Synthesis and characterization of binuclear Pt(IV) complexes and tetranuclear mixed valence complexes of Platinum(II)-Platinum(IV)

Publication date: Available online 29 June 2019Source: Journal of Organometallic ChemistryAuthor(s): José M. Casas, Beatriz E. Diosdado, Juan Forniés, M. Ángeles García-Monforte, Raquel Laporta, Antonio Martín, Milagros TomásAbstractThe binuclear platinum(IV) complexes [NBu4]2[PtIV2(μ-Cl)2(C6F5)4Cl4] (2) and [PtIV2(μ-C8H6N4)2(C6F5)4Cl4] (4) have been synthesized by oxidative addition of chlorine to the binuclear platinum(II) species, but [NBu4]2[PtIV2(μ-OH)2(C6F5)4Cl4] (3) has been synthesized by substitution of the chloride bridges of the platinum(IV) complex. The square planar platinum environments of the Pt(II) starting materials change, as expected, to Pt(IV) octahedral environments with the chloride ligands in trans-position. Only minor changes in the Pt-X (X = Clbridge, OH) interatomic distances are produced because of the oxidation.Depending on the size of the bridging ligands and also probably the anionic character of the diplatinum(IV) complexes, the apical chloride ligands can still act as bridges toward other Pt centres. Thus, the organometallic tetra-nuclear mixed-valence platinum(IV)-platinum(II) complexes with formulas [NBu4]2[{PtIV(μ-X)(C6F5)2}2(μ-Cl)4{PtII(C6F5)2}2] [X = Cl (5), OH (6)] were obtained by reaction of 2 and 3 with cis-[PtII(C6F5)2(thf)2]. The structures of complexes 2, 4 and 6 have been determined by single-crystal X-ray diffraction studies. These crystal structures confirm that the oxidative addition of the chlorine molecule t...
Source: Journal of Organometallic Chemistry - Category: Chemistry Source Type: research