Polymeric structures containing self-assembled Li-dioxane networks; syntheses and crystal structures of [{Li(dioxane)(2.5)TaCl4S}(n)]center dot n/2 dioxane and [{Li-2(dioxane)(3)Cl}(n)][TaCl6](n)

The preparation and X-ray structure analyses of the compounds [{Li(dioxane) (2.5)TaCl4S}(n)].n/2 dioxane (1) and [{Li-2(dioxane)(3)Cl}(n)][TaCl6](n) (2 ) are described. The title compounds were isolated from a refluxed solution of TaCl5 and Li2S in dioxane/CH3CN. The compounds both crystallize in the monoclinic space group C2/c and contain a network of dioxane bridged Li+ ca tions. In 1, the polymeric network is further extended by TaCl4S units. The sixth coordination site of the central metal in these TaCl4S units is occu pied by an O-atom of one of the Li coordinating dioxane molecules. In contr ast, the [TaCl6](-) complex anion in 2 is isolated within a three-dimension al Li-Cl-dioxane network. (C) 2000 Elsevier Science S.A. All rights reserve d.