@article {1059, title = {Homoleptic, sigma-bonded octahedral [M(CO)(6)](2+) cations of iron(II), ruthenium(II), and osmium(II): Part 1: Syntheses, thermochemical and vibrational characterizations, and molecular structures as [Sb2F11](-) and [SbF6](-) salts. A comprehensive, compa}, journal = {Inorganic Chemistry}, volume = {44}, number = {12}, year = {2005}, note = {ISI Document Delivery No.: 934LPTimes Cited: 5Cited Reference Count: 100}, month = {Jun}, pages = {4189-4205}, type = {Article}, abstract = {Homoleptic octahedral, superelectrophilic sigma-bonded metal carbonyl cations of the type [M(CO)(6)](2+) (M = Ru, Os) are generated in the Bronsted-Lewis conjugate superacid HF/SbF5 by reductive carbonylation Of M(SO3F)(3) (M = Ru, Os) or OsF6. Thermally stable salts form with either [Sb2F11](-) or [SbF6](-) as anion, just as for the previously reported [Fe(CO)(6)](2+) cation. The latter salts are generated by oxidative (XeF2) carbonylation of Fe(CO)(5) in HF/ SbF5. A rationale for the two diverging synthetic approaches is provided. The thermal stabilities Of [M(CO)(6)][SbF6](2) salts, studied by DSC, range from 180 degrees C for M = Fe to 350 degrees C for M = Os before decarbonylation occurs. The two triads [M(CO)(6)][SbF6](2) and [M(CO)(6)][Sb2F11](2) (M = Fe, Ru, Os) are extensively characterized by single-crystal X-ray diffraction and vibrational and C-13 NMR spectroscopy, aided by computational studies of the cations. The three [M(CO)(6)][SbF6](2) salts (M = Fe, Ru, Os) crystallize in the tetragonal space group P4/mnc (No. 128), whereas the corresponding [Sb2F11](-) salts are monoclinic, crystallizing in space group P2(1)/n (No. 14). In both triads, the unit cell parameters are nearly invariant of the metal. Bond parameters for the anions [SbF6](-) and [Sb2F11](-) and their vibrational properties in the two triads are completely identical. In all six salts, the structural and vibrational properties of the [M(CO)(6)](2+) cations (M = Fe, Ru, Os) are independent of the counteranion and for the most part independent of M and nearly identical. Interionic C center dot center dot center dot F contacts are similarly weak in all six salts. Metal dependency is noted only in the C-13 NMR spectra, in the skeletal M-C vibrations, and to a much smaller extent in some of the C-O stretching fundamentals (A(1g) and T-1u). The findings reported here are unprecedented among metal carbonyl cations and their salts.}, keywords = {ANTIMONY PENTAFLUORIDE, CRYSTAL-STRUCTURE, ELECTRON-DIFFRACTION, HEXAKIS(CARBONYL)IRON(II), INFRARED SPECTRA, MAS-NMR-SPECTRA, METAL-CARBONYL CATIONS, PHASE, SOLVENT SYSTEM, SUPERACID MEDIA, UNDECAFLUORODIANTIMONATE(V), WEAKLY COORDINATING ANIONS}, isbn = {0020-1669}, url = {://000229710600021}, author = {Bernhardt, E. and Bach, C. and Bley, B. and Wartchow, R. and Westphal, U. and Sham, I. H. T. and von Ahsen, B. and Wang, C. Q. and Willner, H. and Thompson, R. C. and Aubke, F.} } @article {1059, title = {Homoleptic, sigma-bonded octahedral [M(CO)(6)](2+) cations of iron(II), ruthenium(II), and osmium(II): Part 1: Syntheses, thermochemical and vibrational characterizations, and molecular structures as [Sb2F11](-) and [SbF6](-) salts. A comprehensive, compa}, journal = {Inorganic Chemistry}, volume = {44}, number = {12}, year = {2005}, note = {ISI Document Delivery No.: 934LPTimes Cited: 5Cited Reference Count: 100}, month = {Jun}, pages = {4189-4205}, type = {Article}, abstract = {Homoleptic octahedral, superelectrophilic sigma-bonded metal carbonyl cations of the type [M(CO)(6)](2+) (M = Ru, Os) are generated in the Bronsted-Lewis conjugate superacid HF/SbF5 by reductive carbonylation Of M(SO3F)(3) (M = Ru, Os) or OsF6. Thermally stable salts form with either [Sb2F11](-) or [SbF6](-) as anion, just as for the previously reported [Fe(CO)(6)](2+) cation. The latter salts are generated by oxidative (XeF2) carbonylation of Fe(CO)(5) in HF/ SbF5. A rationale for the two diverging synthetic approaches is provided. The thermal stabilities Of [M(CO)(6)][SbF6](2) salts, studied by DSC, range from 180 degrees C for M = Fe to 350 degrees C for M = Os before decarbonylation occurs. The two triads [M(CO)(6)][SbF6](2) and [M(CO)(6)][Sb2F11](2) (M = Fe, Ru, Os) are extensively characterized by single-crystal X-ray diffraction and vibrational and C-13 NMR spectroscopy, aided by computational studies of the cations. The three [M(CO)(6)][SbF6](2) salts (M = Fe, Ru, Os) crystallize in the tetragonal space group P4/mnc (No. 128), whereas the corresponding [Sb2F11](-) salts are monoclinic, crystallizing in space group P2(1)/n (No. 14). In both triads, the unit cell parameters are nearly invariant of the metal. Bond parameters for the anions [SbF6](-) and [Sb2F11](-) and their vibrational properties in the two triads are completely identical. In all six salts, the structural and vibrational properties of the [M(CO)(6)](2+) cations (M = Fe, Ru, Os) are independent of the counteranion and for the most part independent of M and nearly identical. Interionic C center dot center dot center dot F contacts are similarly weak in all six salts. Metal dependency is noted only in the C-13 NMR spectra, in the skeletal M-C vibrations, and to a much smaller extent in some of the C-O stretching fundamentals (A(1g) and T-1u). The findings reported here are unprecedented among metal carbonyl cations and their salts.}, keywords = {ANTIMONY PENTAFLUORIDE, CRYSTAL-STRUCTURE, ELECTRON-DIFFRACTION, HEXAKIS(CARBONYL)IRON(II), INFRARED SPECTRA, MAS-NMR-SPECTRA, METAL-CARBONYL CATIONS, PHASE, SOLVENT SYSTEM, SUPERACID MEDIA, UNDECAFLUORODIANTIMONATE(V), WEAKLY COORDINATING ANIONS}, isbn = {0020-1669}, url = {://000229710600021}, author = {Bernhardt, E. and Bach, C. and Bley, B. and Wartchow, R. and Westphal, U. and Sham, I. H. T. and von Ahsen, B. and Wang, C. Q. and Willner, H. and Thompson, R. C. and Aubke, F.} } @article {536, title = {The synthesis, vibrational spectra, and molecular structure of [Ir(CO)(6)][SbF6](3)center dot 4HF - The first structurally characterized salt with a tripositive, homoleptic metal carbonyl cation and the first example of a tetrahedral hydrogen-bonded (HF)(}, journal = {Journal of the American Chemical Society}, volume = {124}, number = {28}, year = {2002}, note = {ISI Document Delivery No.: 573QWTimes Cited: 14Cited Reference Count: 58}, month = {Jul}, pages = {8371-8379}, type = {Article}, abstract = {{The reductive carbonylation of IrF6 in a dilute solution of SbF5 in anhydrous HF (1:6 by volume) produces surprisingly at 25 degreesC and 1.5 atm CO the complex salt [Ir(CO)(6)][SbF6](3).4HF, while [Ir(CO)(6)][Sb2F11](3) is obtained in liquid SbF5 under similar conditions. Vibrational spectra in the CO stretching range for both salts and [Ir(CO)(6)](3+)((solv)) are identical within error limits, and v(CO)(av) is with 2269 cm(-1) the highest average stretching frequency so far observed for octahedral metal carbonyl cations. A vibrational assignment supported by DFT calculations is presented, and the vibrational fundamentals are compared to those of [OS(CO)(6)](2+). The molecular structure of [Ir(CO)(6)][SbF6](3).4HF is determined by single-crystal X-ray diffraction. Crystal data for [Ir(CO)(6)][SbF6](3).4HF: rhombohedral, R3c (No. 161)}, keywords = {(3+), CARBOCATIONS, CHEMISTRY, CRYSTAL-STRUCTURES, IR, MO, OS, RU, SUPERACID MEDIA, UNDECAFLUORODIANTIMONATE(V)}, isbn = {0002-7863}, url = {://000176843200032}, author = {von Ahsen, B. and Berkei, M. and Henkel, G. and Willner, H. and Aubke, F.} }