Azide, oxidation

Mercury Acetylenic compounds, chlorine, fulminic acid, ammonia, ethylene oxide, metals, methyl azide, oxidants, tetracarbonylnickel... 

Triazenes can be prepared by the following three methods (Scheme 1) (1) redox reactions (reduction of azides, oxidation of triazanes), (2) building or splitting of nitrogen chains, and (3) exchange of substituents (mutual transformation of triazenes). 

Examples of the former take place when radical 234 is stabilized by a heteroatom. When Y is an alkoxy moiety, an oxonium is formed and trapped by several external nucleophiles [193]. When an amide was present on the starting material, as was the case with 235, amino sugars were obtained in good yields (68% for 238) [ 194]. Finally, when Y is an azide, oxidation to the a-azido cation delivers nitriles upon loss of nitrogen [195]. 

In addition to the barrierless discharge of hydrogen ions, there are also other electrode reactions which follow the regularities of barrierless processes. Above all, these include the anodic evolution of chlorine at electrodes made of different materials and the azide oxidation reaction. These processes will be considered in greater detail in Chapter 5. 

The complex reaction of azide oxidation has not been investigated as thoroughly as the chlorine evolution process. However, on the basis of the above data, we can conclude that the most probable mechanism is a slow quasibarrierless reaction, while for higher potentials, it is an ordinary reaction like electrochemical desorption. 

It was mentioned above that similar kinetic regularities were observed during azide oxidation at other anodes made of metals from the platinum group or the iron group. Although this question was not specially investigated, it seems probable that for these metals also, the rate of the process is determined by the stage of quasibarrierless electrochemical desorption. 

The azides are salts which resemble the chlorides in solubility behaviour, for example silver azide, AgNj, is insoluble and sodium azide, NaN3, soluble in water. Sodium azide is prepared by passing dinitrogen oxide over molten sodamide ... 

Heavy water, see Hydrogen[ H] oxide Heazlewoodite, see rn-Nickel disulfide Hematite, see Iron(III) oxide Hermannite, see Manganese silicate Hessite, see Silver telluride Hieratite, see Potassium hexafluorosilicate Hydroazoic acid, see Hydrogen azide Hydrophilite, see Calcium chloride Hydrosulfite, see Sodium dithionate(III)... 

Copper Acetylene and alkynes, ammonium nitrate, azides, bromates, chlorates, iodates, chlorine, ethylene oxide, fluorine, peroxides, hydrogen sulflde, hydrazinium nitrate... 

Iodine Acetaldehyde, acetylene, aluminum, ammonia (aqueous or anhydrous), antimony, bromine pentafluoride, carbides, cesium oxide, chlorine, ethanol, fluorine, formamide, lithium, magnesium, phosphorus, pyridine, silver azide, sulfur trioxide... 

Lead Ammonium nitrate, chlorine trifluoride, hydrogen peroxide, sodium azide and carbide, zirconium, oxidants... 

Manganese dioxide Aluminum, hydrogen sulfide, oxidants, potassium azide, hydrogen peroxide, peroxosulfuric acid, sodium peroxide... 

Dipolar cycloaddition reactions with azides, imines, and nitrile oxides afford synthetic routes to nitrogen-containing heterocycles (25—30). 

The air bag industry has become one of the principal users of pyrotechnic compositions in the world. Most of the current air bag systems are based on the thermal decomposition of sodium azide, NaN, to rapidly generate a large volume of nitrogen gas, N2. Air bag systems must function immediately (within 50 ms) upon impact, and must quickly deploy a pulse of reasonably cool, nontoxic, unreactive gas to inflate the protective cushion for the driver or passenger. These formulations incorporate an oxidizer such as iron oxide to convert the atomic sodium that initially forms into sodium oxide, Na20. Equation 1 represents the reaction. 

Boron mixed with an oxidizer is used as a pyrotechnic. This ordnance appHcation for missiles and rockets is predominandy military. However, boron is also used in air bags, placed in automobiles as safety devices, for initiating the sodium azide [26628-22-8] which fiHs the bag with nitrogen (13). Other boron compounds are also used in the air-bag pyrotechnic appHcation. 

Ammonia, hydrazine, nitrites, and azides ate oxidized by bromine. Nitrogen is often a product of such reactions. 

When chloro compounds are treated with sodium azide in ethanol or aqueous acetone the corresponding azides or tetrazolo[l,5-6]pyridazines are obtained. For example, 3-azido-and 4-azido-pyridazine 1-oxides are obtained from the corresponding chloro compounds ... 

Perhaps one of the most exciting developments in the chemistry of quinoxalines and phenazines in recent years originates from the American University of Beirut in Lebanon, where Haddadin and Issidorides first made the observation that benzofuroxans undergo reaction with a variety of alkenic substrates to produce quinoxaline di-AT-oxides in a one-pot reaction which has subsequently become known as the Beirut reaction . Many new reactions tend to fall by the wayside by virtue of the fact that they are experimentally complex or require starting materials which are inaccessible however, in this instance the experimental conditions are straightforward and the starting benzofuroxans are conveniently prepared by hypochlorite oxidation of the corresponding o-nitroanilines or by pyrolysis of o-nitrophenyl azides. 

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