Anodic Substitution Reactions with Aromatic Hydrocarbons

Anodic Substitution Reactions with Aromatic Hydrocarbons 

As with the electro-oxidation of aliphatic hydrocarbons, several pathways may be involved in anodic reactions of aromatic molecules (a) direct electron transfer from the aromatic substrate to form cationic species, (b) reaction of 

Furthermore, and again as with alkanes and alkenes, the mechanism of the oxidation and the products of the reaction will depend upon factors such as the electrolyte, the electrode material, the electrode potential, the stability of the various intermediates, and the nucleophilicity of the anion species. 

It appears that many of the anodic reactions of aromatic hydrocarbons— and particularly those in nonaqueous electrolytes—proceed by way of the formation of a cation radical  

Indeed the polarographic half-wave potential is a direct measure of the ease with which the electron transfer is effected, provided that it is the potential of the reversible, one-electron process that is measured. Available data for the half-wave potentials for the oxidation of series of aromatic hydrocarbons is extensive and series of the early 1/2 values were shown to 

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Anodic Substitution Reactions with Aromatic Hydrocarbons... 

Reactions between aromatic hydrocarbon radicabcations and cyanide ions, with few exceptions, give low yields of nuclear substitution products [76], In some cases, better results have been obtained by anodic oxidation of the aromatic compound in an emulsion of aqueous sodium cyanide and dichloromethane with tetra-butylammonium hydrogen sulphate as a phase transfer agent [77, 78]. Methoxy-benzenes give exceptionally good yields from reactions in acetonitrile containing tetraethylammonium cyanide, sometimes with displacement of methoxide [79, 80]... 

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