Dimethyl Sulfate → 4-Methoxy-1H-quinolin-2-one
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]=1Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
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).