Organic volatile halides

For all research carried out with commercial ionic liquids we recommend a serious quality check of the product prior to work. As already mentioned, a good commercial ionic liquid may be colored and may contain some traces of water. However, it should be free of organic volatiles, halides (if not an halide ionic liquid), and all ionic impurities. 

The description of the electroreductive treatments of organic halides is subdivided into the following sections organic volatile halides, CFCs, polyhaloacetic acids, polyhalophenols, polychlorohydrocarbons and other compounds. These sections are meant to complete the discussion and information, provided in the preceding parts, by focussing on each specific category of compounds and their related working examples. 

Catalyst-poisoning studies have concentrated on the potential poisons introduced with fuel, particularly on lead, which has been added intentionally to improve the combustion characteristics at the high compression ratios employed in modem internal combustion engines prior to the introduction of exhaust purification catalysts. The lead is usually introduced as motor mix which contains tetraethyllead in a mixture with organic halides, chlorides or bromides. These halides transport the lead in the form of volatile halides out of the engine and into the exhaust, and are hence termed lead scavengers. Thus the potential catalyst-poison elements associated with the additive mixture are Pb, Br, and Cl. 

Other routes include the high-temperature halogenation of metal oxides, sometimes in the presence of carbon, to assist removal of oxygen the source of halogen can be X2, a volatile metal halide CX4 or another organic halide. A few examples of the many reactions that have been used industrially or for laboratory scale preparations are ... 

CVD Reactions. The rhodium halides, like those of the other platinum group metal s, are volatile with a decomposition pointtoo close to the vaporization point to make them usable for CVD transport. The metal is commonly produced by the decomposition of metallo-organic precur-... 

In comparison to the two other described educt compounds 4a and 18, the anions of 31a and 31b can also be prepared in a one step synthesis in satisfying yields, without the application of high pressure conditions starting from 3a or 19a. This compound should open intensive exploration of Tc(I) and Re(I) chemistry. In contrast to the other two educts, no competing ligands are present. The halides bind only very weakly and the carbonyls are easily withdrawn from equilibrium by volatility. As shown in the previous section, a number of examples illustrate the versatility of this educt. It can be applied not only for substitutions in organic solvents but also in water, and therefore allows reactions with ligands that are... 

Vinyl Chloride under Unsaturated Alkyl Halides Volatile Organic Compounds... 

Treatment of polymer films by reactive gases or reactive volatil compounds allows to easily modify polymers containing alcohols, hydroperoxides, carboxylic acids (or acids halides), double bonds or piperidine groups. New functional groups as organic nitrites, nitrates, iodides, acid halides (Cl, F), amides, esters, peresters and nitroxyl radicals can be generated by a single reaction or by combination of two consecutive treatments. The reactions are very efficient on thin films (ca 50-100 pm) and can be controlled by transmission and reflexion 1R spectroscopy. 

All metallic chlorides, except silver chloride and mercurous chloride, are soluble in H.O. but lead chloride, cuprous chloride and thallium chloride are only slightly soluble. Metallic chlorides when heated melt, and volaiilize or decompose, e.g.. sodium chloride, mp 804 (2 calcium, strontium, barium chloride volatilize at red heal magnesium chloride crystals yield magnesium oxide residue and hydrogen chloride cupric chloride yields cuprous chloride and chlorine. Sec also Chlorine Chlorinated Organics. Halides Hypochlorites and Sodium Chloride. 

GC has been used extensively for the separation and determination of volatile organic molecules, and most aspects of this application area are fully documented in monographs on this technique. In the inorganic trace analysis area, however, fewer species possess the required volatility, and applications tend to be limited to the separation of volatile species of low molecular weight (such as methyl derivatives of As, Se, Sn, Hg) and the separation of semi-volatile organo-metals, metal halides, metal hydrides, metal carbonyls and metal chelates. For organo-metal species, the type of detection system required varies with the nature of the analyte, and the options include electron capture detection, flame photometric detection (sometimes ICP), AAS and MS. 

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