反应详情

温度

-70 °C

11.01 g (40 mmol) of dimethyl Boc-glutamate (Advanced Chemtech) were dissolved in 160 ml of tetrahydrofuran and cooled to −70° C. 88 ml (88 mmol) of a 1M solution of lithium bis(trimethylsilyl)amide in tetrahydrofuran were added dropwise at this temperature over a period of one hour, and the mixture was stirred at −70° C. for another 2 hours. 14.52 g (120 mmol) of allylbromide were then added dropwise, and after 2 h at this temperature, the cooling bath was removed and 200 ml of 2N aqueous hydrochloric acid and 400 ml of ethyl acetate were added. The organic phase was separated off, washed with water until neutral, dried over sodium sulphate and filtered, and the filtrate was concentrated. The crude product obtained in this manner was chromatographed in silica gel using a hexane/ethyl acetate gradient, and the appropriate fractions were combined and concentrated.

1. waitafter 2 h at this temperature
2. customthe cooling bath was removed
3. addition200 ml of 2N aqueous hydrochloric acid and 400 ml of ethyl acetate were added
4. customThe organic phase was separated off
5. washwashed with water until neutral,
6. dry with materialdried over sodium sulphate
7. filtrationfiltered
8. concentrationthe filtrate was concentrated