Radical Conversions of p-benzoquinones in Reactions with NO

A doublet splitting of the triplet components with ajj =0.17 mT is also observed because of the hydrogen atom adjacent to the nitrogen [88]. 

Oxyaminoxyl radicals with similar ESR parameters have heen detected in reactions of NO with phorone [70] in which it is believed that these radicals are produced by 

In this connection, the analogous structure of oxyaminoxyl radicals in TBQ seems the most preferable. 

Obviously, iminoxyl and acyl(alkyl)aminoxyl radicals cannot be formed by the direct interaction of NO with the double bonds of the quinines, but these radicals are produced as a result of thermal conversions of primary oxyaminoxyl radicals most likely because of the strong angular strain arising from their bicyclic structure. Oxyaminoxyl radicals can decompose, giving alkoxyl radicals, which subsequently break down, leading to the destruction of the quinine structure with the formation of acyl radicals containing nitroso groups  

The cyclopropanone fragments of radicals appear to be unstable and [91], and elimination of CO leads to the following conversion  

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