Dimethyl Sulfate → 4-Methoxy-1H-quinolin-2-one

HRID 1835836Notes

Reaction equation

HRID 1835836 reaction equation
[OH:1][C:2]1[CH:11]=[C:10]([OH:12])[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[N:3]=1.[C:13](=O)([O-])[O-].[K+].[K+].S(OC)(OC)(=O)=O>CC(C)=O>[CH3:13][O:12][C:10]1[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[NH:3][C:2](=[O:1])[CH:11]=1

Participants

5

Reactant 3

HCID 6497Dimethyl SulfateHCID 11430Potassium CarbonateHCID 1785165532-hydroxy-1H-quinolin-4-one

Product 1

HCID 6001674-Methoxy-1H-quinolin-2-oneYield 54%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

To a suspension of 2,4-dihydroxy quinoline (3.00 g, 18.6 mmol) and potassium carbonate (5.14 g, 37.2 mmol) in acetone (500 mL) was added dimethyl sulfate (2.1 mL, 22 mmol) and the resulting mixture heated at reflux during 5 hrs. The solvent was removed in vacuo and the residue triturated in water. The product was collected by filtration, washed with water and triturated from methanol to give 4-methoxy 2-quinolone 187a (1.76 g, 54%) as a white solid, that had identical 1H NMR data as reported (Reisch et al., Arch. Pharm., 1980, 313, 751-755).

Workup

  1. temperaturethe resulting mixture heated
  2. temperatureat reflux during 5 hrs
  3. customThe solvent was removed in vacuo
  4. customthe residue triturated in water
  5. filtrationThe product was collected by filtration
  6. washwashed with water
  7. customtriturated from methanol

Sources & evidence

ORD record
ord-0d95bc6bdc2a4e28aa08f35d75e86a10
Source dataset
uspto-grants-2004_08
Patent number
US06774134B2

Reaction notes

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