Dimethyl Sulfate → 8-Methoxyquinoline-5-carbaldehyde

Reaktionsgleichung

[OH:1][C:2]1[C:11]2[N:10]=[CH:9][CH:8]=[CH:7][C:6]=2[C:5]([CH:12]=[O:13])=[CH:4][CH:3]=1.C[O-].[Na+].S(OC)(O[CH3:21])(=O)=O>CS(C)=O>[CH3:21][O:1][C:2]1[C:11]2[N:10]=[CH:9][CH:8]=[CH:7][C:6]=2[C:5]([CH:12]=[O:13])=[CH:4][CH:3]=1

Komponenten

Versuchsvorschrift

To a solution of 0.76 g (4.39 mmol) of 8-hydroxyquinoline-5-carboxaldehyde (G. R. Clemo and R. Howe, J. Chem. Soc., 1955, 3522) in 5 mL of dimethyl sulfoxide was added 0.24 g (4.4 mmol) of sodium methoxide, while keeping the mixture under nitrogen. After stirring for 5 min, 0.56 g (4.4 mmol) of dimethyl sulfate was added. The reaction was stirred for 1 hr and the solvent removed under vacuum. The residue was partitioned between dichloromethane (100 mL) and 0.5N sodium hydroxide (50 mL); the organic layer was washed with water (100 mL), dried over anhydrous magnesium sulfate, and concentrated to give 0.61 g (74%) of 8-methoxyquinoline-5-carboxaldehyde, mp 121°-122° after recrystallization from ethanol-hexane (2:25). Anal. Calcd for C11H9NO2 : C, 70.58; H, 4.85; N, 7.48. Found: C, 70.55; H, 4.91; N, 7.44.