Tellurium compounds synthesis

Krief, A. In The Chemistry of Organic Selenium and Tellurium Compounds. Synthesis of Selenium and Tellurium Ylides and Carbanions Application to Organic Synthesis Patai, S., Ed. Wiley, 1987 Vol 2, chap 17, p 684. 

P. Laur, Chiral Selenium and Tellurium Compounds Synthesis and Properties, in Proc. Int. Symp. Org. 

P. Laur, Chiral Selenium and Tellurium Compounds Synthesis and Properties, in Proc. Int. Symp. Org. Selenium Tellurium Compd., 3rd, 1979 (pub. 1981), p. 219 (229). 

Shimizu, T Kamigata, N. Optically Active Selenium and Tellurium Compounds. Synthesis and Application for Asymmetric Synthesis. A Review, Org. Prep. Proc. Ira. 1997, 29, 605-629. 

In this chapter, recent development on the synthesis and stereochemistry of optically active chalcogen compounds over the last 10 years will be described, focusing mainly on chiral selenium and tellurium compounds. 

For books, see (a) C. Paulmier, Selenium Reagents and Intermediates in Organic Synthesis, Pergamon Press, Oxford, 1986 (b) S. Patai and Z. Rappoport (eds), The Chemistry of Organic Selenium and Tellurium Compounds, vol 2, Wiley, New York, 1987. 

Diaryltellurium oxides 8 and aryltellurinic acid anhydrides 9 are white solids and find use as mild oxidizing agents in organic synthesis. These classes of organic tellurium compounds are quite stable and can be handled with no need for special care. 

A promising method for the synthesis of unsymmctrical diorgano tellurium compounds uses carboxylic acid derivatives and diaryl ditellurium as starting materials. The carboxylic acid chloride, prepared in quantitative yield from the acid and oxalyl chloride is added slowly to a mixture of a diary] ditellurium and the sodium salt of 2-mercaptopyridine N-oxide in toluene at 35°. Under normal laboratory light the aryl tellurium radicals... 

When primary alkyl phenyl tellurium or secondary alkyl phenyl tellurium compounds in methanol were treated with an excess of 3-chloroperoxybenzoic acid at 20, the phenyltelluro group was eliminated and replaced by a methoxy group. This reaction, which converts alkyl halides used in the synthesis of alkyl phenyl telluriums to alkyl methyl ethers, produced the ethers in yields as high as 90%3-4 Olefins are by-products in these reactions4 With ethanol as the solvent, ethyl ethers were formed. Other oxidizing agents (hydrogen peroxide, ozone, (ert.-butyl hydroperoxide, sodium periodate) did not produce alkyl methyl ethers. 

For reviews see (a) Paulmier C (1986) In Selenium reagents and intermediates in organic synthesis. Pergamon, Oxford (b) Patai S (ed) (1987) In The chemistry of organic selenium and tellurium compounds. Wiley, New York (c) Back TG (ed) (1999) In Organoselenium chemistry a practical approach. Oxford University Press, Oxford (d) Nishibayashi Y, Uemura S (1996) Rev Heteroatom Chem 14 83 (e) Uemura S (1998) Phosphorus Sulphur and Silicon 136/138 219 (f) Wirth T (1999) Tetrahedron 35 1... 

An earlier report claiming the synthesis of tetrakis[organothio] tellurium compounds from tellurium tetrachloride and thiols in cold ethanol was found to be incorrect. These reactions produced equimolar mixtures of bis[organothio] tellurium compounds and diorgano disulfanes. These mixtures were not purified and, therefore, gave C, H, S, and Te percentages expected for the tetrakis[organothio] tellurium. ... 

Azobenzene or l,2-di(4 -pyridyl)ethene was used as a reduction catalyst. The generated benzenetellurolate was employed in the synthesis of cyanophenyl phenyl tellurium compounds and of benzoylphenyl phenyl tellurium compounds. ... 

The limited solubility of long-chain alkyl halides in liquid ammonia makes it advantageous to evaporate the ammonia after the disodium telluride has formed and to dissolve the residue in an appropriate organic solvent. Ethanolic solutions of disodium telluride that had been prepared in liquid ammonia were used for the synthesis of the following heterocyclic tellurium compounds ... 

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