反应详情

At 10° C., 5.99 g (32.7 mmol) sodium bis(trimethylsilyl)amide are added dropwise to a solution of 13.5 g (27.3 mmol) of the compound from Example 47A in 145 ml of dioxane. The mixture is stirred at this temperature for 1 h. A solution of 2.40 g (54.5 mmol) of acetaldehyde in 5 ml of dioxane is then added, and the reaction is stirred at RT for 1 h. 400 ml of water are then added, the mixture is extracted three times with dichloromethane and the combined organic phases are washed twice with saturated aqueous sodium chloride solution. After drying over sodium sulphate and subsequent filtration, the solvent is removed under reduced pressure. The product is purified by chromatography on silica gel (mobile phase: cyclohexane/ethyl acetate=40:1). This gives 5.2 g (100% of theory) of the desired product as an E/Z isomer mixture.

1. stirringthe reaction is stirred at RT for 1 h
2. extractionthe mixture is extracted three times with dichloromethane
3. washthe combined organic phases are washed twice with saturated aqueous sodium chloride solution
4. dry with materialAfter drying over sodium sulphate and subsequent filtration
5. customthe solvent is removed under reduced pressure
6. customThe product is purified by chromatography on silica gel (mobile phase: cyclohexane/ethyl acetate=40:1)