Oxidizing agents nickel compounds

A promising new battery now under development employs unusual iron(VI) compounds at the anode. Because iron(VI) is such a strong oxidizing agent, its compounds are normally very unstable, but these problems seem to have been solved by removing contaminants such as cobalt and nickel. These so-called super-iron batteries reportedly can furnish 50% more energy than conventional dry cell batteries. 

Fluorine is the most reactive of all elements, in part because of the weakness of the F—F bond (B.E. F—F = 153 kj/mol), but mostly because it is such a powerful oxidizing agent (E ed = +2.889 V). Fluorine combines with every element in the periodic table except He and Ne. With a few metals, it forms a surface film of metal fluoride, which adheres tightly enough to prevent further reaction. This is the case with nickel, where the product is NiF2. Fluorine gas is ordinarily stored in containers made of a nickel alloy, such as stainless steel (Fe, Cr, Ni) or Monel (Ni, Cu). Fluorine also reacts with many compounds including water, which is oxidized to a mixture of 02> 03> H202, and OF2. 

In most of its compounds nickel has a +2 oxidation number, but it is possible to get a higher state by heating Ni(OH)2 with hypochlorite ion in basic solution. Hypochlorite ion, CIO-, is one of the stronger oxidizing agents at our disposal in basic solution. There is considerable argument about the formula of the black solid that is formed, but we shall label it as Ni208 and write the equation... 

Ethylene (tert-phosphine) complexes of zero-valent nickeP and platinum have been known for years. Analogous palladium complexes can be synthesized along the same lines as those reported for the nickel compounds, using ethoxy-diethylaluminum(III) as the reducing agent in the presence of ethylene. These palladium-ethylene complexes may serve as starting materials for oxidative addition reactions, since the ethylene ligand is loosely bonded. ... 

Benzoyl peroxide (dibenzoyl peroxide), (CjHjCOO>2 (mp 104-106 °C dec), and /r-nitrobenzoyl peroxide (p-02NCgH4COO)2 (mp 156 °C dec), which is synthesized from p-nitrobenzoyl chloride and sodium peroxide [229], are rarely used as oxidants, and if so, they do not offer appreciable advantages over other organic oxidation agents. The anti addition of benzoyl groups to double bonds and the benzoxylation of aromatic rings are achieved in the presence of iodine [230], and alcohols are oxidized to carbonyl compounds in the presence of nickel dibromide [231],... 

Various methods, such as thermolysis, photolysis, interaction with triva-lent phosphorus compounds [e.g., PR3, P(NR2)3, P(OR)3] or bases, and reaction with nickel catalysts or oxidizing agents (e.g., H2O2, RCO3H), are useful for the ring-contraction reaction of heterocycles by sulfur extrusion. In a number of cases, the reagent adds to the sulfur atom in a first reaction step (Scheme 4). Hence, instead of elemental sulfur, its derivatives are eliminated in the subsequent ring contraction, such as SO2 in the presence... 

The first step in the GC determination of carbon and hydrogen is quantitative oxidation of the sample organic compounds, usually with a catalyst. Copper oxide is commonly used, but the reaction is relatively slow and elevated temperatures of about 900°C are required. With silver permanganate the reaction temperature is reduced to 550°C [34, 35] and with cobalt oxide to 750°C [36, 37] both compounds provide a shorter oxidation time. Other catalytic oxidizing agents, such as nickel oxide [38, 39] and cerium(IV) oxide [40], have been found promising. Platinum can also be used, especially when it is necessary to avoid the retention of any oxidation products by the solid catalyst. 

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