反应详情

12.7 parts of the 2-(4'-chloro-2'-difluoromethoxyphenyl)-2-methyl-4-ethyl-1,3-dioxolane prepared in (a) are dissolved in 100 ml of abs. chloroform and the solution is warmed to 30° C. Under irradiation with a 150 watt spot lamp, 7.3 parts of bromine in 30 ml of abs. chloroform are added dropwise over 1 hour and the reaction mixture is then stirred for 2 hours at room temperature. The reaction mixture is then washed with 2×100 ml of water, dried over sodium sulfate, and filtered. The solvent is removed by evaporation and the oily residue is purified by high vacuum distillation; b.p. 113°-115° C./0.05 mbar.

1. dissolutionare dissolved in 100 ml of abs
2. washThe reaction mixture is then washed with 2×100 ml of water
3. dry with materialdried over sodium sulfate
4. filtrationfiltered
5. customThe solvent is removed by evaporation
6. distillationthe oily residue is purified by high vacuum distillation