反应详情

At 10° C., 5.99 g (32.7 mmol) of sodium bis(trimethylsilyl)amide are added dropwise to a solution of 13.5 g (27.3 mmol) of the compound from example 35A in 145 ml of dioxane. The mixture is stirred at this temperature for 1 h. Then a solution of 2.40 g (54.5 mmol) of acetaldehyde in 5 ml of dioxane is added and the mixture is stirred at RT for 1 h, then admixed with 400 ml of water and extracted three times with dichloromethane, and the combined organic phases are washed twice with saturated aqueous sodium chloride solution. After drying over sodium sulfate and subsequent filtration, the solvent is removed under reduced pressure. It is purified by means of chromatography on silica gel (eluent: cyclohexane/ethyl acetate=40:1). This affords 5.2 g (100% of theory) of the desired product as an E/Z isomer mixture.

1. stirringthe mixture is stirred at RT for 1 h
2. extractionextracted 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 sulfate and subsequent filtration
5. customthe solvent is removed under reduced pressure
6. customIt is purified by means of chromatography on silica gel (eluent: cyclohexane/ethyl acetate=40:1)