Tetrachloride, oxychloride

Assemble in a fume-cupboard the apparatus shown in Fig. 67(A). Place 15 g. of 3,5-dinitrobenzoic acid and 17 g. of phosphorus pentachloride in the flask C, and heat the mixture in an oil-bath for hours. Then reverse the condenser as shown in Fig. 67(B), but replace the calcium chloride tube by a tube leading to a water-pump, the neck of the reaction-flask C being closed with a rubber stopper. Now distil off the phosphorus oxychloride under reduced pressure by heating the flask C in an oil-bath initially at 25-30, increasing this temperature ultimately to 110°. Then cool the flask, when the crude 3,5-dinitro-benzoyl chloride will solidify to a brown crystalline mass. Yield, 16 g., i.e,y almost theoretical. Recrystallise from caibon tetrachloride. The chloride is obtained as colourless crystals, m.p. 66-68°, Yield, 13 g Further recrystallisation of small quantities can be performed using petrol (b.p. 40-60°). The chloride is stable almost indefinitely if kept in a calcium chloride desiccator. 

Place a mixture of 30 g. of 3 5-dinitrobenzoic acid (Section IV,168 and 33 g. of phosphorus pentachloride in a Claisen flask fit a reflux condenser into the short neck and cork the other neck and side arm (compare Fig. Ill, 31, 1). Heat the mixture in an oil bath at 120-130° for 75 minutes. Allow to cool. Remove the phosphorus oxychloride by distillation under reduced pressure (25°/20 mm.) raise the temperature of the bath to 110°. The residual 3 5-dinitrobenzoyl chloride solidifies on cooling to a brown mass the yield is quantitative. Recrystallise from carbon tetrachloride the yield is 25 g., m.p. 67-68° and this is satisfactory for most purposes. Further recrystallisation from a large volume of light petroleum b.p. 40-60°, gives a perfectly pure product, m.p. 69 -6°. 

The volatile chlorides ate collected and the unreactedsohds and nonvolatile chlorides ate discarded. Titanium tetrachloride is separated from the other chlorides by double distillation (12). Vanadium oxychloride, VOCl, which has a boiling point close to TiCl, is separated by complexing with mineral oil, reducing with H2S to VOCI2, or complexing with copper. The TiCl is finally oxidized at 985°C to Ti02 and the chlorine gas is recycled (8,11) (see also... 

Titanous oxychloride forms yellow tablets, is inert in mineral acids and water and also stable in air. When heated in air, it gives titanium tetrachloride and titanium dioxide. 

Zirconium tetrachloride is instantly hydrolyzed in water to zirconium oxide dichloride octahydrate [13520-92-8]. Zirconium tetrachloride exchanges chlorine for 0x0 bonds in the reaction with hydroxylic ligands, forming alkoxides from alcohols (see Alkoxides, METAl). Zirconium tetrachloride combines with many Lewis bases such as dimethyl sulfoxide, phosphoms oxychloride and amines including ammonia, ethers, and ketones. The zirconium organometalLic compounds ate all derived from zirconium tetrachloride. 

Oxide Chlorides. Zirconium oxide dichloride, ZrOCl2 -8H2 0 [13520-92-8] commonly called zirconium oxychloride, is really a hydroxyl chloride, [Zr4(OH)g T6H2 0]Clg T2H2O (189). Zirconium oxychloride is produced commercially by caustic fusion of zircon, followed by water washing to remove sodium siUcate and to hydrolyze the sodium zirconate the wet filter pulp is dissolved in hot hydrochloric acid, and ZrOCl2 -8H2 O is recovered from the solution by crystallization. An aqueous solution is also produced by the dissolution and hydrolysis of zirconium tetrachloride in water, or by the addition of hydrochloric acid to zirconium carbonate. 

Benzene reacts with carbon tetrachloride ia the presence of anhydrous aluminum chloride to give triphenylchloromethane no tetraphenjlmethane is formed (20). At elevated temperatures, carbon tetrachloride attacks siUca gel forming a siUcon oxychloride (21). 

These formulae explain the scission products of the two alkaloids and the conversion of evodiamine into rutaecarpine, and were accepted by Asahina. A partial synthesis of rutaecarpine was effected by Asahina, Irie and Ohta, who prepared the o-nitrobenzoyl derivative of 3-)3-amino-ethylindole-2-carboxylic acid, and reduced this to the corresponding amine (partial formula I), which on warming with phosphorus oxychloride in carbon tetrachloride solution furnished rutaecarpine. This synthesis was completed in 1928 by the same authors by the preparation of 3-)S-amino-ethylindole-2-carboxylic acid by the action of alcoholic potassium hydroxide on 2-keto-2 3 4 5-tetrahydro-3-carboline. An equally simple synthesis was effected almost simultaneously by Asahina, Manske and Robinson, who condensed methyl anthranilate with 2-keto-2 3 4 5-tetrahydro-3-carboline (for notation, see p. 492) by the use of phosphorus trichloride (see partial formulae II). Ohta has also synthesised rutaecarpine by heating a mixture of 2-keto-2 3 4 5-tetrahydrocarboline with isatoic anhydride at 195° for 20 minutes. 

The above reaction shows that the oxychloride decomposes at the sublimation temperature into the volatile tetrachloride and the nonvolatile oxide. Reduction starts as soon as the chloride vapour contacts the molten magnesium, and this exothermic reaction raises the temperature of the reaction mixture. The temperature of the reduction crucible is maintained in the range of 800 to 875 °C. The process is carefully controlled by matching the sublimation rate of zirconium tetrachloride with the reduction rate. The conclusion of the reduction is indicated by a fall in temperature and pressure. 

In the production of titanium, the chlorination of rutile generates approximately 0.12 tons of waste for every ton of titanium tetrachloride produced. If ilmenite is directly chlorinated, the amount of waste is 1.5 tons for every ton of titanium tetrachloride. Large amounts of ferric chloride are produced along with volatile chlorides and oxychlorides (e.g., aluminum trichloride, silicon tetrachloride, carbon oxychloride, tin tetrachloride, vanadium tetrachloride, vanadium oxychloride) these can be removed by selective distillation. In flu-idized-bed chlorination, the build-up of liquid calcium chloride and magnesium chloride in the fluid bed interferes with the process of fluidization and hence these must be removed. 

SELENIUM TETRACHLORIDE SELENIUM HEXAFLUORIDE SELENIUM OXYCHLORIDE SELENIUM DIOXIDE SILICON... 

Combination with bipyridyl hgand in carbon tetrachloride followed by hydrolysis yields a molybdenum oxychloride bipyridyl complex of formula MoOCR(bipy). When mixed with ammonium chloride in acetonitrile and water, an oxychloride-acetonitrile complex, NIRfMoOCRCHsCN], is obtained. 

Selenium oxychloride may be prepared by several methods (1) by passing chlorine gas into a suspension of selenium dioxide in carbon tetrachloride, (2) by heating thionyl chloride, SOCE, with selenium dioxide, (3) by dehydration of dichloroselenious acid, H2Se(CE)02, and (4) by fusion of selenium dioxide, selenium, and calcium chloride. 

Zirconium tetrachloride decomposes in water forming zirconium oxychloride and hydrochloric acid ... 

Pyrosulphuryl Chloride, S205C12.—Rose first prepared this substance in 1838 by the interaction of sulphur trioxide and sulphur monochloride.4 It is formed by the action of many chlorides on sulphur trioxide sulphur monochloride,4 thionyl chloride,5 silicon tetrachloride,6 phosphorus pentachloride,7 phosphorus oxychloride,8 sodium chloride 9 and carbon tetrachloride 10 all yield the desired product when treated with sulphur trioxide at a suitable temperature. With sodium chloride a mixture of pyrosulphufyl chloride and sodium pyrosulphate is obtained, whilst with the exception of carbon tetrachloride and phosphorus pentachloride, which are converted into oxychlorides, all the remaining chlorides are changed into oxides ... 

By various methods from selenium dioxide for example, by the action of hydrogen chloride, thionyl chloride or phosphorus pentachloride. The last-named is perhaps the most convenient chlorinating agent. A mixture of the pentachloride and the dioxide is heated until chemical change causes it to solidify. Phosphorus oxychloride can be distilled off with the aid of a current of carbon dioxide and the residual selenium tetrachloride purified by sublimation.8... 

The tetrachloride may be purified by recrystallisation from phosphorus oxychloride, from which it separates as cubical crystals. It is practically insoluble in carbon disulphide, which can therefore be used to remove any monochloride present. The heat of formation of the tetrachloride from chlorine and amorphous selenium is 46-1 Calorics 4... 

By adding the calculated amount of dry selenium dioxide to selenium tetrachloride suspended in carbon tetrachloride. The oxychloride formed in the cold dissolves in the carbon tetrachloride, from which it may be obtained by distillation. Carbon tetrachloride distils at 76° to 77° C., while the selenium oxychloride distils over at 176-4° C.1... 

When a mixture of selenium dioxide and selenium tetrachloride is heated in a sealed tube, selenium oxychloride is formed 5... 

Selenium oxychloride absorbs all light up to a wave-length of 4050pp. It is miscible with chloroform, carbon disulphide and benzene without chemical change. It is also soluble in carbon tetrachloride, but after a time reaction takes place with formation of selenium tetrachloride and carbonyl chloride.10 At the ordinary temperatures selenium oxychloride is not miscible with the paraffin hydrocarbons,... 

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