反应详情

温度

63 °C

To a suspension of Mg turnings (1.1 g, 0.05 g-at.) and catalytic amount of iodine in 200 mL THF was added dropwise 2-(2-bromoethyl)-[1,3]dioxolane (4.3 g, 0.02 mol) with heating over a period of 30 min. The resulting mixture was stirred for 30 min at 63° C. and then cooled to −30° C. and 4-fluoro-3-methyl-benzaldehyde (3.0 g, 0.02 mol) added slowly as a solution in 50 mL of THF. The temperature was maintained at −30° C. for 1 h and then slowly raised to room temperature over a period of 3 h. The excess Grignard was destroyed by the careful addition of 200 mL saturated aqueous NH4Cl. The mixture was extracted with ethyl acetate (3×100 mL) and the combined organic layers washed with brine (2×50 mL) and dried over Na2SO4. After evaporation of the solvent, the product was isolated by flash column chromatography eluting with 0% to 50% ethyl acetate/hexanes to give 1.6 g of the title compounds as a light yellow oil.

1. temperaturewith heating over a period of 30 min
2. temperaturecooled to −30° C.
3. temperatureThe temperature was maintained at −30° C. for 1 h
4. temperatureslowly raised to room temperature over a period of 3 h
5. customThe excess Grignard was destroyed by the careful addition of 200 mL saturated aqueous NH4Cl
6. extractionThe mixture was extracted with ethyl acetate (3×100 mL)
7. washthe combined organic layers washed with brine (2×50 mL)
8. dry with materialdried over Na2SO4
9. customAfter evaporation of the solvent
10. customthe product was isolated by flash column chromatography
11. washeluting with 0% to 50% ethyl acetate/hexanes