反应详情

A suspension of methoxymethyl triphenylphosphonium chloride (6.69 g, 19.5 mmol) in THF (200 mL) was cooled to ca. −20° C. n-BuLi (2.5 M in hexanes, 7.2 mL, 18 mmol) was added in portions over 5 min and the orange-red reaction mixture was stirred for an additional 15 min. 4-difluoromethoxybenzaldehyde (2.58 g, 15.0 mmol) in THF (50 mL) was added at −10° C. and the reaction mixture was stirred at this temperature for 30 min and then at room temperature for 19 h. Water (100 mL) was added and the mixture was concentrated under reduced pressure. The remaining aqueous phase was extracted with ethyl acetate (2×100 mL) and the combined organic phase was washed with water (2×100 mL) and brine (100 mL), dried over Na2SO4, and concentrated in vacuo. The crude product was purified by three times repeated chromatography on silica gel. (Horizon™, flash system from Biotage™. Column: Flash 40+M, 40×150 mm. Eluent: 3% ethyl acetate in heptane. Combination of pure fractions and concentration in vacuo afforded 1.60 g (53%) of the title compound as a colourless oil.

1. additionwas added in portions over 5 min
2. stirringthe reaction mixture was stirred at this temperature for 30 min
3. waitat room temperature for 19 h
4. concentrationthe mixture was concentrated under reduced pressure
5. extractionThe remaining aqueous phase was extracted with ethyl acetate (2×100 mL)
6. washthe combined organic phase was washed with water (2×100 mL) and brine (100 mL)
7. dry with materialdried over Na2SO4
8. concentrationconcentrated in vacuo
9. customThe crude product was purified by three times
10. concentrationCombination of pure fractions and concentration in vacuo