Thorium chloride, anhydrous

Several methods are available for producing thorium metal it can be obtained by reducing thorium oxide with calcium, by electrolysis of anhydrous thorium chloride in a fused mixture of sodium and potassium chlorides, by calcium reduction of thorium tetrachloride mixed with... 

Chlorides. Anhydrous ThCl [10026-08-1] has usually been prepared by direct interaction of thorium metal, hydride, or carbide with chlorine. 

Thorium Molybdate, Th(Mo04)2, is obtained by fusing partly dehydrated thorium chloride with excess of anhydrous sodium molybdate. It pelds tetragonal crystals, with axial ratio... 

Krylov and Chukhlantsev [57KRY/CHU] prepared thorium selenite at 323 K by adding a concentrated solution of selenious acid to a I M solution of thorium chloride. The precipitate was aged for several days in the mother liquor at this temperature, then separated and dried at 373 K. Chemical analysis confirmed the 1 2 ratio between Th and Se(lV) and the specimen was anhydrous. No X-ray diffraction measurements were performed. 

Nearly quantitative yields of acetonitrile can be obtained by passing mixtures of NH3 and acetylene over zircon at 400-500°C [225], over CviOy on Y-alumina at 360°C [226] or by passing mixtures of NH, acetylene and hydrogen at 400-420°C over a mixture of zinc and thorium oxides on silica [227] or at 300-450°C over zinc oxide or zinc sulfate or zinc chloride on silica [228, 229], In such reactions, the role of traces of water has often been questioned. However, acetonitrile could be obtained under rigorously anhydrous conditions, thus demonstrating the direct amination of acetylene with NH,. It was also reported that ethyUdeneimine can be obtained in up to 26% yield [225], However, in the Ught of more recent work [230, 231] the product was most probably 2,4,6-trimethyl-l,3,5-hexahydrotriazine. 

Tellurium hexafluoride, 121 Tetrabromosilane, 38, 40 Tetrapyridino-ferrous chloride, 184 Thiocyanogen solution, 84, 86 standardization, 86 Thionyl bromide, 113 Thorium bromide, ammines, 54 anhydrous, 51... 

Solid [ -l,3bis(trimethylsilyl)cyclopentadienyl]lithium (LiCp", 7.26g, 33.6 mmol, prepared as in Section 33A) is added via an addition tube to a stirred, cooled (0°C) slurry of anhydrous thorium(IV) chloride (Cerac) (6.27 g, 16.8 mmol) in diethyl ether (250 mL). The mixture is stirred at 25 °C for 15 h. Volatile substances are removed at 25 °C and 10 torr. The resultant off-white foam is extracted into warm (50 °C) hexane ( 150mL), and the extract is filtered. The filtrate is concentrated (to 75 mL), then cooled to — 30°C to yield colorless crystals of [ThCp"2Cl2] (1). Yield 4.45 g (40%). A further crop of crystals is obtained from the mother liquor (total yield, 60%). For its characterization, see Table I. 

While the chlorides of strongly electropositive elements such as thorium, lanthanides, and some later 3d metals form adducts with alcohols (57), anhydrous chlorides of boron (6) and silicon (9) form the corresponding alkoxides or alkyl orthoesters, B(OR)3 and Si(OR)4, with primary and secondary alcohols. The reactions of tertiary alcohols are complicated by the facile side formation of tertiary alkyl chloride and water by the reaction between tertiary alcohols... 

Freeman and Smith (32) have prepared the anhydrous chlorides of a number of lanthanides and of thorium by dehydrating the hydrated chlorides with thionyl chloride. Although efforts to obtain anhydrous plutonium trichloride in this way were unsuccessful, it is believed that this may be a useful procedure for actinide elements such as actinium, americium, and curium that have a particularly stable (III) oxidation stage. In general, aqueous methods for preparing tetrachlorides are of little value but anhydrous trichlorides, particularly of the transuranium elements, can be obtained readily from the hydrated trichlorides by dehydration in an atmosphere of hydrogen chloride. 

The related compounds from alkyl substituted cyclooctatetraenes can be best prepared by refluxing bis(alkyl[8Jannulene)thorium(IV) with excess thorium tetrachloride in THF or DME until the yellow color of the thorocene disappears. [8]Annulenethorium(IV) dichlorides can also be prepared by reaction of thorocene with anhydrous hydrogen chloride.23... 

Water. The most common thorium salt, Th(N03)4 5H20, and the chloride are soluble (forming [ThCl2(H20) ] ). Anhydrous Th(S04)2 is soluble in ice water, but it separates as a hydrate on heating. If the solution is allowed to stand without boiling, a series of hydrates will separate, their compositions depending on conditions. This behavior can separate Th qnantitatively at 0°C from the solnble Rth sulfates. 

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