Acetic Anhydride → (4-((5,5-Dimethyl-1,3-dioxan-2-yl)methoxy)-3-methylpyridin-2-yl)methanol
Reaktionsgleichung
[CH3:1][C:2]1([CH3:19])[CH2:7][O:6][CH:5]([CH2:8][O:9][C:10]2[CH:15]=[CH:14][N+:13]([O-])=[C:12]([CH3:17])[C:11]=2[CH3:18])[O:4][CH2:3]1.C(OC(=O)C)(=[O:22])C.[OH-].[Na+]>>[CH3:1][C:2]1([CH3:19])[CH2:7][O:6][CH:5]([CH2:8][O:9][C:10]2[CH:15]=[CH:14][N:13]=[C:12]([CH2:17][OH:22])[C:11]=2[CH3:18])[O:4][CH2:3]1Komponenten
4
Reaktionsbedingungen
- Temperatur
- 85 °C
Versuchsvorschrift
The 4-((5,5-dimethyl-1,3-dioxan-2-yl)methoxy)-2,3-dimethylpyridine 1-oxide (3.1 g, 11.6 mmol) obtained by the step (1c) was mixed with acetic anhydride (9.87 ml, 104 mmol). After the mixture was stirred at 85° C. for 45 minutes, acetic anhydride was removed. The residue was dissolved in methanol (40 ml) and a 5N aqueous sodium hydroxide solution (5.1 ml, 25.5 mmol) was added to the mixture while cooling on ice. The mixture was stirred at room temperature for one hour. Methanol was distilled off and ice water was added to the residue, which was then extracted with ethyl acetate. The organic layer was washed with a saturated saline solution, dried over anhydrous magnesium sulfate. After the solvent was distilled off, the resultant mixture was purified by silica gel column chromatography (silica gel: 120 g, elution solvent: ethyl acetate/heptane=1/4 to 4/1) to obtain the title compound (1.23 g, yield: 39.7%) as a light yellow oil.