反应详情

500 parts of 2,4-dichlorotoluene (b.p.=198° to 200° C.) and 10 parts of anhydrous aluminum chloride were charged into a 1-liter four-necked flask provided with a reflux condenser, a thermometer, a stirrer and a dropping funnel. 397 parts of bromine was added dropwisely at 30° to 40° C. over a period of 5 hours. The reaction liquid was washed with warm water followed by separating the water layer, and then the oil layer was cooled. The separated crystals were filtered off, recrystallized from methanol to obtain 295 parts of 2,4-dichloro-5-bromotoluene having a melting point of 82.5° to 84.0° C.

1. customprovided with a reflux condenser
2. customThe reaction liquid
3. washwas washed with warm water
4. customby separating the water layer
5. temperaturethe oil layer was cooled
6. filtrationThe separated crystals were filtered off
7. customrecrystallized from methanol