Uncommon Solvent Effect in Oxidative Addition of MeI to a New Dinuclear Platinum Complex Containing a Platina(II)cyclopentane Moiety

Self-Assembly of a Hierarchical Metal-Organic Framework at the Liquid/Liquid Interface via π-π Stacking Manipulations in Organoplatinum(IV) Complexes for Methanol Fuel Cells

This study focuses on the facile synthesis of the hierarchical architecture of zeolitic imidazolate framework-8 (ZIF-8) films containing an ultrasmall amount of Pt(0) by investigating the synthesis of different organoplatinum complexes and manipulating the π-π stacking effect in these complexes at the liquid/liquid interface. The organometallic Pt(IV) precursors were complexes with a formula of [PtXMe2(R)(bpy)] (bpy = 2,2'-bipyridine; for complex 2, R = CH2CH═CHC6H5 and X = Br; for complex 3, R = CH2CH═CH2 and X = Br; for complex 4, R = Me and X = I) prepared by oxidative addition of cinnamyl bromide, allyl bromide, or methyl iodide to [PtMe2(bpy)] (complex 1). Different thin films were synthesized starting from three organometallic Pt(IV) precursors (i) by reduction of the Pt complexes at the toluene/water interface (TF2-TF4), (ii) by encapsulation of the Pt precursors in a ZIF-8 (TF5-TF7), and (iii) by reduction of the Pt precursors onto a ZIF-8 (TF8-TF10). The self-assembly of ZIF-8 and different organoplatinum precursors at the interface of two immiscible liquids leads to the preparation of films with well-engineered structures such as rhombic dodecahedra, nanorods, hierarchical architectures, and nanowires, which are very difficult and complicated to synthesize under normal conditions. The ultralow loading of platinum complexes with different degrees of π-π stacking of dangling moieties has a great impact on the structure and morphology (directing agent), which in turn drastically changes the catalytic properties. The obtained films were applied as electrocatalysts for methanol oxidation in fuel cells. The electrocatalytic performance of organoplatinum containing a cinnamyl group in hierarchical architecture TF8 was found to be superior to those of nonhierarchical structures.

Homo and heterobimetallic palladium and platinum complexes bearing μ-diphosphane bridges involved in biological studies

Given the increasing reports of well-defined bimetallic molecular complexes as potential anticancer agents in the last decades, along with the prevalence of platinum in anticancer therapy, we report here a detailed survey of bimetallic platinum and palladium complexes investigated as potential anticancer agents. Specifically, we will concentrate on the synthesis, characterisation and biological (anticancer) studies of a sub-class of these agents, namely homo and heterobimetallic complexes bearing a bridging phosphane ligand of the type: [L_nM₁(μ-R₂P(CH₂)_nPR₂)M₂L_m] (where M₁ is platinum or palladium, M₂ is any other transition metal, R = alkyl or aryl substituents, L_n or L_m are co-ligands, n = 1-6). We will review the in vitro and in vivo activities and any mechanistic anticancer studies of these complexes with a view of trying to delineate patterns in biological activity and structure-activity relationships (SAR). We do not include the review of bimetallic complexes in this class that have not undergone any anticancer testing, nor those that have been involved in other biological investigations unrelated to cancer studies.

Photophysical study on unsymmetrical binuclear cycloplatinated(ii) complexes

A general synthetic method has been designed to prepare a new series of unsymmetrical binuclear cyclometalated organoplatinum(ii) complexes and the effect of each part on their luminescence properties were investigated.

Oxidative addition reaction of diarylplatinum(II) complexes with MeI in ionic liquid media: a kinetic study

A kinetic study of the oxidative addition reaction of diarylplatinum(II) complexes [Pt(p-MeC(6)H(4))(2)(NN)] (1a: NN = 1,10-phenanthroline (phen) and 1b: NN = 4,4'-di-tert-butyl-2,2'-bipyridine ((t)Bu(2)bpy)) with MeI in ionic liquids 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([bmim][bta]) or 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF(4)]) is described. The reactions were investigated as a function of MeI concentration and temperature under pseudo-first-order conditions using UV-vis spectroscopy techniques. In general, the oxidative addition reactions in ionic liquids followed an S(N)2 mechanism, similar to that reported for the related reactions in conventional solvents, e.g. benzene or acetone. The reaction rates in different solvents followed the order acetone > ionic liquids > benzene. The trend in the values of k(2) clearly indicated that ionic liquids behave like conventional solvents and that no particular 'ionic liquid effect' was detected in this kind of reaction. The effect of solvent on the reactions was examined using a linear solvation energy relationship (LSER) based on the Kamlet-Taft solvent scale. The activation parameters, DeltaH(++) and DeltaS(++), were obtained for the reactions in each solvent and the investigation of enthalpy-entropy compensation confirmed that the mechanism operated in all solvents is similar.