Preparation and structures of tellurium(IV) halide complexes with thioether coordination.
The first chalcogenoether complexes of Te(iv) chloride and bromide are prepared by reaction of the thioether with a suspension of TeX(4) in anhydrous CH(2)Cl(2), and the products characterised by IR, Raman, (1)H and (125)Te{(1)H} NMR spectroscopy and microanalysis. The structures of the distorted octahedral chelate complexes [TeX(4){RS(CH(2))(2)SR}] (X = Cl or Br; R = Me or (i)Pr) and the centrosymmetric halo-bridged dimers [{X(3)(Me(2)S)Te}(2)(micro-X)(2)] (X = Cl or Br) involving Te(iv) are reported and the structures interpreted in terms of a three-centre-four-electron bonding model, with weak, secondary Te-S interactions. The structure of a unique Te(ii) thioether complex, [TeCl{(i)PrS(CH(2))(2)S(i)Pr}][Te(2)Cl(9)] obtained as a decomposition product from a sample of [TeCl(4){(i)PrS(CH(2))(2)S(i)Pr}], in which a Te(ii) thioether cation and Te(iv) chloride anion are weakly associated via micro(2)- and micro(3)-bridging Cl ligands, is also described. In this case distortions in the coordination environment at the Te(ii) ion are attributed to the effects of the Te-based lone pairs.
Gurnani
Chitra
C
School of Chemistry, University of Southampton, Southampton, UK SO17 1BJ.
Jura
Marek
M
Levason
William
W
Ratnani
Raju
R
Reid
Gillian
G
Webster
Michael
M