A flexible expanded heterocorrole: Tellura[22]porphyrin(6.1.1.0)

An expanded heterocorrole, meso-tetraaryl-tellura[22]porphyrin(6.1.1.0), containing a bipyrrole moiety and a six-carbon long link, has been synthesized. The reaction path proceeds through a controlled acid-promoted extrusion of one tellurium atom from meso-aryl-26,28-ditellurasapphyrin, leading to a structure where one tellurophene ring of the substrate is replaced by a bridging acyclic four-carbon unit. This aromatic porphyrin-annulene hybrid is conformationally flexible in solution, on account of the C4 unit adopting two different configurations: trans–cis–trans or all-trans. Studies of the dynamic behavior of tellura[22]porphyrin(6.1.1.0) in solution were performed by means of 1H and 125Te NMR spectroscopy. The X-ray structure of the all-trans form with trapezoid macrocyclic skeleton is also presented.

Synthesis and X-ray Characterization of Organotelluroxane

The reactions of diethyl tellurium (IV) diiodide [(C2H5)2TeI2 ] with conc. HNO3 afford diorganotelluroxane. The X-ray crystal structures of organotelluroxane reveal the immediate co-ordination geometry about the central tellurium atom to be pseudotrigonal bipyramidal ( TBP) with one stereochemically active electron lone pair. The supramolecular associations of the diorganotelluroxanes (IV) generated through Te---O secondary bonds.

Building new discrete supramolecular assemblies through the interaction of iso-tellurazole N-oxides with Lewis acids and bases

The supramolecular macrocycles spontaneously assembled by iso-tellurazole N-oxides are stable towards Lewis bases as strong as N-heterocyclic carbenes (NHC) but readily react with Lewis acids such as BR3 (R = Ph, F). The electron acceptor ability of the tellurium atom is greatly enhanced in the resulting O-bonded adducts, which consequently enables binding to a variety of Lewis bases that includes acetonitrile, 4-dimethylaminopyridine, 4,4′-bipyridine, triphenyl phosphine, a N-heterocyclic carbene and a second molecule of iso-tellurazole N-oxide.

Reactions of nitroxides 16. First nitroxides containing tellurium atom

Five- and six-membered nitroxides with a tellurium containing moiety were synthesized by the addition of nitroxyl amines to phenyltellanyl alkylene isothiocyanates.

1,1,2,3,4,5 - Hexahydro Tellurophene [C4H8Te(II)] and 1,3-Dihydro-2λ4-Benzotellurole [C8H8Te(II)] Derivatives

Convenient route of synthesis of the type R₂TeX′SY and R₂Te(CH₃)X′c were dove loved by the reactions of R₂Te(II) [R₂ = C₄H₈, C₈H₈] with IX′S (X′S= Cl, Br), RI (R = CH₃, C₂H₅) and CH₃X″c (X″c = Cl, Br, NO₃, C₆H₅OCO).These complexes have been characterised through elemental analysis (Table 1) and ¹H NMR spectral data (Table 2). The ¹H NMR spectra of C₄H₈TeICl, C₄H₈TeIBr, C₄H₈TeCH₃I, C₄H₈TeCH₃Cl, C₄H₈TeCH₃Br, C₄H₈TeCH₃NO₃, C₄H₈TeCH₃OCOC₆H₅, C₈H₈TeCH₃I, and C₈H₈Te -C₂H₅I have been recorded in CDCl₃ at 300 MHz. The study indicates that the heterocycles of C₄H₈Te(II) and C₈H₈Te(II) undergo oxidative addition reactions readily resulting in the increase in the oxidation number of central tellurium atom.