518344-52-0Relevant academic research and scientific papers
Unsymmetrical complexes containing the linear tetraphosphine ligand DPPEPM
Nair, Padma,White, Colin P.,Anderson, Gordon K.,Rath, Nigam P.
, p. 529 - 537 (2007/10/03)
The tetraphosphine DPPEPM reacts with [PtMe2(cod)] to produce [PtMe2(DPPEPM-PP)] (1) in near quantitative yield. On standing in solution, the free P atoms become oxidized to give [PtMe2(DPPEPM(O) 2-PP)] (1a), which has been characterized by X-ray crystallography. In contrast, reactions of DPPEPM with [MCl2(cod)] (M = Pd, Pt) yield ionic products of the form [M(DPPEPM-PP)2]MCl4 (3, 4). When a solution of the platinum complex was allowed to stand, crystals of [Pt(μ-Cl)(μ-DPPEPM)2]Cl3 (5) were obtained. In a third set of reactions, treatment of [PtClR(cod)] (R = Me, Ph) or [PdClMe(cod)] with DPPEPM gives species of the type [MR(DPPEPM-PPP)]Cl (6-8), in which one of the internal P atoms is uncoordinated. Reactions of [PtR2(DPPEPM-PP)] with [PtR2′(cod)] or [MCl2(cod)] (M = Pd, Pt), or of [PtR(DPPEPM-PPP)]Cl with [MCl2(cod)], lead to unsymmetrical bimetallic complexes. [PtMe2(μ-DPPEPM)PdCl2] (11) and [PtClPh(μ-DPPEPM)PdCl2] (14) have been characterized crystallographically. Trimetallic complexes of the form [{PtR 2(μ-DPPEPM)}2M][MCl4] (M = Pd, Pt, 15-17) are produced by reaction of [PtR2(DPPEPM-PP)] with [MCl 2(cod)].
Palladium and platinum complexes containing the linear tetraphosphine bis[((diphenylphosphino)ethyl)phenylphosphino]methane
Nair, Padma,Anderson, Gordon K.,Rath, Nigam P.
, p. 1494 - 1502 (2008/10/08)
The linear tetraphosphine bis [((diphenylphosphino)ethyl)phenylphosphino] methane (DPPEPM) has been prepared and separated into its meso and racemic forms. Each has been reacted with elemental sulfur, and the structure of the meso compound DPPEPM-S4 has been determined crystallographically. The meso or racemic form of DPPEPM reacts with 2 equiv of [MCl2(cod)] (M = Pd, Pt) or [PtR2(cod)] (R = Me, Ph, CH2Ph, C6H4Me-4) to give complexes of the form [M2X4(μ-DPPEPM)], in which DPPEPM acts as both a chelating and a bridging ligand. Complexes containing additional chloride bridges, [M2R2(μ-Cl)(μDPPEPM)]PF6, have been prepared from DPPEPM and [PtClR(cod)] (R = Me, Ph, CH2Ph), [PdClR(cod)] (R = Me, CH2Ph), or [Pd2R2(μ-Cl)2(AsPh3)2] (R = Ph, COMe), followed by TlPF6. Chloride-bridged compounds could also be prepared by treatment of [M2Cl4(μ-DPPEPM)] with 1 equiv of TlPF6. Addition of Bu4NI to [M2Me2(μ-Cl)(μ-DPPEPM)]PF6 resulted in bridge opening, and further treatment with TlPF6 gave the corresponding iodide-bridged species. The compounds have been characterized by NMR spectroscopy and by elemental analysis or high-resolution mass spectrometry. The solid-state structures of [Pd2Cl4(μ-DPPEPM)] and [Pt2Ph4(μ-DPPEPM)] are also reported.
