Dinitrogen tetroxide structure

Iron, trinitrato(dinitrogen tetroxide)-structure, 1,28 Iron, tris(acetylacetone)-electron recording system, 6,127 structure, 1, 65 Iron, tris(bipyridyl)-... 

Unlike nitrogen monoxide, nitrogen dioxide has properties more typical of an odd electron molecule. It is a coloured (brown), reactive gas which dimerises to the diamagnetic colourless gas dinitrogen tetroxide, N2O4. in which the odd electron is paired. The structure of dinitrogen tetroxide can be represented as a resonance hybrid of ... 

Outline the laboratory preparation of a sample of dinitrogen tetroxide. Describe and explain what happens when it is heated from 290 K to 900 K. Suggest electronic structures for dinitrogen tetroxide and the other nitrogen-containing molecules formed from it on heating to 900 K. Point out any unusual structural features. 

Recently, nitration of organolithiums and Grignards with N204 has been developed for the preparation of certain kinds of nitro compounds (Eqs. 2.14 and 2.15).31 The success of this process depends on the reaction conditions (low temperature) and the structure of substrates. For example, 3-nitrothiophene can be obtained in 70% overall yield from 3-bromothiophene this is far superior to the older method. 3-Nitroveratrole cannot be prepared usefully by classical electrophilic nitration of veratrole, but it can now be prepared by direct o>7/ o-lithiation followed by low-temperature N204 nitration. The mechanism is believed to proceed by dinitrogen tetroxide oxidation of the anion to a radical, followed by the radical s combination. 

In developing the reactivity scale, Nielsen first investigated the transformation rates of 25 PAHs and four derivatives of anthracene in water-methanol-dioxane solutions, taken as a model of wet particles, and containing small amounts of dinitrogen tetroxide and nitric and nitrous acids. The measured half-lives and relative rates are shown in Table 10.29. The range of reactivities in solution for PAHs of different structures is remarkable, from 100,000 (arbitrarily set) for an-thanthrene (XXXII) to <0.2 for the least reactive compounds ... 

Nitrogen dioxide (NO2), which is also an odd-electron molecule, has a V-shaped structure. The reddish brown, paramagnetic NO2 molecule readily dimerizes to form dinitrogen tetroxide,... 

The type and the stereochemistry of the products depends on the structure of the alkene and the experimental conditions. The use of oxygen as a carrier gas for dinitrogen tetroxide affects the course of the reaction in various ways, depending on the alkene, but it especially prevents reduction of dinitrogen tetroxide to dinitrogen trioxide and thereby permits a cleaner product mixture to be obtained, or it can divert the reaction course toward the formation of /(-nitro nitrates115. 

What are possible electronic structures for dinitrogen tetroxide ... 

It is a surprising fact that the species NO2+ and N02 (Equation 2) have never been recognized as free ions in liquid dinitrogen tetroxide, although the latter would appear to dissociate heterol) cally in its addition compounds with strong electron acceptors. The 1 to 1 addition compound with boron trifluoride has been shown to have the structure N02+[BF3.N02] , and its powerful nitrating properties are consistent with the presence of the NO2+ ion (17,51). 

Iron Pentacarbonyl. In its reactions with liquid dinitrogen tetroxide this compound follows the pattern outlined above, and the remarks on reactions of nickel carbonyl probably apply here also. The solvate, Fe(N03)3.N204, is produced (4). This has the structure N0+[Fe(N03)4] in the solid state it is volatile without decomposition, and is believed to be a five-coordinate complex, Fe(N0)(N03)4, in the vapor state. We have not yet succeeded in isolating the simple trinitrate, Fe(N03)3, by removal of N2O4. 

A phenylfuroxan (or a structure which would now be written as such) was first reported by Scholl,190 and later by Wieland and Semper,19 by oxidation of a-phenylglyoxime (206) with dinitrogen tetroxide. Phenylacetylene and... 

Although nitrogen dioxide (NO2) is a stable compound, there is a tendency for two such molecules to combine to form dinitrogen tetroxide (N2O4). Why Draw four resonance structures of N2O4, showing formal charges. 

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