Synthesis and structural analysis of new organyltellurium halides with mixed oxidation states (II) and (IV) – [ArTe(L)]+[ArTeX4]–

SCHULZ LANG, E.; LEDESMA, G. N.; MACHADO, A.; ABRAM, U.

São Carlos (SP), Brasil.

Congreso; XII Brazilian Meeting on Inorganic Chemistry; 2004

Comité Organizador de XII Brazilian Meeting on Inorganic Chemistry

Recently, as part of our research in the coordination chemistry of organotellurium compounds, the synthesis and molecular structure of various organotellurium thihalogenides has been reported [1]. In the light of these previous results and to extend our studies of the molecular and intermolecular bondings in organotellurium trihalogenides, we report here the synthesis and characterization of two complexes, namely [PhTe(tmtu)][PhTeBr4](1) and [PhTe(tu)][PhTeI4](2), containing tellurium with mixed oxidation states (II) and (IV). This kind of compound is unusual due to the fact that both Te(II) and Te(IV) are present in the same molecule and share the halogens atoms. We found only one previously reported case, 2[Te2Br6(C3H8N2Se)2].3C2H3N.CH3OH, that has been isolated during the preparation of thin films of Te-Se alloys [2].In order to detect intra- or inter- molecular forces between heavy atoms, a structural study in the solid state was carried out with single crystal X–ray diffraction. The X-ray measurements of 1 and 2 in the space group P were choosen on the basis of statistics and later justified by the successful refinements(R1=0,0597 and 0,0420; wR2= 0,1707 and 0,1165 for 1 and 2 respectively). It was assumed that the presence of intermolecular bonds in these and in other related compounds allow them to be viewed as supramolecular assemblies In this way, the relation between crystalline structure and supramolecular organization could be better understood. Finally, some of the observed characteristics in the spatial arrangement of these derivatives suggest the existence of anisotropic properties.References[1] – G. N. Ledesma, E. S. Lang, U. Abram, J. Organomet. Chem., 689(12), 2004, 2092-2095.[2] – H. M. K. K. Pathirana, J. H. Reibenspies, E. A. Meyers, R. A. Zingaro, Acta Cryst. C47, 1991, 516-519.Acknowledgements: CNPq, FAPERGS.