Reactivity of bis[{2,6-(dimethylamino)methyl}phenyl]telluride with Pd(ii) and Hg(ii): isolation of the first Pd(ii) complex of an organotellurenium cation as a ligand

Abstract

Intramolecularly coordinated homoleptic diorganotelluride L₂Te (6) [where L = 2,6-(Me₂NCH₂)₂C₆H₃] was synthesized and its reactions with Pd(II) and Hg(II) precursors were explored. The reaction of 6 with SO₂Cl₂ and K₂PdCl₄ resulted in the formation of the first example of a Pd(II) complex, LTePdCl₃ (7), with any organotellurenium cation (LTe⁺) as a ligand. When diorganotelluride 6 was reacted with HgCl₂, the reaction afforded the tellurenium cation [LTe]₂⁺[Hg₂Cl₄]²⁻ (8). The reaction of 6 with [(PhCN)₂PdCl₂] afforded the Pd(II)–telluroether complex L₂TePdCl₂ (9). Diorganotelluride 6 and complexes (7–9) were characterized by single-crystal X-ray diffraction studies. The crystallographic studies suggested that in complex 7, the Te(II) center was ‘ambiphilic’ in nature in the sense that while Te(II) acted as a donor to the Pd(II) ion, at the same time, it accepted electrons from the N-donor side arms via secondary bonding interactions. The donation of electrons from Te(II) to Pd(II) in complex 7 was further substantiated by Natural Bond Order (NBO) analysis.