From Hydrogen Telluride

Digermylcarbodiimides reacted at 20° with hydrogen telluride forming digermyl tellurium compounds.  

Bis[methylgemiyl] Tellurium 0.36 g (1.62 mmol) of bis[methylgermyl]carbodiimide are condensed into a 150ot/, greaseless vessel. The vessel is cooled to —196°, excess hydrogen telluride, prepared by acidic hydrolysis of aluminum telluride, is condensed into the vessel, and the mixture is carefully warmed to 20° (the mixture is cooled if the reaction becomes too vigorous). After 1 h the reaction mixture is fractionated under reduced pressure using cold traps to collect the product yield 0.31 g (62%). 

Hydrogen telluride passed into a solution of l,4-diiodooctakis[/-butyl]tetrastannane in toluene formed air-stable octakis[t-butyl]telluratetrastannolane.  

5-Octakis[r-butyl]-l,2,3,4,5-telluratetrastannolane All operations are performed under an argon atmosphere with oxygen-free solvents. Hydrogen telluride is passed for 1 h through a solution of 5.0 g (4.2 mmol) of l,4-diiodo-l,l,2,2,3,3,4,4-oetakis[t-butyl]tetrastannane in a mixture of 100 m/of toluene and 1 ml of triethylamine. The mixture is then filtered to remove preeipitated triethylammonium iodide, the solvent is evaporated from the filtrate, and the residue is recrystallized from chloroform/hexane yield 2.4 g (55%) m.p. 170° (dec.). 

Dilithium telluride, prepared from lithium and tellurium in liquid ammonia or from tellurium and lithium triethylborohydride, reacted with alkylhalosilanes and -germanes to yield disilyl and digermyl tellurium derivatives. 

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The method of Bruylants and Desmet 8 was similar to the foregoing. Tellurium prepared from hydrogen telluride was treated with nitric acid and the resulting dioxide separated by evaporation, calcined, and... 

Sodium hydrogen telluride, (NaTeH), prepared in situ from the reaction of tellurium powder with an aqueous ethanol solution of sodium borohydride, is an effective reducing reagent for many functionalities, such as azide, sulfoxide, disulfide, activated C=C bonds, nitroxide, and so forth. Water is a convenient solvent for these transformations.28 A variety of functional groups including aldehydes, ketones, olefins, nitroxides, and azides are also reduced by sodium hypophosphite buffer solution.29... 

When the conditions are controlled properly, Zn can mediate the reduction of the C-C double bond of a, (3-unsaturated carbonyl compounds in the presence of a nickel catalyst in aqueous ammonium chloride (Eq. 10.7). The use of ultrasonication enhances the rate of the reaction.15 Sodium hydrogen telluride, (NaTeH), prepared in situ from the reaction of... 

Organyl tellurols are very unstable compounds owing to their extreme sensitivity to oxygen, giving the corresponding ditellurides. The first short-chain alkyltellurols (C1-C4) have been isolated as yellow liquids with an obnoxious odour, from the reaction of aluminium telluride and hydrogen telluride, respectively, with alcohols and aUcyl bromides. Aryltellurols seem not to have been isolated. As shown in Sections 3.1.3.2 and 3.2.2, aryl tellurolates are... 

The reduction of azo compounds to hydrazo compounds is also achieved by means of aryltellurols or sodium hydrogen telluride. The last reagent (generated from NaBH4 and... 

The reaction has been suggested as involving a one-electron transfer from sodium hydrogen telluride to the nitro compound followed by the detachment of a nitrite anion from the resulting radical anion. 

Phenacyl esters, easily prepared from carboxylic salts and phenacyl bromide nnder phase transfer catalysis, regenerate the original carboxylic acid by treatment with sodinm hydrogen telluride in DMF. ... 

The allyl group, a less familiar protective group for carboxylic acids, can be easily removed from esters by treatment with sodium hydrogen telluride. In contrast to the preceding methods, ethanol has been employed as the solvent. 

Fig. 3.5.6 Absorbance spectra of 190-layer cadmium-10, 12-diynoatc LB films after exposure to (a) hydrogen sulfide, (b) hydrogen selenide, or (c) hydrogen telluride. The spectra have been corrected for background (quartz and film). (From Ref. 31.)...

Hydrogen tclluride, H,Te. Mol. wt. 129.62. unstable gas. The reagent can be generated in situ from aluminum telluride, Al2Te3 (Alfa), and water. 

Hydrogen telluride is also obtainable from the metallic tellurides, for example, from magnesium, aluminium, zinc and iron tellurides. These are decomposed by water or by a non-oxidising acid such as dilute... 

Some nucleophilic species of tellurium are used to regenerate a functional group from its protected form. For example, carboxylic acids 51 are regenerated in high yields from their alkyl and benzyl esters by using sodium hydrogen telluride or sodium telluride (Scheme 27).21,30,114,115... 

Sodium hydrogen telluride, prepared from tellurium and sodium borohydride in aqueous or aqueous/ethanolic medium, reacted with 1,4-diiodooctaphenyltetragermane3, chlorotri-phenylstannane4, 1,2-dichlorotetramethyldistannane5, dichlorodimethylstannane6, and with chlorotriphenylgermane7. 

Bis[triphcnylstannyl] Tellurium4 A solution of sodium hydrogen telluride is prepared from tellurium and sodium borohydride in aqueous ethanol. A benzene solution of chlorotriphenylstannane (2 mol/mol of tellurium) is added dropwise, the benzene layer is separated, and evaporated to dryness. The residue is recrystallized several times from diethyl ether/hexane m.p. 150°. 

Tris[tetraethylammonium] Tetrakis [benzenetellurolate(tellurido) ferrate]3 Under an atmosphere of nitrogen, 4.54 g (4 mmol) of bis[tetraethylammonium] tetrakis[benzenetellurolato]ferrate(II) dissolved in 40 m/ acetonitrile are dropped into a solution of sodium hydrogen telluride in 30 ml acetonitrile. (The sodium hydrogen telluride was prepared from 0.51 g (4.0 mmol) tellurium powder and a three-fold excess of sodium borohydride in ethanol, evaporation of the ethanol, and dissolution of the residue in 30 ml acetonitrile.) The... 

Hydrogen telluride, generated in situ from aluminum telluride in aqueous tetrahydrofuran containing sulfuric acid, reacted with aliphatic aldehydes to produce dialkyl ditellurium compounds in yields of aproximately 50%. Strong acids are required to obtain acceptable yields of ditellurium compounds. Weak acids (acetic acid, chloroacetic acid) reduce the yields to approximately 10%. In a basic medium (triethylamine), no ditellurium derivative was formed the major product was the alcohol. 

In all these reactions alkanols were formed in yields of a few percent. The ditellurium compounds are postulated to be the products of the reaction of hydrogen telluride with the telluroaldehydes that are formed as intermediates from the aldehydes and hydrogen telluride1. 

Bis[l-naphthyl] Ditellurium2 To a stirred solution of 0.15 mol of naphthyl lithium in 200 ml of anhydrous diethyl ether under an inert atmosphere are added in small portions 18 g (0.14 mol) of commercial tellurium powder. After completion of the addition, the mixture is stirred and heated under reflux for 30 min and then poured into aqueous 6 molar hydrochloric acid containing ice. This operation must be performed in a well-ventilated hood to avoid exposure to hydrogen telluride. Air is then bubbled through the filtered mixture which is subsequently extracted several times with diethyl ether. The extracts arc dried with magnesium sulfate and evaporated. The residue is recrystallized from petroleum ether (b.p. 20-40°) yield 66% m.p. 119- 122°. Similarly prepared were the following diaryl ditellurium compounds ... 

Hydrogen telluride, prepared from aluminum telluride and 2 molar hydrochloric acid, added to the double bond in vinyl cyanide and formed bis[2-cyanoethyl tellurium1. 

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