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Benzene Tellurium Compounds

Diorganophosphano trimethylsilyl tellurium compounds rearrange in benzene solution to give the symmetrical bis[diorganophosphano] tellurium and bis[trimethylsilyl] tellurium compounds2,6. [Pg.28]

Upon irradiation with a mercury lamp, solutions of aryl benzoyl tellurium compounds in benzene form the corresponding diaryl ditelluriums3,4. [Pg.279]

When phenyl tellurium trichloride or 4-phenoxyphenyl tellurium trichloride were reacted with sodium 2-benzoyl-5-methoxyphenoxide in a refluxing mixture of benzene/methanol, compounds were obtained that contained chloride and phenoxide groups3. [Pg.338]

Diorgano tellurium compounds with carbonyl groups or C — C double bonds next to the C — Te — C groups are rather labile. For example, allyl methyl tellurium decomposes in light at 60 to 80° to tellurium, 1 -butene, and 1,5-hexadiene. In benzene solution at 60° in the dark this unsymmetrical diorgano tellurium symmetrizes to dimethyl tellurium and dialkyl tellurium within 10 minutes8. 2,5-Dihydrotellurophenes deposit tellurium at 20° while photolysis of an ethanolic solution at 300 nm produced tellurium and isoprene but no cyclobutene9. [Pg.478]

Diorgano tellurium compounds are easily oxidized by elemental halogens to diorgano tellurium dihalides. Generally, the reactions are carried out with solutions of the reagents in inert organic solvents such as diethyl ether, methanol, acetonitrile, dichloromethane, chloroform, carbon tetrachloride, fluorotrichloromethane, benzene, or toluene. Often, the diorgano tellurium dihalides precipitate quantitatively from the reaction mixture. Soluble products are isolated by evaporation of the solvent or by addition of petroleum ether or hexane. [Pg.553]

Butyl Phenyl Tellurium Dibromide9 Into a nitrogen-flushed 100 m/ flask fitted with a magnetic stirrer is placed a solution of 2.0 g (7.6 mmol) of butyl phenyl tellurium in 10 ml of carbon tetrachloride. A solution of 1.22 g (7.6 mmol) of bromine in 25 ml of carbon tetrachloride is added dropwise to the stirred solution of the tellurium compound. The solvent is evaporated under vacuum at 20°, the oily residue is dissolved in 10 ml of benzene, and then hexane is added dropwise until no more precipitate forms. The yellow crystals are filtered off and dried yield 3.05 g (95%) m.p. 70°. [Pg.555]

Diorgano tellurium compounds are easily converted to diorgano tellurium diiodides upon treatment with elemental iodine. The reactions are carried out with solvents such as benzene, chloroform, carbon tetrachloride, and 1,2-dichloroethane. Because iodine is much less reactive than chlorine or bromine, the reactions can be performed at 20 . The diorganyl tellurium diiodides generally precipitate upon mixing the reagents. [Pg.556]

Diorgano tellurium compounds can be easily converted to diorgano tellurium dihalides in reactions with sulfuryl chloride, bromide, and iodide. Carbon tetrachloride, dichlorometh-ane, diethyl ether, petroleum ether, or benzene have been used as reaction media. Chlorinations with sulfuryl chloride, a liquid reagent, avoid the use of gaseous chlorine. Required amounts of sulfuryl chloride can be more easily measured than those of chlorine. Sulfur dioxide formed during the reaction escapes the reaction mixture as a gas, thus facilitating the isolation of the product. For these reasons, sulfuryl chloride has been frequently used, whereas sulfuryl bromide and iodide5-6 have been only infrequently employed. [Pg.558]

Tris[4-methylphenyl] bismuth difluoride fluorinated diaryl tellurium compounds in benzene solution2 3. [Pg.560]

Alkyl halides and arenetellurolates react to form alkyl aryl tellurium compounds, which are easily converted to alkyl aryl tellurium dihalides. Heating of these tellurium dihalides with triphenyl tin hydride in benzene results in the formation of alkanes in high yields. The alkyl aryl tellurium dihalides are more readily reduced than the alkyl aryl telluriums1. [Pg.578]

Bis[4-methoxyphenyl] tellurium dibromide is an intermediate in the debromination of vic-dibromides to olefins in a water/benzene system containing potassium disulfite. The organic tellurium compound added as bis[4-methoxyphenyl] tellurium catalyzes this reaction1. [Pg.583]

Diaryl tellurium compounds are cleanly oxidized at 20° to diaryl tellurium diacetates by lead tetraacetate in benzene or toluene, The isolation of the diaryl tellurium diacetates, which are soluble in aromatic hydrocarbons, is facilitated by the precipitation of lead diacetate8. [Pg.605]

Most of the diorgano alkylidene tellurium compounds thus far reported derive their alkylidene group from 5,5-dimethyl-l,3-dioxocyclohexane. These diorgano cyclohexyl-idene tellurium compounds are colorless, crystalline substances that are stable at 20° and readily soluble in benzene, carbon tetrachloride, and dichloromethane2,3. Single crystal X-ray diffraction showed that the tellurium atom in bis[4-methoxyphenyl] 5,5-dimethyl-l,3-dioxo-2,2-cyclohexylidene tellurium occupies the apex of a trigonal pyramid4. [Pg.715]

Diaryl tellurium dihalides condense with 5,5-dimethyl-l, 3-dioxocyclohexane in benzene in the presence of triethylamine to give cyclohexylidene diaryl tellurium compounds. Whether a reaction occurs at 20° or requires elevated temperatures is determined by the substituents on the aryl groups. Dimethyl tellurium dichloride and aryl methyl tellurium dichlorides react at 20°. [Pg.717]

Tellurium tetrafluoride and tellurium tetrachloride reacted exothermically with N,N-bis[trimethylsilyl]acetamide and with A, A -bis[trimethylsilyl]arenesulfonamides in benzene to precipitate the corresponding diimino tellurium compounds. ... [Pg.76]

Tellurium dioxide dissolved in dilute hydrochloric acid and treated with an aqueous solution of sodium 3-oxapentamethylenedithiocarbamate in a molar ratio 1 4, formed a precipitate of tellurium tetrakis[3-oxapentamethylenedithiocarbamate]. The compound was recrystallized from benzene. The crystals had three molecules of benzene associated with each molecule of the tellurium compound . [Pg.108]

Sodium benzenetellurolate is arylated in liquid ammonia via photoinduced reactions with aryl halides Aryl iodides reacted with sodium benzenetellurolate in the presence of copper(I) iodide in hexamethylphosphoric triamide (but not in DMF or DMSO) to produce aryl phenyl tellurium compounds. However, lithium benzenetellurate reacted with 1,2-bromoiodobenzene and lithium methane tellurolate with 1,2-dibromobenzene in tetrahydrofuran at 20° to yield l,2-bis[organotelluro]benzenes . [Pg.176]

Irradiation of benzene solutions of 7e-aryl arenetellurocarboxylates with light from a mercury lamp generated radicals via homolytic cleavage of the Te—CO bond. The free radicals subsequently formed aldehydes, diorgano tellurium compounds, and diorgano ditellurium compounds via hydrogen abstraction, dimerization and elimination of tellurium, or dimerization -. The products of the photo-induced reaction of Te-4-methylphenyl 2-methylthiobenzene(tellurocarboxylate) are given as an example . ... [Pg.504]

Diorgano tellurium oxides and organic compounds with an activated methylene group condensed in chloroform or benzene to produce diorgano alkylidene tellurium compounds. [Pg.717]


See other pages where Benzene Tellurium Compounds is mentioned: [Pg.209]    [Pg.239]    [Pg.256]    [Pg.56]    [Pg.416]    [Pg.504]    [Pg.164]    [Pg.416]    [Pg.926]    [Pg.30]    [Pg.21]    [Pg.85]    [Pg.377]    [Pg.152]    [Pg.80]   


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Tellurium compounds

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