反应详情

2.25 g (8.2 mmol) of ethyl 4,4,4-trifluoro-3-methyl-2-(4-methylphenyl)butanoate, 1.53 g (8.6 mmol) of N-bromosuccinimide and 67 mg (0.41 mmol) of 2,2′-azobis(2-methylpropanenitrile) in 36 ml of trichloromethane were stirred under reflux overnight. After the reaction had gone to completion, the succinimide was filtered off and the filter residue was washed with dichloromethane. The filtrate was concentrated under reduced pressure. The crude product was purified chromatographically on silica gel (mobile phase cyclohexane/ethyl acetate 40:1). This gave 2.667 g (7.5 mmol, 92% of theory) of a yellowish oil.

1. temperatureunder reflux overnight
2. filtrationthe succinimide was filtered off
3. washthe filter residue was washed with dichloromethane
4. concentrationThe filtrate was concentrated under reduced pressure
5. customThe crude product was purified chromatographically on silica gel (mobile phase cyclohexane/ethyl acetate 40:1)