82822-31-9Relevant articles and documents
Synthesis and characterisation of 2,2-bis(hydroxymethyl)-1,3-diselenolato metal(II) complexes bearing various phosphanes
Niksch, Tobias,Goerls, Helmar,Friedrich, Manfred,Oilunkaniemi, Raija,Laitinen, Risto,Weigand, Wolfgang
, p. 74 - 94 (2010/04/01)
An improved synthesis of 4,4-bis(hydroxymethyl)-1,2-diselenolane and the complexation properties of the corresponding diselenolato dianion to group-10 metals are reported. We describe an efficient and straightforward procedure that bypasses the isolation of the malodorous and airsensitive diselenol and starts with the diselenide appropriate group-10 metal complex bearing phosphane and chlorido ligands. A series of complexes with various monoand bidentate phosphanes is prepared and characterised by multinuclear NMR spectroscopy, mass spectrometry, and elemental analysis. Furthermore, the structure of most complexes is studied by single-crystal X-ray diffraction to establish their supramolecular arrangement in the solid state. Consequently, several group-10 metal complexes with P-M-P angles (bite angles) in the range from 71-108° are investigated. The use of the sterically demanding bridging phosphane 4,5-bis(diphenylphosphanyl)-9,9-dimethylxanthene, which exhibits a large bite angle yields a mixture of a di- and trinuclear complex. While the platinum-containing complexes are proven to be rather stable, the palladium and nickel analogues tend to decompose. Especially, the nickel complexes were found to be sensitive against: oxidation. This circumstance leads to the formation of the so far unknown 1,8-bis(diphenylphosphanyl)naphthalene monooxide, the formation and structure of which could be confirmed from NMR spectroscopic data and single-crystal X-ray diffraction.
Synthesis spectroscopic and structural properties of transition metal complexes of the o-xylyl diphosphine o-C6H4(CH 2PPh2)2
Brown, Michael D.,Levason, William,Reid, Gillian,Watts, Rebecca
, p. 75 - 87 (2008/10/09)
The systematic coordination chemistry of the wide-angle diphosphine o-C6H4(CH2PPh2)2 (L 1) has been investigated with metal ions from Groups 9-11 in order to explore the consequences of the steric demands of the phosphine and its flexibility towards different oxidation states and coordination geometries. The products isolated include the tetrahedral [CoX2(L1)] (X = Cl, Br or I), the very distorted square planar [Rh(L1) 2]+, [M(cod)(L1)]+ (M = Rh or Ir), square planar [NiX2(L1)] (X = Cl or Br), [M′Cl 2(L1)] (M′ = Pd or Pt), the chloro-bridged [Pd 2Cl2(L1)2]2+, [Pd(L 1)2]2+, the tetrahedral [M″(L 1)2]+ (M″ = Cu, Ag or Au) and the dinuclear [(AuCl)2(L1)]. Chemical oxidation of some of the complexes are described, giving examples of Co(III), Ni(III) and Pt(IV) species. Where possible the products have been characterised by IR, UV-vis, NMR (1H, 31P, 63Cu and 195Pt as appropriate) spectroscopies, mass spectrometry and microanalysis. Crystal structures of six representative examples confirm the coordination environments in particular species and illustrate the steric demands of L1. L 1 is a versatile ligand which can readily alter its chelate bite angle to accommodate a range of coordination geometries (the P?P distances within the chelate rings varies by >0.5 ?), and the presence of the rigid aromatic ring in the C4 backbone leads to some preorganisation favouring cis chelation. It also shows a preference for low coordination numbers and this results in some unexpected products.