反应详情

温度

-78 °C

To a cooled (−78° C.) stirring solution of 6-bromo-2,2-dimethyl-2H-chromene, which was prepared according to Chemistry and Biology, 2000, Vol. 7, p. 979, (567.7 mg, 2.38 mmol) in THF (7 mL) was added n-BuLi (2.88 M, 0.94 mL, 2.71 mmol). After completion of addition, the reaction mixture continued to stir at −78° C. After 25 minutes, (4-benzyloxy-3,5-dimethoxy-phenyl)-acetaldehyde (619.6 mg, 2.17 mmol) dissolved in THF (7.0 mL) was added. After completion of addition the reaction continued to stir for 15 minutes and was then quenched with saturated ammonium chloride. The aqueous layer was separated and extracted with ethyl acetate. All Combined organic layers were dried over sodium sulfate, filtered, and concentrated to yield a crude oil. The crude material was purified by silica gel chromatography (3:1 ethyl acetate:hexanes) to yield the desired product (200.5 mg, 20% yield).

1. customwas prepared
2. additionAfter completion of addition
3. additionwas added
4. additionAfter completion of addition the reaction
5. stirringto stir for 15 minutes
6. customwas then quenched with saturated ammonium chloride
7. customThe aqueous layer was separated
8. extractionextracted with ethyl acetate
9. dry with materialwere dried over sodium sulfate
10. filtrationfiltered
11. concentrationconcentrated
12. customto yield a crude oil
13. customThe crude material was purified by silica gel chromatography (3:1 ethyl acetate:hexanes)