Platinum complexes having redox-active PPh2CCFc and/or CCFc as terminal or bridging ligands

Abstract

A series of heteronuclear-Pt(ii) complexes containing ferrocenylethynyl units linked directly (Pt-C[triple bond]CFc) or through a phosphorous atom (Pt-PPh(2)C[triple bond]CFc) to the platinum center is reported. The reaction of derivative [cis-Pt(R(F))(2)(PPh(2)C[triple bond]CFc)(2)] (R(F) = C(6)F(5)) with the solvate complex [cis-Pt(R(F))(2)(thf)(2)] leads to the formation of an asymmetrical heteronuclear diplatinum complex [{Pt(R(F))(2)(mu-1kappaP:2eta(2)-PPh(2)C[triple bond]CFc)(2)}Pt(R(F))(2)] having the "cis-Pt(R(F))(2)" fragment coordinated to the triple bonds of both ferrocenylethynylphosphine units, while treatment of [cis-Pt(C[triple bond]CFc)(2)(PPh(2)C[triple bond]CR)(2)] (R = Fc , Ph , tBu ) with the same solvate [cis-Pt(R(F))(2)(thf)(2)], affords double ferrocenylacetylide-bridged diplatinum systems [{Pt(PPh(2)C[triple bond]CR)(2)(mu-eta(1):eta(2)-C[triple bond]CFc)(2)}Pt(R(F))(2)] . The solid-state structures of [cis/trans-Pt(R(F))(2)(PPh(2)C[triple bond]CFc)(2)] /, [cis-Pt(R(F))(2)(PPh(2)C[triple bond]CFc)(tht)] (tht = tetrahydrothiophene), [{Pt(R(F))(2)(mu-1kappaP:2eta(2)-PPh(2)C[triple bond]CFc)(2)}Pt(R(F))(2)] and [{Pt(PPh(2)C[triple bond]CtBu)(2)(mu-eta(1):eta(2)-C[triple bond]CFc)(2)}Pt(R(F))(2)] have been determined by X-ray diffraction methods. The electronic spectra and the electrochemical behaviour of all monoplatinum derivatives are discussed, showing a different extent of interaction between the remote ferrocenyl groups when they belong to PPh(2)C[triple bond]CFc or C[triple bond]CFc ligands. For the diplatinum systems and , containing bridging (kappaP:eta(2)-PPh(2)C[triple bond]CFc ) or (eta(1):eta(2)-C[triple bond, length as m-dash]CFc ) ligands, their electrochemical properties were also compared with the parent precursors.

Cis and trans-bis(tetrathiafulvalene-acetylide) platinum(ii) complexes: syntheses, crystal structures, and influence of the ancillary ligands on their electronic properties

“…Among the various bisacetylide metal complexes, those involving a platinum center with various ancillary ligands have also proved their strong propensity to allow electronic interaction by connecting either organic or organometallic electrophores. [10][11][12] In this context, the aim of this work is to investigate the electronic properties of mononuclear platinum complexes containing two TTF acetylide ligands and either diimine or phosphine as ancillary ligands, namely triphenylphosphine, 1,2-bis(diphenylphosphino)ethane (dppe), 2,2′-dipyridyl (bipy) or 4,4′-di-tert-butyl-2,2′-dipyridyl (tBu 2 bipy). Herein, the synthesis, characterization and properties of a series of Pt(II) complexes bearing two monodentate TTF acetylide ligands are reported.…”

Crystal structure of paddle-wheel sandwich-type [Cu2{(CH3)2CO}{μ-Fe(η5-C5H4C[triple-bond]N)2}3](BF4)2·(CH3)2CO

“…The electron-transfer properties of the acetylide function have been investigated intensively by using bridging units of the type -C C-M-C C-(M = transition metal), showing moderate electron communication between two redox-active metallocenyl termini in the mixed-valence species (see, for example: Lang et al, 2006;Vives et al, 2006;Jakob et al, 2009;Díez et al, 2008Díez et al, , 2009Osella et al, 1998;Packheiser et al, 2008;Burgun et al, 2013). The nitrile group is isoelectronic with the acetylide function; Bonniard et al (2011) described how an -N C-C 6 H 4 -C N-linkage between two iron fragments prohibits the electronic interaction between the transition metal atoms, while the isoelectric di(acetylene)phenylene bridge shows a moderate delocalization.…”

(Spectro)electrochemical Properties of Anthracene Containing Triarylamine Platinum(II) Acetylides

“…[15,16] In particular, platinum (II) acetylides have shown to exhibit second-and third-order non-linear optical properties, [17] while simultaneously featuring electrochemical properties [18] that allow the ligand to either donate or withdraw electron density from the Pt(II) center. [19,20] These charge transfer events can be triggered electrochemically by reduction or oxidation events at the ligand [21,22] as well as photochemically in form of metal-to-ligand-(MLCT) [15,23] or ligand-to-metal charge transfer (LMCT) excitations. [24] In this respect, the combination of platinum acetylide complexes with redox active groups allows to switch the optical properties of the material electrochemically by adjusting the oxidation state of the respective ligand.…”