Alkoxohalogenotellurate(IV): Darstellung und Struktur von Tetraphenylphosphonium-trichloro(dioxo-ethylen-O.O')tellurat(rV) / Alkoxohalogenotellurates(IV): Preparation and Structure of Tetraphenylphosphonium Trichloro(dioxo-ethylene-O,O')tellurate(IV)

Abstract

Abstract The deprotonated glycolate dianion (OCH 2 CH 2 O) 2- is shown to react as a bidentate chelating ligand towards chalcogen(IV) halides. With TeCl 4 , the anion TeCl 3 (O 2 C 2 H 4 ) - is formed. According to a single crystal X-ray analysis of the tetraphenylphosphonium salt (P2 1 /c, a = 7.501, b = 26.328, c = 13.582 A, β= 104.55°, Z = 4) Te is in a tetragonal pyramidal (ψ octahedral) coordination with the alcoholate ligands in the apical (Te-O 1.919 Å) and in one of the equatorial positions (Te O 1.973 Å), the Te-Cl bond lengths being between 2.495 and 2.590 Å. The trans bond lengthening effect of the equatorial alcoholate ligand (i.e. the polarizing effect towards the lone pair) is unusually low. Vibrational spectra are reported.