Electrical aluminium compounds

M.p. 296 C. Accepts an electron from suitable donors forming a radical anion. Used for colorimetric determination of free radical precursors, replacement of Mn02 in aluminium solid electrolytic capacitors, construction of heat-sensitive resistors and ion-specific electrodes and for inducing radical polymerizations. The charge transfer complexes it forms with certain donors behave electrically like metals with anisotropic conductivity. Like tetracyanoethylene it belongs to a class of compounds called rr-acids. tetracyclines An important group of antibiotics isolated from Streptomyces spp., having structures based on a naphthacene skeleton. Tetracycline, the parent compound, has the structure ... 

Electrical Conductivity. A further topic which needs to be considered is the correlation found by Zlamal, Ambroz, and Vesely [2] between the specific conductivity of solutions (mainly in ethyl chloride) of aluminium chloride containing various quantities of a polar compound (acetonitrile, butyraldehyde, ethanol, etc.) and the DP of the polyisobutenes formed in these solutions. Over a certain range of concentrations there is an inverse correlation between the specific conductivity, which has a sharp minimum when the ratio [AlCl3]/[Additive] = 1, and the DP, which at the same composition shows a sharp maximum. 

The electrical conductivity in the liquid state of the halides, e.g. the chlorides, also provides a well-marked difference between the non-conducting shielded compounds and the good conducting non-shielded compounds with free ions in the melt (Biltz, Klemm)17 . Aluminium chloride here also forms a special case in so far that quite exceptionally the solid substance (coordination lattice) has a higher conductivity than the liquid (molecules A12C16). 

A commercial synthesis of 2,6-diphenylphenol is reported by Hay at General Electric, USA811. First, cyclohexanone was condensed with 50% sodium hydroxide at 150-190 °C giving the 2-mono- and the 2,6-disubstituted cyclohexanone derivatives. In the second step, after removal of water and sodium hydroxide, these are dehydrogenated at 300-350 °C with a palladium aluminium oxide catalyst for 20 minutes (e.g. 45 % total yield of 2,6-diphenyl-phenol). It is a useful compound in technical production and has been studied by Hay and coworkers 82) (see also 83,84)). Polymeric diphenylphenol ethers ( Tenas ) 85) or copolymers with polystyrene ( Normyl ) have been produced on a large scale by General Electric e.g. as thermoplasts 86). 

Methane from Carbides.—Another method of preparation is of interest and importance because of its connection with theories as to the formation of methane and other hydrocarbons in petroleum. With some metals carbon forms compounds which are very stable at high temperatures, and which have been artificially produced in the electric furnace (about 35O0°C.) by Moissan. These metallic carbon compounds, known as carbides, are, most of them, easily decomposed by water at ordinary temperatures, and when so decomposed they yield various members of the hydrocarbon group of compounds. A familiar example of this class of reactions is the one by which acetylene gas is made by the action of water on calcium carbide. The carbide of aluminium decomposes with water and yields methane according to the foUowing reaction ... 

Aluminium ions produce an electric field in aqueous solution, which is sufficient for hydrated hydroxyions to form and polymerization to occur. Polymerization of the hydrolysis product results in new compounds, which structure has not yet been found [1,2,3,4]. 

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