Sulphur, Selenium, and Tellurium Compounds

Sulphur, Selenium, and Tellurium Compounds.—The crystal structure of the metal-rich zirconium sulphide Zr Sj has been determined and each sulphur atom shown to be at the centre of a square antiprism of zirconium atoms. The reaction of ZrS2 with potassium in liquid ammonia has been shown to give four K ZrS2 phases (.x = 1, 0.86, 0.71, or 0.71—0.22) which differ in the nature of the co-ordination sites occupied by the potassium atoms between the ZrS2 layers. ZrCl reacts with NaS2P(OEt)2 in toluene to form [Zr S2P-(OEt)2 4], which appears to involve a trigonal-dodecahedral arrangement of sulphur atoms about the metal.  

The non-stoicheiometric zirconium silicoselenide, Zr2.00Si1.90Se1.99 has been studied crystallographically. The phase ZrjTe has been characterized in the zirconium-rich region of the zirconium-tellurium system and the phases 

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The chemistry of organosilicon-sulphur compounds has been reviewed periodically since I9601. Comprehensive Organometallic Chemistry (published 1982) provides the most extensive up-to-date summary of the field of organosilicon chemistry, including sections on sulphur, selenium and tellurium compounds and their use in organic synthesis, which is also mentioned in Comprehensive Organic Chemistry (published 1979)2. 

Preparation of Sulphides, Selenides, and Tellurides using the Elements Themselves, or Other Inorganic Sulphur, Selenium, and Tellurium Compounds.—Symmetrical sulphides can be obtained in 12—66% yields from an alkyl chloride, sulphur, and NaOH in DMSO. The same system with a bePxZyl cyanide R PhCHCN produces the unsymmetrical sulphides R PhC(CN)SR with an alkyl halide some... 

Miscellaneous Methods of Preparation.— This Chapter is interwoven with accounts of the reactions of sulphur, selenium, and tellurium compounds which amount to the conversion of one sulphur-containing functional group into another. This small section is included to collect together a variety of methods for the synthesis of sulphides from sulphur compounds other than those mentioned in the preceding sections. 

Sulphuranes and Hypervalent Sulphur, Selenium, and Tellurium Compounds... 

D. H. Reid, ed., Organic Compounds of Sulphur. Selenium, and Tellurium, Spec. Period. Rep. Chem. Soc., London. 

R. J. S. Beer, "Organic Compounds of Sulphur, Selenium and Tellurium (Sr. Reporter,... 

Sulphur, selenium and tellurium exhibit allotropy, and in certain of their crystalline forms the elements are isomorphous. As would be expected from the increased positive character of tellurium, the allotropy of this element is less well defined. In the liquid condition the elements arc miscible with one another and yield mixed crystals the ternary system, S— Sc—Tc, exhibits neither the formation of compounds nor ternary eutectics, but contains two zones of complete miscibility in which there exist mixed crystals of selenium and tellurium with sulphur, and of sulphur and tellurium with selenium.2... 

Saturated Cyclic Compounds of Sulfur and Selenium , A. Fava and E. Sandri, in Organic Compounds of Sulphur, Selenium and Tellurium , ed. D. R. Hogg, Royal Society of Chemistry, LoridOh, 1979, vol. 5, pp. 213-246. 

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