反应详情

Under argon, 3.79 g (14.5 mmol) of 5,5,5-trifluoro-3-methyl-2-(4-methylphenyl)pentanoic acid were dissolved in 60 ml of THF at room temperature, and 27 μl (0.22 mmol) of a 1 M boron trifluoride/diethyl ether complex solution were added. 3.828 g (17.48 mmol) of tert-butyl 2,2,2-trichloroethanimidoate were then metered in a little at a time, and the mixture was stirred at room temperature overnight. After the reaction had gone to completion (monitored by TLC; mobile phase cyclohexane/ethyl acetate 2:1), 2 g of solid sodium bicarbonate were added with vigorous stirring of the reaction solution. The reaction mixture was then filtered, and the solvent was removed under reduced pressure. The crude product was purified chromatographically on silica gel (mobile phase cyclohexane/ethyl acetate 5:1). This gave 3.25 g (10.27 mmol, 71% of theory) of the title compound as a colorless oil.

1. addition27 μl (0.22 mmol) of a 1 M boron trifluoride/diethyl ether complex solution were added
2. additionwere added
3. stirringwith vigorous stirring of the reaction solution
4. filtrationThe reaction mixture was then filtered
5. customthe solvent was removed under reduced pressure
6. customThe crude product was purified chromatographically on silica gel (mobile phase cyclohexane/ethyl acetate 5:1)