反应详情

251.1 g of 3-methoxypropyltriphenylphosphonium bromide are added to a solution, stirred at 5°, of 110.8 g of sodium bis(trimethylsilyl)amide in 1200 ml of tetrahydrofuran. The reaction mixture is further stirred for 45 minutes at 0° and then a solution of 100 g of 5-bromo-o-anisaldehyde in 1000 ml of tetrahydrofuran is added dropwise thereto. The reaction mixture is stirred for a further 1 hour at 0°. Then, at 0° C., 1 litre of a saturated ammonium chloride solution is added dropwise. After concentration, the residue is extracted 4 times with ethyl acetate. The organic phases are washed with water and saturated sodium chloride solution and concentrated by evaporation. The residue is purified by FC (500 g of silica gel, hexane/ethyl acetate=5:1). Distillation under a high vacuum yields the title compound: Rf (hexane/ethyl acetate=4:1)=0.61.

1. stirringThe reaction mixture is stirred for a further 1 hour at 0°
2. concentrationAfter concentration
3. extractionthe residue is extracted 4 times with ethyl acetate
4. washThe organic phases are washed with water and saturated sodium chloride solution
5. concentrationconcentrated by evaporation
6. customThe residue is purified by FC (500 g of silica gel, hexane/ethyl acetate=5:1)
7. distillationDistillation under a high vacuum