Nitrogen trioxide nitrous anhydride

It is assumed that the mechanism of dissociation of nitrogen trioxide involves its separation into disproportionate amounts of the nitrosonium and nitrite ions  

Hence the formation of nitroso compounds (C-nitroso- and O-nitroso, i.e. nitrous acid esters) is possible. 

Nitrogen trioxide combines with boron trifluoride to form a complex salt, the structure of which, as assumed by G. B. Bachman and Hokama [104], should 

In consequence of its dual form the compound can act both as a nitrosating (diazo-tizing) and as a nitrating agent. 

Bachman and Hokama found that benzene was nitrated by the complex in 5-6% yield, whereas nitrotoluene formed gum. If, however, toluene is nitrated in nitroethane, then 56% of o- nitrotoluene, 1% of p- nitrotoluene and 3% of 2,4-dinitrotoluene are obtained, o- Nitrotoluene can be nitrated to 2,4-dinitro-toluene by the complex in 40% yield. 

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As would be expected from a substance of this nature, water causes rapid decomposition into sulphuric acid and the decomposition products of nitrous acid, whilst sulphuric acid dissolves the substance with formation of nitrosulphonic acid, which crystallises on cooling. With sulphur trioxide the anhydride yields a stable complex of composition 2(S2N209).S03.1 Gaseous ammonia causes the anhydride to melt and decompose slowly with formation of nitrogen and ammonium hydrogen sulphate ... 

Nitrogen trioxide and nitrogen pentoxide are the anhydrides of nitrous acid and of nitric acid. They are difficult to prepare and are unstable. 

The blue gas dinitrogen trioxide, N203 (Fig. 15.6, 1), in which the oxidation number of nitrogen is +3, is the anhydride of nitrous acid, HN02, and forms that acid when it dissolves in water ... 

Nitrous acid can be produced in aqueous solution by mixing its anhydride, dinitrogen trioxide, with water. The oxidation number of nitrogen in HNO2 is -i-3. N20s(g) -1- H20(l) 2HN02(aq)... 

Dinitrogen trioxide, N2O3, can be obtained as a blue liquid by cooling an equimolal mixture of nitric oxide and nitrogen dioxide. It is the anhydride of nitrous acid, and produces this acid on solution in water ... 

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