反应详情

温度

-70 °C

A solution of di-tert-butyl N-trityl-L-glutamate (1.99 g, 1.85 mmol) in THF (50 mL) was cooled to −70° C. and a 1.0 M solution of lithium bis(trimethylsilyl)amide 47 mL, 47 mmol) in THF was added slowly (over a period of 20 min). The solution was stirred for 2 h at −70° C., and allyl bromide (1.44 g g, 11.9 mmol) was added drop wise at −70° C. After stirring for 1.5 h, the reaction mixture was quenched with saturated aqueous solution of NH4Cl, and warmed up to room temperature, and concentrated under vacuum. The resulting aqueous solution was extracted with dichloromethane, the combined organic phase was washed with water and was dried over sodium sulfate. After filtration, the solution was evaporated and the crude product was purified by flash chromatography (silica, ethyl acetate/n-hexane) to give the di-tert-butyl 4-allyl-N-trityl-L-glutamate (1.01 g, 46%) as a mixture of (4S,4S)/(2S,4R) diastereoisomers.

1. stirringAfter stirring for 1.5 h
2. customthe reaction mixture was quenched with saturated aqueous solution of NH4Cl
3. temperaturewarmed up to room temperature
4. concentrationconcentrated under vacuum
5. extractionThe resulting aqueous solution was extracted with dichloromethane
6. washthe combined organic phase was washed with water
7. dry with materialwas dried over sodium sulfate
8. filtrationAfter filtration
9. customthe solution was evaporated
10. customthe crude product was purified by flash chromatography (silica, ethyl acetate/n-hexane)