Nickel solvent action

The solvent action of nickel is shown in Fig. 12.2. When a nickel-graphite mixture is held at the temperature and pressure found in the cross-hatched area, the transformation graphite-diamond will occur. The calculated nickel-carbon phase diagram at 65 kbar is shown in Fig. 12.3. Other elemental solvents are iron and cobalt.i i However, the most common... 

Although not so generally applicable for the preparation of dicyclopentadienyl metal compounds as the sodium cyclopenta-dienide method, the amine procedure represents the simplest preparation of ferrocene. The amine procedure can also be employed for dicyclopentadienylnickel (about 80% yield), using nickel bromide obtained by the action of bromine on nickel metal powder and 1,2-dimethoxyethane as the solvent. The method of preparation given here is a modified version of that originally described. ... 

The action of n-butyllithium in THF at low temperature leads to the anion. After reaction with an electrophilic compound, e hydrolysis can generally be carried out in polar solvents (acetone, alcohols, acetonitrile) in the presence of mercury(II) chloride or oxide and water.In other cases, NBS, - chloramine T, cerium(IV) ammonium nitrate, n-tributyltin hydride, trialkyloxonium tetrafluorobor-ate, thallium nitrate or photochemistry can be used. Desulfurization by Raney nickel gives hydro-carbons. ... 

In its ground form it is then subjected to the action of a solvent such as caustic soda, or the like, which will dissolve all of the alloyed material with the exception of the nickel. After this treatment the subnatent fluid is decanted and the residue, consisting of finely divided nickel thoroughly washed. 

The description of crystal type and color of several metallic hydrazine nitrates are summarized in Table 13.8. The density of NHN is 2.07 g cm . Nickel and cobalt hydrazine nitrate are practically insoluble in common organic solvents (e.g., ethanol, acetone) and sparingly soluble in water (0.47 g 1 at 30 °C, 2.31 g 1 at 70 °C). NHN bums upon the action of 96 % sulfiuic acid, but weak acid makes it decompose more gently CoHN explodes in contact with concentrated sulfuric acid. NHN mildly reacts with a 10 % solution of sodium hydroxide and this can be used for producing a chemical decomposition. NHN is stable on exposure to sunlight and it hardly reacts at aU with common metals. Cobalt hydrazine nitrate is unstable and decomposes slowly, even in the presence of traces of moisture, changing in color from brown to greenish [16, 17]. 

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