反应详情

To a suspension of the phosphonium salt from Step 5 (409 mg, 0.85 mmol) in dry THF (5 mL) at -78° C. was added a solution of potassium ten-butoxide (0.716 mL, 1M solution in THF). The mixture was warmed to room temperature for 30 min, and then cooled to -78° C. before adding the aldehyde from Step 17 (300 mg, 0.7 mmol). The mixture was stirred at -78° C. for 30 min, warmed to 0° C. for 15 min. Aqueous NH4OAc was added and the mixture was extracted with EtOAc. The organic extract was washed with brine, dried over MgSO4, and concentrated to an oil. Chromatography of the crude oil on silica gel (eluted with 20% EtOAc in hexane) gave 420 mg (98%) of the title compound.

1. temperaturecooled to -78° C.
2. temperaturewarmed to 0° C. for 15 min
3. extractionthe mixture was extracted with EtOAc
4. extractionThe organic extract
5. washwas washed with brine
6. dry with materialdried over MgSO4
7. concentrationconcentrated to an oil