Nitrogen trioxide, reaction with

Vanadium Carbide. Vanadium pentoxide [1314-62-17, V2O5, or vanadium trioxide [1314-34-7] VO3, are the most satisfactory oxides for the preparation of VC. Vanadium pentoxide is best prepared by igniting chemically pure ammonium vanadate [7803-55-6] NH VO, in the presence of moist oxygen to avoid reaction with nitrogen V2O3 is obtained by reduction of V2O3 with hydrogen (see Vanadium compounds). 

For the preparation of chlorides or bromides, the diazonium salt is decomposed with a solution of cuprous chloride or bromide in the corresponding halogen acid (Sandmeyer reaction). It is possible to prepare the aryl bromide from the diazonium chloride or sulfate. A variation Involves the use of copper powder and a mineral acid for the decomposition step (Gattermann reaction). Both procedures are illustrated by the syntheses of the isomeric bromotoluenes and chlorotoluenes. The usual conditions of the Sandmeyer reaction fail in the preparation of the chloro- and bromo-phenanthrenes. However, these compounds can be successfully obtained by the interaction of the diazonium compound with mercuric and potassium halides (Schwechten procedure). Another procedure for formation of aryl bromides involves treatment of the amine hydrobromide with nitrogen trioxide in the presence of excess 40% hydro-bromic acid. The Intermediate diazonium perbromide is then decomposed by heat. ... 

Polycarbonate is a thermoplastic material used in many applications, including microchips. The aromatic rings in the polycarbonate structure offer a relatively easy way to modify the PC surface by a direct sulfonation reaction. After cleaning with isopropyl alcohol, the polycarbonate surface is modified by reaction with sulfur trioxide at 50 °C for 10 min. Then it is rinsed with water and dried in a stream of nitrogen. 

T. Urbanski, Szyc-Lewanska et al. [18] have recently found that dinitrobenzene-diazo-oxide can be prepared by oxidation of picramic acid with chromium trioxide in the presence of sulphuric acid at 55-60°C. One part of picramic acid is fully oxidized by chromic acid to yield gaseous products CO, C02, N02, NH3 and H20. Nitrogen dioxide acts further as a diazotizing agent on undecomposed picramic acid to yield the diazo compound. The yield of this reaction does not exceed 31% of theoretical calculated on the picramic acid used. 

It appears quite likely that the more complicated explanations referred to may be due to some confusion of less simple side reactions with a simple main reaction.4 Even at temperatures below 60° C., nitrogen dioxide is able to oxidise sulphur dioxide to sulphur trioxide, whilst nitric oxide readily combines with the latter to give the compound 2S08.N0, which is readily decomposed by water giving sulphuric acid and nitric oxide. 

Nitrogen trioxide in atmospheric reactions, 122 rranr-2-butene with, 122 nitrogen pentoxide as source of, 122 oxidation of alkenes by, 122 tetramethyl ethylene (TME) with, 124 Nonequilibrated excited rotamers (NEER), 141 Nonradiative deactivation of Pr and Pfr, 242... 

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