Titanium chloride, naming

The use of a Lewis acid (e.g., friethylfluoroborate, zinc chloride, stannous chloride, titanium chloride, iron(m)chloride) and other reagents (e.g., iodine, trimethylsilane, trifluoiomethane-sulfonylsilane) have also been recommended. Exhaustive lists of catalysts and conditions can be found in reviews devoted to carbohydrates [5-7], or to general organic chemistry [27,28], However, one can add the new catalyst, which has been introduced for the smooth formation of p-methoxybenzylidene acetals and p-methaxy-phenylmethyl methyl ether [29], namely 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), and has been applied very recently [30] to the synthesis of isopropylidene mixed acetals. 

As a catalyst for the ring condensation Lewis acids such as for instance zinc chloride, zinc bromide, boron trifluoride, ferric chloride, stannic chloride, titanium chloride or iodine are used, zinc chloride and zinc bromide having proved to be more particularly suitable. Water binding substances such as neutral substances as for instance magnesium sulfate, sodium sulfate, calcium sulfate or molecular sieves may be used, the last-named having proved more particularly suitable. 

To prepare the a anomer (60) of the aminonucleoside [ namely, 9-(3-amino-3-deoxy-)8-D-ribofuranosyl)-iV , lV -dimethyladenine], 9-(3-ac-etamido-3-deoxy-a-D-arabinofuranosyl) -JV , iV -dimethyl-2- (methylthio) -adenine (59) was prepared by condensation of the titanium chloride complex of 3-acetamido-l-0-acetyl-2,5-di-0-benzoyl-3-deoxy-arabinofuranose with iV ,iV -dimethyl-2-(methylthio)adenine, followed by desulfurization and de-O-acylation. The inversion of the hydroxyl group on C-2 by way of its methylsulfonyl ester then gave the desired a anomer (60) of the aminonucleoside, isolated as its vanillylidene derivative. " The A-acetyl... 

Another chloride reduction process, originally developed by Hunter for titanium tetrachloride and known by his name, uses sodium as the reductant. In this process liquid sodium and titanium tetrachloride are simultaneously metered into a steel retort under an argon atmosphere. The highly exothermic reduction reaction... 

In order to understand the general behavior of the tested materials, scoping tests were conducted in 25 mg/L gold(III)-chloride solutions at 25°C and 80°C with different initial pH values, namely 1.5, 4 and 8. After the start of the experiment the pH was not further adjusted, i.e., it could change freely. It remained similar to the initial pH in all cases. From these tests it was found that, in the case of the iron-oxide based adsorbents, dissolution of the solid took place at pHaluminum oxides and titanium oxide was observed at this pH. At pH>2 all adsorbents were found to be stable and did not dissolve during the experiment. 

Fig. 17.42. Reduction of epoxides with electron-transferring agents and 1,4-cyclohexadiene as the H atom donor. The more sterically hindered C-0 bond cleaves in a regioselective fashion, namely the Csec-0- instead of the Cprim-0 bond in the upper example—stoichiometric amounts of bis(cyclopentadienyl)titanium(III) chloride (CpJiCl) act as electron carrier—or the Ctert-0- instead of the C rin -0 bond in the bottom example, respectively (electron carrier catalytic amounts of Cp2TiCl/stoichiometric amounts of manganese powder).

There are two major processes for the manufacture of titanium dioxide pigments, namely (1) sulfate route and (2) chloride route. In the sulfate process, the ore limonite, Fe0Ti02, is dissolved in sulfuric acid and the resultant solution is hydrolyzed by boiling to produce a hydrated oxide, while the iron remains in solution. The precipitated titanium hydrate is washed and leached free of soluble impurities. Controlled calcinations at about 1000°C produce pigmentary titanium dioxide of the correct crystal size distribution this material is then subjected to a finishing coating treatment and milling. The process flow sheet is shown in Fig. 7.1 [4],... 

Various substituted benzimidazoles have been synthesized in very good yields in solvent-free conditions from 1,2-diaminobenzene and aldehydes in the presence of titanium(IV) chloride as a catalyst. The method is applicable to most aromatic, unsaturated and aliphatic aldehydes and to substituted 1,2-diaminobenzenes without significant differences [14]. Several other catalysts, namely iodine [15], hydrogen peroxide [16], zirconyl(IV) chloride [17], boron trifluoride diethyl etherate [18], ytterbium perfluorooctane sulfonates [19,20], zeolite [11,21], and L-proline [22], have been effectively used for the synthesis of benzimidazole derivatives. 

Name three other volatile chlorides that can appropriately be made by the method used here for titanium tetrachloride. 

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