Photolysis of aryl iodides

Another free-radical arylation method consists of the photolysis of aryl iodides in an aromatic solvent. Yields are generally higher than in 14-17 or 14-21. The aryl iodide may contain OH or COOH groups. The mechanism is similar to that of 14-17. The aryl radicals are generated by the photolytic cleavage ArI AR + T. The reaction has been applied to intramolecular arylation (analogous to the Pschorr reaction). A similar reaction is photolysis of an arylthallium bis(trifluoroacetate) (12-21) in an aromatic solvent. Here too, an unsymmetrical biaryl is produced in good yields. ... 

Another free-radical arylation method consists of the photolysis of aryl iodides in an aromatic solvent.339 Yields are generally higher than in 4-18 or 4-21. The aryl iodide may contain OH... 

The photolysis of aryl iodides is of use in the preparation of biphenyls, and the application of this reaction to the synthesis of phenanthrenes has already been discussed. Seven- and 8-membered nitrogen-containing heterocycles can also be obtained by an intramolecular arylation of this type photolysis of the iodoamine (345) affords, for example, 6,7-dihydro-5/ -dibenz[c,e]azepine (346).381... 

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