m-Chloroperbenzoic acid → 2-Ethyl-5-hydroxy-2,3-dihydro-benzofuran-2-carboxylic acid methyl ester

HRID 2113158Notes

Reaction equation

HRID 2113158 reaction equation
C([C:4]1[CH:5]=[CH:6][C:7]2[O:11][C@:10]([CH2:16][CH3:17])([C:12]([O:14][CH3:15])=[O:13])[CH2:9][C:8]=2[CH:18]=1)(=O)C.ClC1C=CC=C(C(OO)=[O:27])C=1.C([O-])(O)=O.[Na+]>ClCCl>[CH3:15][O:14][C:12]([C:10]1([CH2:16][CH3:17])[CH2:9][C:8]2[CH:18]=[C:4]([OH:27])[CH:5]=[CH:6][C:7]=2[O:11]1)=[O:13]

Participants

5

Reactant 3

HCID 70297m-Chloroperbenzoic acidHCID 516892Sodium BicarbonateHCID 57978455methyl (2S)-5-acetyl-2-ethyl-2,3-dihydro-benzofuran-2-carboxylate

Product 1

HCID 111603732-Ethyl-5-hydroxy-2,3-dihydro-benzofuran-2-carboxylic acid methyl ester

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

Methyl (2S)-5-acetyl-2-ethyl-2,3-dihydro-benzofuran-2-carboxylate (3.8 g, ca. 15 mmol), m-chloroperbenzoic acid (70%, 7.7 g, 30 mmol) and NaHCO3 (3.8 g, 45 mmol) in dichloromethane (150 mL) was stirred under reflux for 2 hrs. The reaction mixture was washed successively with saturated aqueous sodium sulfite (100 mL) and aqueous NaHCO3 (2×100 mL). After removal of solvent, the residue was dissolved in methanol (100 mL) and treated with aqueous KOH (5 N, 3 mL) at 0° C. for 5 min. The reaction was neutralized with excess solid sodium bicarbonate, filtered and concentrated. The residue was purified by chromatography on silica gel eluting with 8:2 hexane:ethyl acetate to give the title compound.

Workup

  1. temperatureunder reflux for 2 hrs
  2. washThe reaction mixture was washed successively with saturated aqueous sodium sulfite (100 mL) and aqueous NaHCO3 (2×100 mL)
  3. customAfter removal of solvent
  4. dissolutionthe residue was dissolved in methanol (100 mL)
  5. additiontreated with aqueous KOH (5 N, 3 mL) at 0° C. for 5 min
  6. filtrationfiltered
  7. concentrationconcentrated
  8. customThe residue was purified by chromatography on silica gel eluting with 8:2 hexane

Sources & evidence

ORD record
ord-d5cbd9af20644f28ad44e77286bc979e
Source dataset
uspto-grants-2009_04
Patent number
US07524882B2

Reaction notes

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