反应详情

A mixture of 100 parts of 3'-bromo-2'-methylacetophenone, 30 parts of ethylene glycol, 320 parts of anhydrous toluene and 2 parts of p-toluenesulfonic acid is stirred and refluxed for 4 hours with water-separator. A second fraction of 30 parts of ethylene glycol is added and stirring at reflux is continued for 18 hours. The reaction mixture is cooled and stirred for 30 minutes with 5 parts of sodium carbonate. The organic layer is separated, washed twice with water, dried and evaporated. The residue is distilled twice, yielding 2-(3-bromo-o-tolyl)-2-methyl-1,3-dioxolane; bp. 148°-150° C at 12 mm. pressure.

1. stirringstirring
2. temperatureat reflux
3. temperatureThe reaction mixture is cooled
4. customThe organic layer is separated
5. washwashed twice with water
6. customdried
7. customevaporated
8. distillationThe residue is distilled twice