Arenes with diaroyl peroxides

The thermal decomposition reaction of a diaroylperoxide, (ArCOO)2, in a liquid arene, Ar, furnishes a biaryl, Ar-Ar [101-107]. At elevated temperatures the diaroyl peroxide dissociates by the homolytic pathway to generate the arylcarboxy-radicals, ArCOO, which are prone to rapid decarboxylation forming the aryl radicals, Ar. The latter react with the arene, e.g. benzene, by the free-radical arylation mechanism, closely similar to the classical Gomberg-Bachmann-Hey reaction pathway, to give the biaryls, Ar-Ar, in moderate to good yields [101-103], Scheme 28. 

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