Triphenylchloromethane from benzene and carbon tetrachloride

In the apparatus used for the preparation of benzophenone 60 g. of fresh active aluminium chloride are gradually added to a mixture 

For purification the still yellow crude product is dissolved in very little warm benzene, four volumes of light petrol are added, and crystallisation is induced by cooling in ice and stirring with a glass rod. The crystals are washed with cold petrol ether. 

Distillation in a high vacuum also yields a very pure preparation (Lecher). 

Finely powdered anhydrous zinc chloride (2 g.) is added to a solution of 5-5 g. of resorcinol and 3 g. of acetonitrile in 25 c.c. of absolute ether, the mixture is kept cool in ice and saturated with hydrogen chloride. After standing for some hours in a closed vessel 

Both acid chlorides and alkyl chlorides react with aromatic compounds in the presence of aluminium chloride, zinc chloride, or ferric chloride in such a way that HC1 is eliminated and the acyl or alkyl group enters the ring  

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