Mechanisms of free-radical aromatic substitution

✍ Scribed by D.H. Hey; M.J. Perkins; Gareth H. William

• Publisher: Elsevier Science
• Year: 1963
• Tongue: French
• Weight: 367 KB
• Volume: 4
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)90654-9

✦ Synopsis

In a recent communication, Ellel, Eberhardt, Simamura and Meyerson,' while recognising a common homolytic substitution pattern in the arylation of aromatic compounds with three sources of aryl radicals, namely diarpfll peroxides, acylarylnitrosamines, and arylazotriarylmethanes, regarded the first of these souroes as unique among them in that arylcyclohexadienyl radicals (II) (See below) were thought to exist in the free state as intermediates in the arylation process with diaroyl peroxides. This conclusion was reached by the application of three stated criteria for the existence of these radicals, namely (a) the formation of dihydrobiaryls as byproducts of these reactions; (b) an apparent isotope effect in the arylation of benzene-g 88 computed from the deuterium content cf the bimrl famed, due, at least in part, to isotopic discrimination in the 1 EL. ELlel,Y. iberbznit,O.Sirrnn sla S.MOyere~,~~ Letters, 7u9 (W) .

4. 6

Free-radical aromatic substitution No.7 disproportionation of arylcyclohexadienyl radicals;