反应详情

160 g of 4-methyl-1,3-benzodioxole are added dropwise to 276 g of phosphorus pentachloride in 840 ml of carbon tetrachloride (prepared from phosphorus trichloride and chlorine), with stirring. Vigorous evolution of hydrogen chloride starts immediately. Towards the end of the reaction, 85 g of chlorine are passed in at about 20° C. and when the evolution of gas has ended, the mixture is then heated under reflux. By distillation, the phosphorus trichloride and carbon tetrachloride are recovered and the 4-methyl-2,2-dichloro-1,3-benzodioxole is then obtained at boiling point: 98°-99° C. (22 mbar).

1. customare passed in at about 20° C. and when
2. temperaturethe mixture is then heated
3. temperatureunder reflux
4. distillationBy distillation
5. customthe phosphorus trichloride and carbon tetrachloride are recovered