Titanium chloride-Potassium

Solutions of low-valence titanium chloride (titanium dichloride) are prepared in situ by reduction of solutions of titanium trichloride in tetrahydrofuran or 1,2-dimethoxyethane with lithium aluminum hydride [204, 205], with lithium or potassium [206], with magnesium [207, 208] or with a zinc-copper couple [209,210]. Such solutions effect hydrogenolysis of halogens [208], deoxygenation of epoxides [204] and reduction of aldehydes and ketones to alkenes [205,... 

Aluminum chloride Potassium t-butoxide Hydrogen bromide Thionyl chloride Titanium tetrachloride Hydrogen chloride... 

Standardization of the Titanium Chloride Solution Drain any standing titanium chloride (TiCl3) from the feed lines and buret, and refill with fresh solution. Add 3.0 g of Ferrous Ammonium Sulfate to a wide-mouth Erlenmeyer flask followed by 200 mL of water, 25 mL of 50% sulfuric acid, 25 mL of 0.1 N Potassium Dichromate Solution (by pipet), and 2 or 3 boiling chips. Boil the solution vigorously on a hot plate for 30 s to remove dissolved air, then quickly transfer the flask to the titration apparatus, securely connect the stopper assembly, and start the carbon dioxide flow and stirrer. Pass carbon dioxide over the solution for 1 min before beginning the titration. 

Titanium tetrachloride is used as an intermediate in the production of titanium metal, titanium dioxide, and titanium chloride pigments, as a polymerization catalyst, in the manufacture of iridescent glass and faux pearls, and with ammonia to produce smoke screens. It is also used as a catalyst in many organic syntheses in the chemical industry. Titanium tetrachloride was formerly used with potassium bitartrate as a mordant in the textile industry, and with dye-woods in dyeing leather. 

Macro quantities of selenium can be determined gravimetrically after reduction to the elemental form by various reagents such as tin (II) chloride, potassium iodide, or ascorbic acid (I). Ooba described a technique whereby the element is precipitated from perchloric acid solution with hydrazine (2). Selenium may be titrated with standard solutions of sodium thiosulfate, iodide, and ferrous, chromous, or trivalent titanium salts after oxidation to Se(VI) (I). Photometric and fluorometric methods based on formation of the piaselenol with diaminobenzidine or 2,3-diaminonaphthalene has been used for the determination of selenium (I, 3,4,5). Interfering elements such as As, Co, Cr, Cu, Fe, Hg, and Ni, are masked with EDTA or other chelating agents. 

Samarium selenides. Reductive cleavage of ArSeSeAr by samarium is catalyzed by a great number of metal halides bismuth(III) chloride, cadmium chloride, chromium(IIl) chloride, cobalt(II) chloride, potassium iodide, and titanium(lV) chloride. The resulting samarium arylselenides readily react with various organic halides. 

A combination of alkali metal salts, particularly potassium chloride, with low-valent titanium reagents generated from titanium chlorides with lithium or magnesium in either THF or DME are effective reagents for stereoselective McMurry coupling reactions of aldehydes and ketones to substituted alkenes (Figure 1.11). 

Electrolysis of an alkali fluoride melt containing titanium trichloride or dichloride is regarded as the most satisfactory process. A lithium chloride, potassium chloride eutectic, containing 60 mol % of the former, has a melting-point of only 350°C and allows electrolysis to be carried out satisfactorily at 550°C. The more conventional sodium chloride, potassium chloride eutectic is cheaper, but has a melting-point of 650°C. 

Popov. B. N., Kimble, M. C., White, R. E. and Wendt, H. (1991) Electrochemical behaviour of titanium(II) and titaniun(III) compounds in molten lithium chloride/potassium chloride eutectic melts, J. Appl. Electrochem. 21, 351-357. 

Volkov. S. V., Shapoval, V. I., Buryak, N. I. and Lutsenko, V. G. (1980) Electronic spectra of titanium(III) complexes in sodium chloride-potassium chloride and sodium chloride-potassium chloride-potassium fluoride melts, Zhur. Neorg. Khim. 25 2993-2997 [Russ. J. Inorg. Chem. 25 1645-1648],... 

Density of potassium-boron-titanium chloride-fluoride melts 92... 

Several methods have been proposed based on the decomposition of diazonium salts. The volume of nitrogen can be measured after treating aryldiazonium compounds with copper(i) chloride , potassium iodide , or titanium(iii) chloride . Otherwise, the excess catalyst can be determined, as in the case of titanium(m) chloride , or chromium(ii) chloride . The diazonium compound strongly heated with hydriodic acid yields iodine which can be titrated . 

When titanium dissolves in dilute hydrochloric acid, a violet solution containing titanium(III) ions is formed. This solution rapidly decolorises acidified aqueous potassium permanganate at room temperature. Titanium(IV) chloride is a colourless covalent liquid completely hydrolysed by water. Titanium(III) chloride forms hydrated titanium(III) ions in water and disproportionates when heated in a vacuum. 

Preparation and Manufacture. Magnesium chloride can be produced in large quantities from (/) camalhte or the end brines of the potash industry (see Potassium compounds) (2) magnesium hydroxide precipitated from seawater (7) by chlorination of magnesium oxide from various sources in the presence of carbon or carbonaceous materials and (4) as a by-product in the manufacture of titanium (see Titaniumand titanium alloys). 

The Stock Oxidation-Number System. Stock sought to correct many nomenclature difficulties by introducing Roman numerals in parentheses to indicate the state(s) of oxidation, eg, titanium(II) chloride for TiCl2, iron(II) oxide for FeO, titanium(III) chloride for TiCl, iron(III) oxide for Fe203, titanium(IV) chloride for TiCl, and iron(II,III) oxide for Fe O. In this system, only the termination -ate is used for anions, followed by Roman numerals in parentheses. Examples are potassium manganate(IV) for K2Mn02, potassium tetrachloroplatinate(II) for K PtCl, and sodium hexacyanoferrate(III) for Na3Fe(CN)3. Thus a set of prefixes and terminations becomes uimecessary. 

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