Síntese, reatividade e caracterização estrutural de haletos de telúrio e ariltelurenila com estados de oxidação incomuns ou mistos.

Abstract

This work presents a study related to the halogenation of diarylditellurides (RTe)2 in order to obtain tellurium and aryltellurenyl halides with unusual or mixed oxidation states. Although regarded as essentially unstable, the aryltellurenyl monohalides (RTeX) were generated in situ and captured from the reaction milieu in many ways, forming stable adducts or intermediates for the synthesis of new tellurium derivatives. Overall, the twenty-one compounds presented in this paper can be summarized into five distinct classes: {(Q+)n[RTeI2]−(I3)− n-1}; {(RTeI3)(RTeI)n, n = 1,2}; {R2Te-Te(I)R}; {RTe Te(X2)R, X = Cl, Br and I} and {(Q+)2[Te2I10]2−}. The determining factor for the formation of the first four classes is the nature of the organic group (R) of the starting ditelluride. However, all of these compounds are subjected to decomposition, inasmuch the bond C Te has the lowest energy among the carbon chalcogen bonds, and this feature also contributes to the formation of the fifth class, the tellurium halides {(Q+)2[Te2I10]2−}. Structurally, these compounds were characterized by single crystal x-ray diffraction, which showed the presence of intra- or intermolecular secondary bonds Te···Te, Te···O, Te···X, X···X (X = halogen), interactions Te···p aryl, beyond hydrogen bonds N H···X, responsible for the organization of supramolecular assemblies in the solid state.