Capturing the missing [AgF₂]⁻ anion within an Ru₂(iii/iii) dimeric dumbbell complex

Abstract

The complex {[Ru2(ap)4]2[AgF2]}[BF4]3 ({2}[BF4]3, ap = 2-anilinopyridine), containing the [AgF2](-) anion ligated to two [Ru2](6+) cores, is prepared, characterized, and compared to dimeric dumbbell-type structures, monomeric Ru2 structures, as well as the known set of dihalo coinage-metalate anions. X-ray crystallography indicates that the Ru-Ru and Ru-F distances are rather short, 2.2835(3) Å and 2.054(1) Å, respectively, while the Ag-F distance of 2.274(1) Å is longer than that calculated for the free/un-ligated anion. Cyclic voltammetry in dichloromethane indicates that, while some of {2}(3+) breaks apart into an [Ru2(ap)4F](+) ([3](+)) monomer in solution, the remaining dimer has a single reversible two-electron redox feature for the Ru2(6/5+) couple that is at a lower potential than that of [3](+). This is one of the few examples of a ligated dihalo coinage-metalate, and it is the first example of a coinage metal difluoride anion, either free or ligated.

[{TcI(NO)(LOMe)(PPh3)Cl}2Ag](PF6) and [TcII(NO)(LOMe)(PPh3)Cl](PF6): Two Unusual Technetium Complexes with a “Kläui‐type” Ligand

“…The most remarkable feature of the compound is the central {TcÀ ClÀ AgÀ ClÀ Tc} + unit, which is established between two [Tc(NO)(L OMe )(PPh 3 )Cl] complexes in the solid state. The ClÀ AgÀ Cl bridge is linear, while TcÀ ClÀ Ag angles of 82.88 (7) and 86.37 (6) have linear XÀ AgÀ X units, [32][33][34] while the corresponding angles in [{Re(Tp)(N-ptol)(Ph)I} 2 Ag](PF 6 ) and [M((C,N,N',P ligand)(AN)Cl} 2 Ag](SbF 6 ) 3 (M = Rh, Ir) are between 120 and 125°. [35,36] The AgÀ Cl bond in all these compounds are around 2.5 Å as we have found for complex 4 of the present work.…”

The Stepwise Reaction of Rhodium and Iridium Complexes of Formula [MCl2(κ4C,N,N′,P−L)] with Silver Cations: A Case of trans‐Influence and Chiral Self‐Recognition

“…As far as we know, only four previous structures exhibit unsupported X 2 Ag bridges (X=halogen atom). Remarkably, in three of them, namely, (NBu 4 ) x [{Pt(C 6 Cl 5 ) 2 ( μ ‐Cl)} 2 Ag] x , [{PtCl(Me)( N , N ‐chelate)( μ ‐Cl)} 2 Ag], and [{Ru 2 (ap) 4 ( μ ‐Cl)} 2 Ag], linear Cl‐Ag‐Cl bridges are present, while the compound [{TpRe( N‐p ‐tol)‐(Ph)( μ ‐I)} 2 Ag] exhibits a smaller angle (124.3°) . In the latter, the silver atom additionally interacts with two carbon atoms of two aromatic rings, each one belonging to one of the two mononuclear subunits [Ag−C, 2.528(13) Å] completing a distorted‐tetrahedral environment for the silver.…”

Forging Ru–Csp2 Bonds in Paddlewheel Complexes Using the Lithium–Halogen Exchange Reaction

“…Since then, interest has burgeoned in the study of Ru 2 L 4 (CCR) n type complexes ( n = 1, 2) . Because of the extended conjugation along the Ru 2 -polyalkynyl chains and the robust redox states of the Ru 2 n + ( n = 4–6) paddlewheel motif, the wirelike characteristics of these molecules, many of which are based on Ru 2 ( ap ) 4 , have been studied by several laboratories, including ours. − This has enabled incorporation of Ru 2 ( ap ) 4 -alkynyl molecules in nonvolatile flash memory devices. , The diverse utility of Ru 2 ( ap ) 4 -containing molecules in forming Ru-Ru-oxo species and capturing the exotic anion AgF 2 – has been demonstrated by Berry and co-workers. − It is noteworthy that all structurally characterized organometallic diruthenium paddlewheel complexes feature either one or two alkynyl axial ligand(s) or smaller ligands such as CN – and CO . Specifically, the Ru– Ru – C sp 2 bond in a paddlewheel motif is a much sought after target, since nothing is known about the bonding, structure, and reactivity of these species.…”