Nitrous acid decomposition, studies

More recently, Kirmse and his coworkers found two other deamination reactions where product studies indicated the intermediate formation of radicals, namely the nitrous acid decompositions of 2-aminobutylnitrile (Bunse and Kirmse, 1993) and of the epimeric 2-aminonorbornyl-2-carbonitrile (Kirmse et al., 1993b). Like 2-amino-2-methylpropylnitrile (7.59), these compounds are characterized by a CN group at the same C-atom as the NH2 group. 

A yellow solution is formed when nitrous acid is added to thiosulphate ion in water84. This is believed to be due to the formation of nitrosyl thiosulphate [O3SSNOI, although this has not been isolated and even in solution decomposition is fairly rapid. The equilibrium constant for its formation Wxno is 1.66 x 107 dm6 mol 2 at 25 °C and the UV-visible absorption spectrum is very similar to that of other S -nitroso compounds85. The rate constant for its formation is very large and is believed to represent a diffusion controlled process. Thiosulphate ion does appear to catalyse nitrosation but, over the range studied... 

It is necessary to take into consideration the fact that the decomposition of nitric esters has an autocatalytic character water and nitrogen dioxide formed during the decomposition lead to the formation of nitric and nitrous acids which accelerate the reaction of decomposition of the nitric ester. The influence of nitric acid on the rate of decomposition of nitroglycerine was studied by Roginskii [79] and is described below. 

The kinetics of reaction of a number of A-nitrosothiols (334) in water with mercury(II) salts have been reported. Reaction is first order in both reactants and the products are nitrous acid and the corresponding thiol-Hg2+ complex. The mechanism involves slow attack by water at the nitrogen atom in the complex.300 The same group has also studied the copper(II)-catalysed decomposition of the, -nitrosothiols derived from penicillamine, cysteamine, thiomalic acid, A -acetylpenicillaminc, and cysteine.301... 

Alkyldiazonium Ions. The intermediacy of alkyldiazonium ions in a variety of organic reactions is well established.450 152 They are common intermediates in the acid-catalyzed decomposition of diazo compounds and the nitrous acid-induced deamination of aliphatic primary amines. The evidence for RN2+ (R = alkyl) intermediates come from both rate data and product analysis studies. However, direct investigation of alkyldiazonium ions has been difficult due to their instability. 

A kinetic study has been reported recently for the nitrosation of many symmetrical tertiary amines in aqueous acid-acetate buffers (Gowenlock et al., 1979). One experimental difficulty in tertiary amine nitrosations generally is that the reactions are much slower than for the analogous secondary amines, and are more conveniently studied at a higher temperature, typically 75°C, where the decomposition of nitrous acid is quite rapid. In this study, rate constants were obtained from the less accurate method of initial rate measurements. Nevertheless, for acidities less than pH 3.1, rate eqn (16) was established. The acid dependence is complicated by the protonation of the... 

A careful and detailed study of the solubility and decomposition kinetics of nitrous acid in aqueous solution has appeared. This is part of an excellent program of work on atmospheric chemistry, and provides valuable quantitative data, particularly in terms of solubility parameters. Stanbury et have bubbled N0 2 in a stream of N2 into alkaline aqueous solutions of Na N02, and determined the amount of. This is a difficult experiment to do well, and has produced... 

A study of the kinetics of the decomposition of ammonium perchlorate has been made by Bircumshaw and Newman [5]. The gaseous products, up to a temperature of 300°C, were found to be oxygen, chlorine, chlorine dioxide, nitrous oxide, nitrogen tetroxide, chlorine dioxide, hydrochloric acid, perchloric acid and water. The total volume of oxygen and nitrogen produced by unit weight of the solid showed practically no variation up to about 300°C. 

Regardless of the particular mechanism, if the activation process is accomplished through the absorption of single or multiple frequencies, then a marked increase in the radiation density of these frequencies should cause a change in reaction velocity. The decomposition of ozone and nitrous oxide have been studied from this point of view and are reported here. Since the inception of this work, it has been found elsewhere3 that the oxidation of alcohol vapor and the decomposition of nitrogen pentoxide and hydrochloric acid were not affected by infra-red radiation. The present work confirms these results for two additional reactions. 

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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