Iodination of aromatic rings

Answer Procedure V-5, the iodination of aromatic rings can he modified if tile aromatic ring is a phenol. We merely have to treat the phenol with lj. 

Aromatic iodides are important intermediates in the synthesis of functional materials and biologically active compounds.Although various methods for the synthesis of aromatic iodides have been developed, direct iodination of aromatic rings serves as one of the most straightforward routes. 

Direct fluorination or iodination of aromatic rings is also possible but requires special methods. 

Chlorination of alcohols by Thionyl Chloride the preparation of acyl chlorides from lactones and anhydrides, and the bromi-nation and iodination of aromatic rings by Benzyltrimethylammo-nium Tribromide and Benzyltrimethylammonium Dichloroio-date, respectively, are all effectively catalyzed by the presence of ZnCl2. In addition, ZnCl2 acts as a source of chloride for the halogenation of primary, secondary, and allylic alcohols using Triphenylphosphine-DiethylAzodicarboxylate. ... 

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