反应详情

温度

0 °C

Sodium hydride (0.7 g, 18 mmol) was added in three portions to a solution of 2-phenyl-1,3-dioxan-5-ol. (3.0 g, 17 mmol) in THF (50 mL) at −10° C. The reaction mixture was stirred at 0° C. until no gas was generated. MeI (3.5 g, 25 mmol) was then added at room temperature, and reaction mixture was stirred at room temperature for 2 h. The reaction was diluted with water (50 mL). The solvent was removed; the residue was extracted with ethyl acetate (3×50 mL). The combined organic layer was dried over sodium sulfate, filtered and concentrated under reduced pressure to give a brown crude oil which was recrystallized from THF/hexane to afford 5-methoxy-2-phenyl-1,3-dioxane as a white solid. 1H NMR (300 MHz, CDCl3) δ 7.51-7.48 (m, 2H), 7.41-7.37 (m, 3H), 5.56 (s, 1H), 4.25-4.19 (m, 2H), 4.07-4.03 (m, 2H), 3.48 (s, 3H).

1. customat −10° C
2. customreaction mixture
3. stirringwas stirred at room temperature for 2 h
4. customThe solvent was removed
5. extractionthe residue was extracted with ethyl acetate (3×50 mL)
6. dry with materialThe combined organic layer was dried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customto give a brown crude oil which
10. customwas recrystallized from THF/hexane