Nitrogen monoxide disproportionation

The reactions of nitric oxide involve either oxidation or reduction (or both simultaneously in disproportionation and decomposition). Except for oxidation, these reactions of nitric oxide require catalysts for them to proceed at significant rates. An important stimulus to studying these catalyzed reactions lies in the environmental hazards posed by oxides of nitrogen, of which NO is the parent member, as discussed at the beginning of this section. Particular attention in the area of metal complex catalyzed reactions has focused in the last five years on the reduction of nitric oxide by carbon monoxide, (113). 

For this compound, which is closely related to the isoelectronic Hg[Fe(CO)3NO]2 (45) (Section IX) and to Hg[Mn(CO)5]2 (VII, 79), a convenient method of preparation in aqueous solution was discovered in conjunction with E. O. Fischer (46). Moreover, we could make IIg[Co(CO)4]2 react, like Co2(CO)8, with ligands either with substitution of carbon monoxide and formation of Hg[Co(CO)3L]2 (L = PR3, AsR3, SbR3), or by valence disproportionation of cobalt (VII, 80) using nitrogen bases or isonitriles, e.g.,... 

The methyl disproportionation reaction appeared to occur at the higher temperatures. Hydrogen-rich species—methane and hydrogen— were observed in the gaseous products. In the absence of carbon monoxide or other multiple-bonded gaseous molecules, it may be assumed that an amine or nitrogenous species was the hydride donor, and that hydrogen-deficient moieties (nitriles, polyunsaturates, etc.) remained as adsorbed coke (0.2 wt % N, 2.2 wt % C) on the zeolite surface. 

Dinitrogen monoxide (N2O), formed by disproportionation of dinitrogen trioxide (N2O3), is easily oxidised by oxygen to nitrogen... 

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