Organotellurium compounds,

These facts, together with many other examples of the peculiar chemical behavior of organotellurium compounds (95UK527), emphasize their specific reactivity and explain why a number of methods developed for preparation of organosulfur and organoselenium compounds are inapplicable for their tellurium analogues. 

Various classes of organotellurium compounds in aprotic solvents have been studied as to their electrochemistry, whereas more limited are the reports on the electrochemistry of tellurium and its inorganic compounds in non-aqueous solvents [54, 55]. 

K. Irgolic, Organotellurium Compounds, D. Klamann (ed), Thieme, Hamburg, 1990. 

One- and two-electron oxidations and reductions of organoselenium and organotellurium compounds, 39, 79... 

Several new types of Ge-O-bonded species have appeared and some new methods for the formation of such bonds have been described. Germoxanes can be obtained via reaction of triorganobromogermanes with oxygen in the presence of organotellurium compounds (Equation (127)).164 The germapropadiene 4 reacts with alcohols to provide alkoxides 70 (Equation (128)) or benzaldehyde to yield a 1,2-oxagermetane 71 via a [2 + 2]-addition (Equation (129)), which exhibits unusual thermal stability for an unencumbered oxagermetane.16... 

One-electron oxidation of organoselenium and organotellurium compounds results in initial formation of a radical cation (equations (19) and (20)). The eventual fate of the radical cation depends on several variables, but is typically a Se(lV) or Te(lV) compound. The scope of this section will be the one-electron oxidation of selenides and tellurides that are not contained in a heteroaromatic compound, and ones in which the Se and Te are bonded to two carbons, rather than to other heteroatoms. Tellurium- and selenium-containing electron donor molecules have been reviewed. 

Organochalcogen(II) compounds, 100-102 Organochalcogen(IV) compounds, 100-102 Organoselenium compounds dehalogenation reactions, 96 electrochemical reduction, 113-117 haloperoxidase-like activity, 108-113 with odd number of ligands, 100-102 one-electron oxidation, 117-118 oxidation of thiols, 102-106 redox reactions, 79-80 thioperoxidase-like activity, 108-113 Organotellurium compounds... 

This chapter is devoted mainly to the preparation of those classes of organotellurium compounds that have been more systematically investigated in past years, owing to their peculiar role as reagents or intermediate in organic synthesis, including compounds of structural, biological or theoretical interest. 

Diorganyl tellnrides, which as shown in Section 3.1 are the primary products of several methods for the synthesis of organotellurium compounds, can easily be converted into the corresponding dihalides by the simple addition of halogens. 

CONVERSION OF ORGANOTELLURIUM COMPOUNDS INTO TELLURIUM-FREE ORGANIC COMPOUNDS... 

Detelluration of organotellurium compounds with the formation of new C-C bonds (carbodetelluration)... 

Palladium-catalysed cross-coupling of organotellurium compounds with hypervalent iodonium salts... 

Detellurative carbonylation of organotellurium compounds preparation of carboxylic acids... 

The transformation of a carbon-tellurium bond into a carbon-halogen bond has been achieved in several types of organotellurium compound. 

Special attention was focused on organotellurium compounds as precursors for carbon-centred radicals. 

Intensive investigations have been directed recently to group-transfer imidoylation of organotellurium compounds with isonitriles. " ... 

It was found that a variety of stabilized carbon-centred radicals such as glycosyl, benzyl, a-amino, a-alcoxy, a-carbalcoxy and aryl derivatives, generated from the corresponding organotellurium compounds, are effectively trapped by the isonitriles. 

Carbon-centred radicals, generated under photo-thermal conditions from organotellurium compounds, react with a variety of quinones to afford the mono addition products in good yields. ... 

Reaction of organotellurium compounds with quinones (typical procedure, 2-benzyl-l, 4-benzoquinone) A solution of benzyl p-methylphenyl telluride (111 mg, 0.36 mmol) and 1,4-benzoquinone (78.0 mg, 0.72 mmol) in benzene (0.6 mL) in a Pyrex tube was irradiated with a 200 W high-pressure mercury lamp at 100°C for 1 h. After the solvent was removed under reduced pressure, the crude mixture was purified by flash chromatography (silica gel 6.4 g elution with 5% ethyl acetate in hexane) to give the product in 57% yield. 

Organotellurium compounds as initiators for controlled living radical polymerization... 

Toxicity data on organotellurium compounds are still scarce in the hterature, in contrast with those of organoselenium compounds. 

Although some authors have informed that organotellurium compounds are less toxic than their selenium co-partners, further data indicated in opposition that organotellurium compounds are more toxic than organoselenium compounds. ... 

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