Cyclopentadienyl-Ruthenium and -Osmium Chemistry. XL. X-Ray Crystal Structures of MBr (PPh3)2(η-C5H5).CH2Cl2 (M = Ru, Os)

1995 ◽  
Vol 48 (11) ◽  
pp. 1887 ◽  
Author(s):  
MI Bruce ◽  
PJ Low ◽  
BW Skelton ◽  
ERT Tiekink ◽  
A Werth ◽  
...  

The crystal and molecular structures of MBr (PPh3)2(η-C5H5).CH2Cl2 (M = Ru and Os) have been determined. A revised synthesis of the bromo osmium complex is given. The coordination geometry about the metal atom is based on a distorted octahedron with one face being occupied by the cyclopentadienyl group [average Ru -C(Cp) 2.214(3), Os-C(Cp) 2.177(3)Ǻ] and the other by the bromide [ Ru -Br 2.5683(8), Os-Br 2.5438(9)Ǻ] and the two phosphorus atoms [ Ru -P 2.323(2), 2.329(1); Os-P 2.290(2), 2.297(2)Ǻ]. Structural parameters are compared with those of the corresponding chloro complexes and differ only minimally. Crystals of MBr (PPh3)2(η-C5H5).CH2Cl2 are triclinic, space group Pī , with unit cell dimensions ( Ru [Os]): a 14.374(5) [14.276(4)], b 14.057(4) [13.959(3)], c 10.012(5) [9.903(3)]Ǻ, α 99.43(3) [99.79(2)], β 105.60(3) [105.74(2)], γ 100.42(3) [100.39(2)]°, V 1868(1) [1817.7(9)] Ǻ3, Z 2. The structures were refined by a full-matrix least-squares procedure to R 0.050 [0.036] for 7365 [5108] reflections with I ≥ 3σ(I).


1999 ◽  
Vol 52 (10) ◽  
pp. 949 ◽  
Author(s):  
Martin A. Bennett ◽  
Glen B. Robertson ◽  
Pramesh N. Kapoor

Reaction of the cyclohexyne–platinum(0) complex [Pt(η2-C6H8)(Cy2PCH2CH2PCy2)]* with water and CO2 in the presence of triphenylphosphine gives the bicarbonate salt of the (η1-cyclohexenyl)platinum(II) cation, [Pt(η1-C6H9)(Cy2PCH2CH2 PCy2)(PPh3)] [HCO3] · 3H2O, which has been characterized by n.m.r. spectroscopy and single-crystal X-ray diffraction at low temperature. Crystals are triclinic, space group P1– with unit cell dimensions a 20.315(2), b 12.782(1), c 10.694(1) Å, α 66.61(1), β 104.73(1), γ 102.11(1)˚, and Z 2. The structure was refined to a final R value of 0.036 with use of 7553 reflections [I > 3σ(I)]. The cation has the expected, somewhat distorted planar coordination geometry; the anion consists of discrete, hydrogen-bonded dimers [(HCO3)(H2O)3]22-.



1988 ◽  
Vol 66 (12) ◽  
pp. 3176-3183 ◽  
Author(s):  
N. C. Payne ◽  
R. J. Puddephatt ◽  
R. Ravindranath ◽  
I. Treurnicht

Acetylide complexes of formula [tert-BuC≡CAu(R2PCH2PR2)], R = CH3 (6a) and C6H5 (6b), have been prepared, and characterized by spectroscopic methods. These complexes undergo a fluxional process involving a three-coordinate Au(I) centre. Complex 6a dimerizes by a first-order process in chlorinated solvents, with substitution of the acetylide ligand by chloride ion, to form [Au2(µ-dmpm)2]Cl2•2H2O (7a). The crystal and molecular structures of 7a and the iodide salt 7b have been determined by single crystal X-ray diffraction methods. Both crystallize in the triclinic space group [Formula: see text] with Z = 1; unit cell dimensions are a = 7.962(1), b = 9.987(1), c = 7.895(1) Å, α = 90.11, β = 109.13(1), and γ = 112.84(1)° for 7a; a = 8.243(1), b = 9.057(1), c = 8.167(1) Å, α = 90.23, β = 110.33(1), and γ = 89.92(1)° for 7b. The analyses refined to final agreement factors on F of R = 0.035 based on 3225 unique reflections with I > 3σ (I) for 7a, and R = 0.030 based on 2971 unique reflections with I > 3σ(I) for 7b. The structures are closely related, with the cations containing an eight-membered centrosymmetric ring formed by the Au(I) centres and the bridging dmpm ligands. The Au … Au′ distances are 3.014(1) and 3.019(1) Å in 7a and 7b, respectively. In the solid state, the halide ions bridge the two Au centres, and, together with the water molecules, form a network of hydrogen bonds running at an angle of 104° to the eight-membered Au2P4C2 rings.



1989 ◽  
Vol 42 (5) ◽  
pp. 741 ◽  
Author(s):  
MI Bruce ◽  
ERT Tiekink

The crystal and molecular structures of the title compound, C12F10N2.C18H22H2,are reported. The crystal structure is comprised of stacks of alternate decafluoroazobenzene and azomesitylene molecules with the vertical separation between successive molecules being approximately 3.42 � . The stacks are aligned so that the azobenzene molecules of one stack are adjacent to the azomesitylene molecules of the neighbouring stacks; there are no significant intercolumn contacts. Crystals are monoclinic, space group P21/n with unit cell dimensions a 7.197(2), b 15.432(3), c 12.513(3) � , β 96.33(2)� , and Z 2. The structure was refined by a full-matrix least-squares procedure to final R 0.059 for 915 reflections for which 1 ≥ 3.O σ(I).



1993 ◽  
Vol 46 (4) ◽  
pp. 561 ◽  
Author(s):  
VJ Hall ◽  
G Siasios ◽  
ERT Tiekink

The title compounds, R3PAuSC(= NPh )OR′, R = Et, Ph or Cy and R′ = Me, Et, Pr, Pri or Cy, have been prepared and characterized by spectroscopic methods ( i.r., 1H and 13C n.m.r. and f.a.b . m.s .) and, in the case of the R = Ph and R′ = Me compound, by single-crystal X-ray diffraction methods. The spectroscopic data are consistent with the R3PAu moiety being coordinated by the sulfur atom of the thiolate ligand. This has been confirmed by an X-ray study on Ph3PAuSC(= NPh )OMe which shows the gold atom to be linearly coordinated by the phosphorus and sulfur atoms; Au-P(1) 2.258(1), Au-S(1) 2.301(1) Ǻ and P-Au-S 177.7(1)°. Crystals of Ph3PAuSC(= NPh ) OMe are triclinic, space group pī, with unit cell dimensions: a 10.825(1), b 12.553(2), c 8.914(2) Ǻ, α 97.86(2), β 93.79(1), γ 88.60(1)°, V 1197.1 Ǻ3, Z 2. The structure was refined by a full-matrix least-squares procedure to R 0.028 for 4409 reflections with I ≥ 2.5σ(I).



1980 ◽  
Vol 33 (11) ◽  
pp. 2369 ◽  
Author(s):  
E Horn ◽  
MR Snow

The complexes Re(CO)5ClO4, Re(CO)5PO2F2, L2(CO)3Re(OClO3) and L2(CO)3Re(PO2F2), where L2 = 2,2?-bipyridyl (bpy), have been synthesized by bromide abstraction reactions from the respective rhenium carbonyl bromide precursors. The complexes were characterized by infrared and mass spectroscopy. The crystal structure of (bpy)(CO)3Re(PO2F2) has been determined from X-ray diffraction data by the heavy-atom technique. The crystals are triclinic, space group Pī with a 8.620(3), b 15.912(5), c 6.466(3) Ǻ, α 102.08(8), β 83.29(8), γ 95.08(4) and Z 2. The structure has been refined by full-matrix least-squares from 2829 reflections to R = 0.084, Rw = 0.088. The coordination geometry about rhenium is that of a distorted octahedron. Difluorophosphate coordinates to the metal centre by one of its oxygen atoms. Formation of the difluorophosphate by hydrolysis of hexafluorophosphate was shown by 31P n.m.r. spectra.



1990 ◽  
Vol 45 (10) ◽  
pp. 1369-1382 ◽  
Author(s):  
Heindirk tom Dieck ◽  
Lutz Stamp

Diazadienes RN = CR′-CR′ = NR (DAD) form molecular complexes with copper(I) halides of composition (DAD)CuX, the structures of which vary from [(DAD)2Cu]+(CuCl2)⁻ with a non-tetrahedral bis(chelated) cation, over [(DAD)CuCl]2 with asymmetrically bridging chloro ligands to planar three-coordinate (DAD)CuCl. The composition of the isolated complexes depends on the relative concentrations or on the solvent. The “soft” coordination geometry of copper is underlined by the structure of the coordination polymer of composition (DAD)2Cu5Cl5, in which Cu atoms of coordination number 2, 3 and 4 and very irregular geometries are encountered and where the DAD ligands are exclusively bridging. Halide ions and sp2-nitrogen donors are very competitive. Bridging DAD ligands are also encountered in (DAD)Cu-Y with the less nucleophilic anions trifluoromethane-sulphonate or perchlorate. Crystal and molecular structures are established for all these coordination geometries and the causes are discussed for the coordination flexibility of copper(I)



1992 ◽  
Vol 45 (11) ◽  
pp. 1933 ◽  
Author(s):  
PR Traill ◽  
AG Wedd ◽  
ERT Tiekink

The characterization of two MoVI complexes, cis -[MoO2(2-pymS)2] and cis -[MoO2(2-pyS)2] (where 2-pymSH is pyrimidine-2-thiol and 2-pySH is pyridine-2-thiol), and their reaction with Ph3P are reported. The X-ray structure of cis -[MoO2(2-pymS)2] shows the molybdenum atom to exist in a distorted octahedral geometry defined by two mutually cis oxygen atoms and two chelating 2-pymS ligands so that the two sulfur atoms occupy approximate trans positions. Crystals of cis -[MoO2(2-pymS)2] are monoclinic, space group P 21/n, with unit cell dimensions: a 9.301(3), b 12.121(2), c 11.303(3) �, β 112.62(3)�, V 1176.3 �3, Z 4. The structure was refined by a full-matrix least-squares procedure to R 0.067 for 1858 reflections with I ≥ 2.5 (I).



1975 ◽  
Vol 53 (18) ◽  
pp. 2707-2713 ◽  
Author(s):  
Debbie Allen ◽  
Colin James Lyne Lock ◽  
Graham Turner ◽  
John Powell

The crystal and molecular structures of pentane-2,4-dionato-(2,3,5,6-tetrahapto-2,3-dicarbomethoxo[2.2.1]bicycloheptadienerhodium(I), Rh(C5H7O2)(C7H6(CO2CH3)2), have been measured by single crystal X-ray diffraction. The orange crystals are monoclinic, space group P21/c, Z = 4, a = 9.245(4), b = 9.003(4), c = 21.680(15) Å, β = 113.41(5)°. The calculated and observed densities are 1.645 and 1.642(5) respectively. Intensity data were collected on a Syntex [Formula: see text] diffractometer and a full matrix least squares refinement on 3010 observed reflections leads to a conventional R = 0.0660. The structure can be considered as a roughly square planar arrangement of ligands around the rhodium atom composed of two β-ketoenolate oxygen atoms (Rh—O, 2.037(5) and 2.025(5) Å ) and the centers of the two ethylenic groups. The Rh—C distances for the olefin group attached to the two carbomethoxo groups, 2.117(8), 2.108(8) Å, appear to be slightly larger than those for the other olefinic group, 2.087(7), 2.082(6), and the corresponding C=C distances of 1.375(10) and 1.410(9) Å are different at the 95% confidence level.



1986 ◽  
Vol 39 (12) ◽  
pp. 2145 ◽  
Author(s):  
MI Bruce ◽  
MR Snow ◽  
ERT Tiekink

The crystal structure of OsPt2(μ-CO)3(CO)2(PPh3)3 has been determined by single-crystal X-ray diffraction techniques. Crystals are triclinic, space group Pī with unit cell dimensions a 13.593(4), b 15.839(4), c 12.633(8) Ǻ, α 102.97(3), β 108.18(2), γ 84.86(3)° with Z2. The structure was refined by a full-matrix least-squares procedure on 5896 reflections [I ≥ 2.5σ(I)] to final R 0.028 and Rw 0.034. A triphenylphosphine ligand binds each of the metal atoms disposed at the corners of a triangle. Each metal-metal bond is spanned by a bridging carbonyl group. The coordination about the osmium atom is completed by two terminal carbonyl groups.



1997 ◽  
Vol 53 (5) ◽  
pp. 787-794 ◽  
Author(s):  
A. E. Cohen ◽  
B. M. Craven ◽  
W. T. Klooster

Spermine phosphate hexahydrate crystallizes in space group P21/a with unit-cell dimensions a = 7.931 (1), b = 23.158 (5), c = 6.856 (2) Å, and \beta = 113.44 (2)° at 125 K with unit-cell contents [(C10H30N4)^{4+}_{2} (HPO4)^{2-}_{4}.12H2O]. The packing of spermines and monohydrogen phosphates in this crystal structure has features which may be relevant to the binding of spermine to DNA. Another important structural feature is the presence of channels containing water that is hydrogen bonded as in ice-Ih with disordered protons. The channels occur between sheets of spermine long chains and are also bordered by hydrogen-bonded monohydrogen phosphate chains. The hydrogen-bonding scheme of these water chains proposed on the basis of an earlier X-ray study is now confirmed. Nuclear positions, anisotropic mean-square (m.s.) displacements, an overall scale factor and two extinction parameters (\rho and g) were refined using full-matrix least-squares giving values of R(F^{2}_{o}) = 0.09, Rw(F^{2}_{o}) = 0.11 and S = 1.02. Thermal vibrational analysis revealed that the backbone of the spermine cation can be described as a single rigid segment with a substantial libration of 27 deg2 around the spermine molecular long axis.



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