Synthesis of homo- or hetero-trinuclear palladium(II)/platinum(II) compounds with bridging phosphido ligands. Crystal and electronic structures (DFT) of [N(PPh3)2]2[Pt3(μ-PPh2)4(C6F5)4] and of its oxidation product[Pt3(C6F5)4(μ-PPh2)4]

The synthesis of the trinuclear phosphido complexes [NBu4]2[(C6F5)2M(μ-PPh2)2M‘(μ-PPh2)2M‘ ‘(C6F5)2] (M, M‘, M‘ ‘ = Pd(II), Pt(II), 1−5) is described. A study of the electrochemical behavior of these complexes is reported. The chemical oxidation of the homonuclear platinum derivative involving two electrons yields the complex [(C6F5)2Pt(μ-PPh2)2Pt(μ-PPh2)2Pt(C6F5)2] (6), which contains Pt in average formal oxidation state 2.67. The structure of the complexes has been established by spectroscopic means, and X-ray diffraction studies have been carried out on 1 and 6. Quantum chemical calculations at the B3LYP level of theory, using the LANL2DZ basis set, provide a satisfactory description of the structural, bonding, energetic, and electronic properties of these phosphido-bridged trinuclear M3(II) compounds modeled as [(CF3)2M(μ-PH2)2M‘(μ-PH2)2M‘ ‘(CF3)2]2- (M, M‘, M‘ ‘ = Pd(II), Pt(II), 1M−5M) and the oxidation product [Pt3(μ-PH2)4(CF3)4] (6M).