Hydrochloric Acid → Benzene, 1-chloro-4,5-difluoro-2-(trichloromethyl)-

Participants

Reaction Steps

Into a 200 ml four-necked flask equipped with a stirrer, a reflux condenser, a thermometer and a dropping funnel, 97 ml (1 mol) of carbon tetrachloride and 26.7 g (0.2 mol) of aluminum chloride were charged, and 14.9 g (0.1 mol) of 1-chloro-3,4-difluorobenzene was gradually dropwise added over a period of 1.5 hours under reflux so that hydrochloride gas was slowly generated. The generated hydrochloride gas was absorbed by an aqueous sodium hydroxide solution. After completion of the dropwise addition, the mixture was reacted for 10 minutes. After cooling to room temperature, the reaction mixture was poured into 300 ml of ice water. The organic layer was separated and washed with 100 ml of water, then with 100 ml of 5% of sodium hydrogen carbonate aqueous solution and further with 100 ml of water. After distilling off carbon tetrachloride, the residue was distilled under reduced pressure to obtain 17.4 g (yield: 65.4%) of 2-chloro-4,5-difluorobenzotrichloride. Boiling point: 104°-106° C./8 mmHg, nD20 1.540; purity: 98.2%

Provenance & Evidence