A New Polymeric Antimony(III) Oxoalkoxide, [Sr2Sb4O(OEt)14]n: The Synthesis and Molecular Structure

✍ Scribed by U. Bemm; K. Lashgari; R. Norrestam; M. Nygren; G. Westin

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 304 KB
• Volume: 108
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1994.1038

✦ Synopsis

A new bimetallic oxoalkoxide, with composition (\mathrm{Sr}{2} \mathrm{Sb}{4} \mathrm{O}(\mathrm{OEt}){14}), has been synthesized by reacting (\mathrm{Sr}(\mathrm{OEt}){2}) with an excess of (\mathrm{Sb}(\mathrm{OEt}){3}) in toluene-ethanol under a dry nitrogen atmosphere. Colorless transparent crystals of the alkoxide have been studied by single crystal X-ray diffraction methods. The crystals have a monoclinic space group symmetry (P 2{1} / n), with (a=11.609(3) \AA), (b=22.006(5) \AA, c=18.948(5) \AA, \beta=105.08(2)^{\circ}, V=4673(2)) (\AA^{3}, Z=4, D_{x}=1.861(1) \mathrm{g} \cdot \mathrm{cm}^{-3}) and (M_{\mathrm{r}}=1309.1). From the X-ray diffraction data collected at (163(1) \mathrm{K}), refinements of the derived structure model against the amplitudes of the 3745 most significant reflections converged at an (R)-value of 0.043 . The crystal structure consists of infinite parallel chains extending in the [100] direction. The polymer chains are formed by units of composition (\left[\mathrm{Sr}{2} \mathrm{Sb}{3} \mathrm{O}(\mathrm{OEt}){10}\right]^{+}), that are linked by (\left[\mathrm{Sb}(\mathrm{OEt}){4}\right]^{-})groups through pairs of bridging ethoxy oxygen atoms. The parallel chains are approximately close packed. The oxygen coordination polyhedra around two five-coordinated antimony atoms share a common face. The (\mathrm{Sr}) atoms are seven-coordinated by oxygen atoms. As all the ethoxy oxygen atoms are two-coordinated and the oxo oxygen four coordinated by the metal ions, the formula of the present strontium-antimony oxoethoxide can be written (\left[\mathrm{Sr}{2} \mathrm{Sb}{4}\left(\mu_{4}-\mathrm{O}\right)\right.) (\left.(\mu-\mathrm{OEt}){14}\right]{n} . \quad 1994) Academic Press, Inc.