反应详情

bromine (32.5 g≡10.4 ml) was added over 15 minutes to a stirred mixture of (±)-1-(3-trifluoromethylphenyl)-ethanol [38 g, described by Overberger et al., Org. Synth. Coll. 3, 200 (1955)], triphenylphosphine (56 g) and dry dimethylformamide (200 ml) in an atmosphere of nitrogen. The temperature of the mixture was maintained at 40°-50° C. by ice-cooling. Further bromine was added dropwise to give a permanent orange colour and after stirring for 15 minutes the mixture was poured into a mixture of ice-water (1 liter) and hexane (500 ml). The mixture was filtered and the solid material was washed well with hexane. The hexane solutions were combined, washed with water (4×100 ml), dried over sodium sulphate and distilled to give (±)-1-(3-trifluoromethylphenyl)ethyl bromide, b.p. 98°-105° C./15 mmHg, as a clear mobile oil.

1. temperatureThe temperature of the mixture was maintained at 40°-50° C. by ice-
2. temperaturecooling
3. customto give a permanent orange colour
4. filtrationThe mixture was filtered
5. washthe solid material was washed well with hexane
6. washwashed with water (4×100 ml)
7. dry with materialdried over sodium sulphate
8. distillationdistilled