Alkoxyl radical reactions with nitrogen

Alkyl nitrates and alkyl nitrites can be formed by the reaction of alkoxyl radicals (RO ) with nitrogen dioxide and nitric oxide, respectively ... 

The antioxidant role of NO comes Ifom its reaction with oxygen, carbon and nitrogen centred radicals and can be seen to have a scavenger role under a range of conditions [112]. This is because of the unpaired electrons of NO which react rapidly with alkoxyl and alkyl hydroperoxyl radicals at near diffusion reaction rates (2x10 M s [113]). It is these reactions that have been suggested to have a modulatory role in enzyme- or metal-catalysed... 

Peroxy-linked dimers are also formed from linoleate hydroperoxides in the presence of free radical initiators and copper palmitate, and carbon-carbon linked dimers in the presence of copper catalysts. Decomposition of methyl linoleate hydroperoxides at 210°C under nitrogen produces mainly carbon-carbon linked dimers (82%), monomers with loss of diene conjugation, volatile compounds (4-5%) and water. The resulting dimers contain carbonyl and hydroxyl groups and double bonds scattered between carbon 8 and carbon 10. Linoleate hydroperoxides can dimerize by one of the termination reactions discussed in Chapter 1. The termination reactions involving combination of alkyl, alkoxyl, or peroxyl radical intermediates produce dimers with carbon-carbon, carbon ether, or peroxy links. The carbon-carbon and carbon-oxygen linked dimers are favored at elevated temperatures and the peroxy-linked dimers at ambient temperatures. The peroxy-linked dimers may also decompose to the ether-linked and carbon-carbon linked dimers via the corresponding alkyl and alkoxyl radical intermediates. 

Extending an investigation of the double )S-scission reaction of alcohols with nitrogen substitution at the )3-carbon (Scheme 37), Japanese authors have reported that the intermediate alkoxyl radical can be generated more effectively photochemically, using hypoiodite, or oxidatively, with lead tetraacetate, rather than by the earlier method of nitrite ester irradiation. 

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