Ruthenium-Assisted Tellurium Abstraction in Bis(thiophen-2-yl) Ditelluride

The reaction of [RuCl2(CO)(3)](2) and Te(2)Tpn(2) (Tpn=thiophen-2-yl, C4H3S) in the absence of light resulted in the formation of cct-[RuCl2(CO)(2)(TeTpn(2))(2)] (1) [cis(Cl)-cis(CO)-trans(TeTpn(2))] and TeTpn(2) (2) together with the precipitation of tellurium. The complex 1 and the monotelluride 2 were characterized by NMR spectroscopy and single-crystal X-ray diffraction. The decomposition of Te(2)Tpn(2) to TeTpn(2) has been monitored by Te-125 NMR spectroscopy and seemed to be faster than the ligand substitution in [RuCl2(CO)(3)](2) by TeTpn(2). A catalytic cycle is proposed for the decomposition of Te(2)Tpn(2) to TeTpn(2) based on the PBE0-D3/def2-TZVP calculations.