Synthesis and spectroscopic characterization of new mixed ligand organotellurium(IV) compounds employing dithiocarbamates and imidotetraphenyldithiodiphosphinates. Crystal structure of [C4H8Te(S2CNEt2){(SPPh2)2N}], [C4H8Te(S2CNC5H10){(SPPh2)2N}] and [C4H8

The synthesis of new mixed ligand organotellurium(IV) compounds, [C4H8Te(S2CNEt2){(SPPh2)2N}] (1), [C4H8Te(S2CNC5H10){(SPPh2)2N}] (2), [C4H8Te(S2CNC4H8O){(SPPh2)2N}] (3) and [C4H8Te(S2CNC4H8S){(SPPh2)2N}] (4), was achieved. They were characterized by FAB+ mass spectrometry, IR, 1H-, 13C-, 31P- and 125Te-NMR spectroscopy. The crystal structures of 1, 2 and 4 were determined by X-ray diffraction. The solid state structures show that the coordination geometry can be described as the sawhorse structure typical for Te(IV) in which the lone pair is regarded as stereochemically active and occupying an equatorial position in a distorted trigonal bipyramid. Both types of ligands exhibit an anisobidentate chelating coordination mode on interaction with the tellurium center. If the aniso-bonded donor atoms are included in the coordination sphere, the coordination number increases to seven and the environment at Te can be described as the 1:2:2:2 structure. No intermolecular interaction was observed.