Nitrous oxide ions, decomposition

Let us consider first isovalent cations. MgO can dilute ions of similar size, as for instance Ni or Co forming NiO-MgO and CoO-MgO solid solutions with an infinite range of composition. The effect of progressively replacing Mg by Ni or similar cations (Co ", Cu ) on the surface properites has been investigated both experimentally [83,177,178] and theoretically [179,180]. The presence of Ni cations diluted in the MgO matrix results in an efficient catalyst for nitrous oxide, N2O, decomposition this has been attributed to the different bond strength of the Ni-0 and Mg-0 bonds at the surface [177]. Plane wave calculations on Ni-doped MgO have shown that the presence of Ni atoms on the... 

Kummer [19], Friedman and Biegeleisen [20] studied the decomposition of ammonium nitrate labelled withI5N [15N]H4 [14N]03. The completely anhydrous salt did not decompose until 300°C. Only sublimation took place. But a trace of water initiated decomposition at 180°C. The main products of the reaction were NzO and water (according to the eqn. (4)) and with the labelled salt, nitrous oxide [14N] [15N]0 was produced showing that the gas was formed by the interaction of the two ions in the molecule. They also showed that with ordinary ammonium nitrate and H2180, no N2I80 was formed, indicating that the water had a purely catalytic effect. 

Thus, copper and platinum give similar results the nitrite formation is greater with iron, nickel, and cobalt, and the nitrate formation less. The gases were mainly nitrous oxide and nitrogen with a small proportion of oxygen. N. D. Zelinsky and S. G. Krapiwin showed that the decomposition of hydroxylamine into acid and base does not occur in soln. with methyl alcohol as solvent. J. Tafel showed that an aq. soln. of hydroxylamine sulphate in presence of 20-50 per cent, of sulphuric acid is not reduced at a copper cathode. O. Flaschner observed some reduction in dil. sulphuric acid soln. J. Tafel and H. Hahl found that reduction always takes place when the sulphuric acid cone, in the layer of electrolyte in contact with the cathode is reduced beyond a certain point, and when there is no excess of acid in other words, when hydroxylamine sulphate itself is electrolyzed, the reduction is quantitative. These results are most readily accounted for on the view that only free hydroxylamine (produced in this case by partial hydrolysis of the sulphate), but not the hydroxylammonium ion, NH3OH, is reduced at a copper... 

There are many examples involving ammonium ions for instance, the decomposition of ammonium nitrate to nitrous oxide. Ammonium... 

An alternative mechanism was suggested by Oxley and coworkers. [59] They concluded that above 160°C the decomposition occurs by a free-radical mechanisms while an ionic mechanism is important below this temperature. The decomposition of ADN leads to nitrous oxide, nitric acid or nitrate and nitrogen gas. It was assumed that the first step in ADN decomposition is hydrogen transfer to form ammonia and dinitramic acid. Several proposed decomposition pathways for ADN decomposition that involve conversion of the dinitramide ion to N2O have been proposed but they await confirmation.[59]... 

Transition metal ions dispersed in spinel matrices were studied for the decomposition of nitrous oxide (15,16) however, there have been no reports on solid solutions of spinels for augmenting catalytic activity and stability in oxidation reactions. This is a report on work done with transition metal oxide spinels to minimize the first two forms of degradation through formation of solid solutions. Included are studies of various reaction processes involved in catalytic treatment of automotive exhaust gases. 

Short reference will be made to the decomposition of benzylazoxy-4-toluenesulfo-nate (7.21) studied by Maskill s group (Maskill, 1980 Maskill and Jencks, 1984,1987 Conner and Maskill, 1988 Gordon and Maskill, 1989, and further papers mentioned there). As shown in (7-9), this reaction also leads to solvolysis products of car-bocations, but with nitrous oxide as a leaving group rather than an N2 molecule. The intermediacy of an alkoxydiazonium ion (7.22) is postulated on the observation that considerable amounts of benzyl thiocyanate (7.23) and some benzaldehyde... 

Although this reaction does not lead to an alkanediazonium ion, it is obvious that it is another method that is closely related to the deamination pathways discussed in this section. The azoxytoluenesulfonate method is related to the use of N-nitroamides as a source for carbocations because the leaving group is also nitrous oxide (7-10). The A -nitroamide decomposition was used extensively by White and coworkers in the 1960 s and 1970 s (see White and Grisley, 1961 White et al., 1973 White and Field, 1975, and literature cited there). N-Nitro carbamates (7.25, R = OR") can also be used. 

An n.m.r, study of B(OMe)3 in methanol shows fast methyl exchange, with / (MeOH)/ (MeOD)= l. Reaction is catalysed by both acids and bases. The decomposition of the A-nitrosohydroxylamine-A-sulphonate anion to nitrous oxide and sulphate ion is catalysed by boric acid ... 

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