Crystal and molecular structure of bis(2-isotropyliminomethinylphenyl) telluride

Scientific-Research Institute of Physical and Organic Chemistry, Rostov State University. A. N. Nesmeyanov Institute of Heteroorganic Compounds, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 32, No. 3, pp. 104–106, May–June, 1991.     

Nitrogen-tellurium-containing heterocycles. 4. X-ray structure of 2-phenylbenzotellurazole

The crystal and molecular structure of 2-phenylbenzotellurazole is determined by x-ray methods. The heterocyclic fragment of the molecule is planar. The dihedral angle between planes of the heterocycle and the 2-phenyl substituent is 31.2. Somewhat shortened Te-N intermolecular ocntacts (3.43 å) are seen in the crystal. These do not substantially affect the physical properties of the compound.For Communication 3, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1690–1692, December, 1989.     

A Study of Competitive Coordination of Benzochalcogenazole Ligands by Heteronuclear NMR Spectroscopy

Complexes of 2-methyl(phenyl)benzo-1,3-tellurazole and 2-methyl(phenyl)benzo-1,3-selenazole with tungsten pentacarbonyl and boron trifluoride were studied by heteronuclear NMR spectroscopy (¹H, ¹³C, ⁷⁷Se, and ¹²⁵Te). The coordination mode of the ambident ligand can be determined from the coordination shifts of the ¹²⁵Te and ⁷⁷Se NMR signals: upfield at coordination via Te and Se atoms and downfield at N coordination.     

Reactions of 10-telluroniaanthracene perchlorates with nucleophiles

10-Telluroniaanthracene perchlorates react with nucleophiles (X^–=halide, hydroxide, methoxide) via intermediate free telluroxanthyl radicals. With 9-aryl-10-telluroniaanthracene perchlorates, high yields of 9-aryl-9-X-telluroxanthenes are obtained, but with 10-telluroniaanthracene the principal product is 9,9-bis(telluroxathenyl) as a result of rapid competitive dimerization.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 691–695, May, 1989.     

Synthesis of benzo-1,3-ditellurole and its precursors

Poly(o-phenyleneditelluride) 6 has been prepared by the reduction of 1,2-bis(trichlorotelluro)benzene obtained by treatment of 1,2-bis(trimethylsilyl)benzene with TeCl₂. The reduction of 6 with NaBH₄ in ethanol solution affords sodium benzene-1,2-ditellurolate, which, upon treatment with methylene bromide, forms benzo-1,3-ditellurole in 40–47% yield. Benzo-1, 3-ditellurole has also been synthesized in 18–20% yeild by the reaction of 1,2-bis(trimethylslyl)benzene with bis(trichlorotelluro)methane, with subsequent reduction of the product, 1,1,3,3-tetrachlorobenzo-1,3-ditellurole.     

Telluraxanthene

Telluraxanthene was obtained by intramolecular electrophilic cyclization of 2-trichlorotelluriodiphenylmethane with subsequent reduction of the intermediately formed 10,10-dichlorotelluraxanthene. The chemical reactions that occur at the tellurium atom and the methylene group of telluraxanthene were studied. The lower limit of the activation energy of pyramidal inversion at the onium tellurium atom in telluroniaxanthenyldimedone ylid was determined by PMR spectroscopy.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1342–1349, October, 1980.     

Synthesis of 2-substituted benzo-1,3-ditelluroles

A method for the synthesis of 2-phenylbenzo-1,3-ditellurole by the reaction of disodiumo-benzeneditellurolate with benzylidene chloride was proposed. 2-Methylbenzo-1,3-ditellurole and benzo-1,3-ditellurole-2-carboxylic acid were prepared by the reaction of 2-lithiobenzo-1,3-ditellurole with MeI and CO₂, respectively. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1132–1134, June, 2000.     

Reaction of Diaryl Telluroxides with HBF4

Russian Journal of Organic Chemistry -