反应详情

温度

10 °C

A solution of methylmagnesium bromide (3.0 M in THF, 1.67 mL, 5.0 mmol) was added slowly into a solution of 6-bromo-7-methoxy-2,2-dimethyl-chroman-4-one (Compound 4, 710 mg, 2.5 mmol) in 10 mL of THF at −30° C. The mixture was stirred and warmed to 10° C. for 2 h. The reaction mixture was quenched with 10% HCl and extracted with ethyl acetate. The combined organic layers were washed with a saturated solution of NH4Cl, dried (MgSO4) and concentrated at reduced pressure to give a crude oil, which was then dissolved in 10 mL of dichloromethane and cooled to 0° C. with an ice bath. To this solution was added p-toluenesulfonic acid (100 mg). After stirring for 3 h at 0° C., the reaction mixture was quenched with water, extracted with dichloromethane, washed with brine, dried (MgSO4) and concentrated at reduced pressure to give a colorless oil. Purification by flash chromatography (silica gel, 95.5 hexane/ethyl acetate) gave the title compound as a colorless oil.

1. customThe reaction mixture was quenched with 10% HCl
2. extractionextracted with ethyl acetate
3. washThe combined organic layers were washed with a saturated solution of NH4Cl
4. dry with materialdried (MgSO4)
5. concentrationconcentrated at reduced pressure
6. customto give a crude oil, which
7. temperaturecooled to 0° C. with an ice bath
8. stirringAfter stirring for 3 h at 0° C.
9. customthe reaction mixture was quenched with water
10. extractionextracted with dichloromethane
11. washwashed with brine
12. dry with materialdried (MgSO4)
13. concentrationconcentrated at reduced pressure
14. customto give a colorless oil
15. customPurification by flash chromatography (silica gel, 95.5 hexane/ethyl acetate)