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Thallium(I) complexes of dichalcogenido imidodiphosphinates {Tl[(EP(i)Pr(2))(2)N]}(n) (E = Te, Se, S): Synthesis, NMR
Jamie S Ritch1, Tristram Chivers
1Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, CanadaT2N 1N4.
Abstract:
The homoleptic thallium(i) complexes {Tl[(EP(i)Pr(2))(2)N]}(n) (, E = Te; , E = Se; , E = S) have been obtained in 70-86% yields from the reaction of TlOEt with (TMEDA)Na[(EP(i)Pr(2))(2)N] in CH(2)Cl(2) or Et(2)O. Complexes were structurally characterised in the solid state by single crystal X-ray diffraction and in solution by multinuclear NMR spectroscopy ((31)P, (77)Se, and (125)Te). The solid-state structures of , and are comprised of one-dimensional coordination polymers. In and there are two distinct environments for both the thallium centres and the [(EP(i)Pr(2))(2)N](-) ligands. The denticities of the selenium centres in the ligands of differ significantly from those of tellurium donor atoms in giving rise to different coordination geometries at the chalcogen atoms in these two complexes; however, both possess edge-sharing Tl(2)E(4) octahedra as structural units. By contrast, the sulfur analogue exhibits only one ligand environment with trigonal pyramidal geometries for both sulfur centres and a distorted tetrahedral geometry for thallium generating vertex-sharing four-membered Tl(2)S(2) rings.
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