Trioxodinitrate and Nitrogen Monoxide

The thermal decomposition of solid alkali metal trioxodinitrates is suggested to involve the intermediate formation of hyponitrite. The N nmr spectrum of the trioxodinitrate anion shows that protonation occurs at the nitrosyl nitrogen atom as in equation (12). This observation has 

Decomposition of sodium trioxodinitrate in the presence of [Ni(CN)4] gives [Ni(CN)3(NO)] by direct displacement of CN by NO . The NO produced by the reaction between nitrogen monoxide and hydroxylamine is also trapped by tetracyanonickelate(II) in a direct displacement reaction, but the trapping efficiency differs in the two cases. This may reflect the difference in the electronic states of NO formed in the two reactions, NO from HNO being a singlet species and NO from NOH being a triplet.  

The redox chemistry of nitrogen monoxide has attracted further attention partly in an environmental context. It is reduced by Fe(II) to give HNO and hence N2O. Further reduction to N2 does not occur below pH The first stage is the formation of the Fe(II) nitrosyl complex, 

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