102781-92-0Relevant academic research and scientific papers
Mixed carbonyl-nitrile complexes of dirhenium(II). the structural characterization and reactivity of salts of the [Re2Cl3(μ-dPPm)2(CO)(NCMe)n] + cations (dppm = Ph2PCH2PPh2, n = 1 or 2)
Chantler, James,Fanwick, Phillip E.,Walton, Richard A.
, p. 219 - 228 (2007/10/03)
The monocarbonyl complexes Re2X4(μ-dppm)2(CO) (X = Cl or Br) react with stoichiometric quantities of the nitriles RCN (R = Me or Ph) in the presence of TlY (Y = PF6 or O3SCF3) to afford complexes of the type [Re2X3(μ-dppm)2(CO)(NCR)]Y and [Re2X3(μ-dppm)2(CO)(NCR)2]Y in high yield. Crystal structure determinations on the salts [Re2Cl3(μ-dppm)2(CO)(NCMe)]O 3SCF3 and [Re2Cl3(μ-dppm)2(CO)(NCMe) 2]ReO4 have shown that the former has the unsymmetrical structure [(MeCN)(CO)ClRe(μ-dppm)2ReCl2]+ with a Re≡Re bond (Re-Re distance 2.2881(7) A?), while the bis-nitrile complex is the edge-sharing bioctahedron [(MeCN)ClRe(μ-Cl)(μ-CO)(μ-dppm)2ReCl(NCMe)]+, with an all-cis arrangement of the μ-CO and two MeCN ligands and a Re=Re bond (Re-Re distance 2.5669(4) A?). The species [Re2X3(μ-dppm)2(CO)(NCMe)]+ and [Re2X3(μ-dppm)2(CO)(NCMe)2] + readily interconvert upon the addition or loss of an acetonitrile ligand and, along with their benzonitrile analogues, they react with halide, XylNC and acetylene to afford Re2X4(μ-dppm)2(CO), [Re2X3(μ-dppm)2(CO)(CNXyl)2]Y and [Re2X3(μ-dppm)2(CO)(η2-C 2H2)]Y, respectively.
Mixed Carbonyl-Isocyanide and Carbonyl-Nitrile Complexes Derived from the Reactions of the Multiply Bonded Dirhenium(II) Complexes Re2X4(dppm)2(CO) (X=Cl or Br; dppm=Ph2PCH2PPh2). The Structural Characterization of Cl2Re(μ-dppm)2ReCl(CO) and Cl2Re(μ-Cl)(μ-CO)(μ-dppm)2ReCl(CNxylyl)
Cotton, F. Albert,Dunbar, Kim R.,Price, Andrew C.,Schwotzer, Willi,Walton, Richard A.
, p. 4843 - 4850 (2007/10/02)
Reactions of the triply bonded dirhenium(II) complexes Re2X4(dppm)2 (X=Cl or Br; dppm=bis(diphenylphosphino)methane) with carbon monoxide yielded the monocarbonyls X2Re(μ-X)(μ-dppm)2ReX(CO).The chloride derivative Re2Cl4(dppm)2(CO) (1), which has been characterized by X-ray diffraction, cocrystallizes with three independent benzene molecules in the hexagonal space group P63/m (No. 176).The cell dimensions are a=28.469(4) Angstroem, c=14.301(2) Angstroem, V=10037(4) Angstroem3, and Z=6.The Re-Re bond distance is 2.338(1) Angstroem and the molecule has a novel A-frame-like structure.The crystal structure was refined to R=0.048 (unit weights).Reactions of this molecule with 1 equiv of an isocyanide (RNC) generate complexes of stoichiometry Re2Cl4(dppm)2(CO)(CNR) (R=i-Pr, t-Bu, xylyl, or mesityl) in which the CO ligand is in either a terminal or bridging position, depending on the isocyanide used.The xylylNC derivative Cl2Re(μ-Cl)(μ-CO)(μ-dppm)2ReCl(CNxylyl) (2) has been characterized by X-ray crystallography.Compound 2 crystallizes in the monoclinic system, space group P21/n, with a=18.211(4) Angstroem, b=15.907(2) Angstroem, c=20.887(6) Angstroem, β=93.63(3) deg, V=6048(1) Angstroem3, and Z=4.The crystal structure was refined to residuals of R=0.0650, Rw=0.0691.The Re-Re bond distance is 2.581(2) Angstroem, and the molecule comprises a pair of distorted, edge-sharing octahedra.The monocarbonyl reacts readily with an excess of nitrile R'CN in the presence of TlPF6 to yielded the PF6- salts of stoichiometry PF6 (R'=CH3, C2H5, or C6H5).The IR and NMR (1H and 31P) spectral properties of these particular complexes suggest that there is an all-cis arrangement of chloride ligands on one side of the molecule.
