Hydrochloric Acid → 3-Methylbenzofuran-2-carboxylic acid ethyl ester

HRID 2091009Notes

Reaction equation

HRID 2091009 reaction equation
[OH:1][C:2]1[CH:7]=[CH:6][C:5]([O:8][CH3:9])=[CH:4][C:3]=1[C:10](=O)[CH3:11].Br[CH2:14][C:15]([O:17][CH3:18])=[O:16].C(=O)([O-])[O-].[K+].[K+].C[O-].[Na+].Cl>CO.O.CN(C)C=O>[CH3:9][O:8][C:5]1[CH:6]=[CH:7][C:2]2[O:1][C:14]([C:15]([O:17][CH3:18])=[O:16])=[C:10]([CH3:11])[C:3]=2[CH:4]=1

Participants

9

Reactant 5

HCID 313Hydrochloric AcidHCID 11430Potassium CarbonateHCID 60984Methyl bromoacetateHCID 697141-(2-Hydroxy-5-methoxyphenyl)ethan-1-oneHCID 10942334Sodium Methoxide

Product 1

HCID 131570103-Methylbenzofuran-2-carboxylic acid ethyl esterYield 19%

Reagents, catalysts & solvents 3

HCID 887MethanolSolventHCID 962WaterSolventHCID 6228DimethylformamideSolvent

Procedure

To a mixture of 1-(2-hydroxy-5-methoxyphenyl)ethanone (5.00 g), methyl bromoacetate (3.13 mL) and N,N-dimethylformamide (50 mL) was added potassium carbonate (12.5 g), and the mixture was stirred overnight at room temperature. Water was added to quench the reaction, and the reaction mixture was extracted with ethyl acetate. The extract was washed with saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure to give a brown oil. To a solution (50 mL) of the obtained oil in methanol was added sodium methoxide (1.63 g), and the mixture was stirred with heating under reflux for 3 hr. 1N Hydrochloric acid was added to quench the reaction, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:4, volume ratio) to give the title object compound (1.25 g, 19%) as a white solid.

Workup

  1. customto quench
  2. customthe reaction
  3. extractionthe reaction mixture was extracted with ethyl acetate
  4. washThe extract was washed with saturated brine
  5. dry with materialdried over magnesium sulfate
  6. concentrationconcentrated under reduced pressure
  7. customto give a brown oil
  8. stirringthe mixture was stirred
  9. temperaturewith heating
  10. temperatureunder reflux for 3 hr
  11. customto quench
  12. customthe reaction
  13. extractionthe mixture was extracted with ethyl acetate
  14. washThe extract was washed with saturated brine
  15. dry with materialdried over magnesium sulfate
  16. concentrationconcentrated under reduced pressure
  17. customThe residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:4, volume ratio)

Sources & evidence

ORD record
ord-cbedb24a2a044ee6855558216ddb7020
Source dataset
uspto-grants-2013_05
Patent number
US08436043B2

Reaction notes

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