chloroacetate (23.5 ml) and potassium carbonate (45 mg) were added and the resulting mixture was stirred at 120° C. for 14 hours. The reaction mixture was filtered to remove insoluble inorganic salts, and 1N hydrochloric acid (50 ml) was added to the mixture to stop the reaction. Distilled water (250 ml) was added and the resulting mixture was extracted 4 times with totally 150 ml of ethyl acetate containing 15% of n-hexane. The organic layers were washed with distilled water (100 ml) and with saturated brine (100 ml), and dried over anhydrous sodium sulfate. The sodium sulfate was removed by filtration and the solvent was concentrated to dryness under reduced pressure. The residue was purified by column chromatography (solvent: n-hexane/ethyl acetate=10/1 to 5/1) using silica gel to obtain the desired compound (17.4 g, yield: 48%) in the form of colorless needle-shaped crystals.

Workup

  1. filtrationThe reaction mixture was filtered
  2. customto remove insoluble inorganic salts, and 1N hydrochloric acid (50 ml)
  3. additionwas added to the mixture
  4. customthe reaction
  5. extractionthe resulting mixture was extracted 4 times with totally 150 ml of ethyl acetate containing 15% of n-hexane
  6. washThe organic layers were washed with distilled water (100 ml) and with saturated brine (100 ml)
  7. dry with materialdried over anhydrous sodium sulfate
  8. customThe sodium sulfate was removed by filtration
  9. concentrationthe solvent was concentrated to dryness under reduced pressure
  10. customThe residue was purified by column chromatography (solvent: n-hexane/ethyl acetate=10/1 to 5/1)

Sources & evidence

ORD record
ord-e4b60001689a4e48aa41680344af977e
Source dataset
uspto-grants-2001_11
Patent number
US06323235B1

Linked notes

Loading…