Trisubstituted heteropolytungstates as soluble metal oxide analogs. Isolation and characterization of [(C{sub 5}Me{sub 5})Rh{center_dot}P{sub 2}W{sub 15}Nb{sub 3}O{sub 62}]{sup 7{minus}} and [(C{sub 6}H{sub 6})Ru{center_dot}P{sub 2}W{sub 15}Nb{sub 3}O{sub 62}]{sup 7{minus}}, including the first crystal structure of a Dawson-type polyoxoanion-supported organometallic complex
The heteropolyoxoanion-supported complexes [(C{sub 5}Me{sub 5})Rh{center_dot}P{sub 2}W{sub 15}Nb{sub 3}O{sub 62}]{sup 7{minus}}, 1, and [(C{sub 6}H{sub 6})Ru{center_dot}P{sub 2}W{sub 15}Nb{sub 3}O{sub 62}]{sup 7{minus}}, 2, have been prepared by addition of [(C{sub 5}Me{sub 5})Rh(CH{sub 3}CN){sub 3}]{sup 2+} or [(C{sub 6}H{sub 6})Ru(CH{sub 3}CN){sub 3}]{sup 2+} to a solution of P{sub 2}W{sub 15}Nb{sub 3}O{sub 62}{sup 9{minus}} in acetonitrile. Isolation of these complexes as homogeneous, yellow solids as their all-[(n-C{sub 4}H{sub 9}){sub 4}N]{sup +} salts (for 1) or as complexes with mixed [(n-C{sub 4}H{sub 9}){sub 4}N]{sup +}/Na{sup +} cation composition (for 1 and 2) was accomplished by repeated reprecipitation from acetonitrile with ethyl acetate. Molecular formulas for these complexes were established by complete elemental analyses, in conjunction with a sedimentation-equilibrium molecular-weight measurement. Further characterization in solution relied heavily on multinuclear NMR spectroscopy. The solution data are in accord with [(C{sub 5}Me{sub 5})Rh]{sup 2+} and [(C{sub 6}H{sub 6})Ru]{sup 2+} being supported on three niobium-bridging oxygens on the {open_quotes}Nb{sub 3}O{sub 9}{sup 3{minus}}{close_quotes} surface of the heteropolyoxoanion. The structural characterization of 1 in the solid state was accomplished by a single-crystal X-ray structural analysis. The Rh atom in 1 lies on the polyoxoanion`s 3-fold axis within experimental error and is bonded to the three Nb-O-Nb bridging oxygen atoms (Rh-ONb{sub 2} 2.06 {angstrom}) that cap the P{sub 2}W{sub 15}O{sub 62}{sup 9{open_quotes}} Dawson-type polyoxoanion. This crystallographic analysis, although limited by considerable disorder, represents the first solid-state structure of a Dawson-type heteropolyoxoanion-supported organometallic complex.
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- FG06-89ER13998
- OSTI ID:
- 75752
- Journal Information:
- Inorganic Chemistry, Vol. 34, Issue 4; Other Information: PBD: 15 Feb 1995
- Country of Publication:
- United States
- Language:
- English
Similar Records
Polyoxoanion-supported catalyst precursors. Synthesis and characterization of the iridium(I) and rhodium(I) precatalysts [(n-C{sub 4}H{sub 9}){sub 4}N]{sub 5}Na{sub 3}[(1,5-COD)M{center_dot}P{sub 2}W{sub 15}Nb{sub 3}O{sub 62}] (M = Ir, Rh)
The polyoxoanion-supported, atomically dispersed transition-metal precatalyst [(1,5-COD)Ir[times]P[sub 2]W[sub 15]Nb[sub 3]O[sub 62]][sup 8[minus]]: Direct [sup 17]O NMR evidence for Ir-ONb[sub 2] bonding and for a C[sub 3] average symmetry, iridium-to-polyoxoanion support