Radical ions from arenes Birch reduction and arene oxidation

RADICAL IONS FROM ARENES BIRCH REDUCTION AND ARENE OXIDATION 

Early examples of electron transfer processes are shown in equations (2), (12), and (13). Birch in 1944 followed up the findings of Wooster, and demonstrated that Na metal and ethanol in ammonia reduce benzene, anisole, and other aromatics to 1,4-cyclohexadienes. Birch speculated about the mechanism of this reaction, but did not explicitly describe a radical pathway involving 55 (equation 87) until later, as described in his autobiography. Electron transfer from arenes was found by Weiss in 1941, who obtained crystalline salts of Ci4H]o from oxidation of anthracene.  

Reactions occurring by an electron transfer chain reaction in aliphatic systems were reported independently in 1966 by the groups of Kornblum and RusselP (equations 88, 89). These reactions involve initial transfer of an electron forming a radical anion 56b, which expels an anionic leaving group forming a neutral free radical, and this radical combines with radical 56a forming the product. 

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Radical ions from arenes Birch reduction and arene oxidation Electron transfer in aliphatic substitution 38 Electron transfer in aromatic substitution 38 Electrochemical electron transfer 39... 

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