Isolation and characterization of the dimetal decacarbonyl dication [Ru(CO)] and the metal-only Lewis-pair [Ag{Ru(CO)}] .

The reaction of Ag with Ru(CO) in a CO atmosphere under concommittant irradiation with UV-light yields a salt of the metal-only Lewis-pair [Ag{Ru(CO)}]. Switching the silver cation for a more process-selective deelectronator yields a salt of the homoleptic transition metal carbonyl cation [Ru(CO)], which fills the gap between the known cations [Ru(CO)] and [Ru(CO)]. The amount of π-backdonation in this series was studied by a combination of vibrational spectroscopy and computed relaxed force constants.

Pushing redox potentials to highly positive values using inert fluorobenzenes and weakly coordinating anions.

While the development of weakly coordinating anions (WCAs) received much attention, the progress on weakly coordinating and inert solvents almost stagnated. Here we study the effect of strategic F-substitution on the solvent properties of fluorobenzenes CFH (xFB, x = 1-5). Asymmetric fluorination leads to dielectric constants as high as 22.

Synthesis and Characterization of a Copper Dinitrogen Complex Supported by a Weakly Coordinating Anion.

We report the synthesis and full characterization of the copper dinitrogen complex [(η-N)Cu{Al(OR)}] 2 (R=C(CF)) prepared by a cascade metathesis reaction of Ag[Al(OR)] with CuI-excess in iso-perfluorohexane (i-pfh) under N atmosphere. Title compound 2 features an extraordinarily high N stretching frequency at 2313/2314 cm (IR/Raman) and was characterized by single-crystal and powder X-ray diffractometry. Quantum chemical charge displacement analysis based on natural orbitals of chemical valence (CD-NOCV) indicates that the copper-dinitrogen interaction is still governed by weak π-backdonation, but is significantly reduced compared to all literature-known transition metal dinitrogen complexes.

Utilizing the Perfluoronaphthalene Radical Cation as a Selective Deelectronator to Access a Variety of Strongly Oxidizing Reactive Cations.

A selective deelectronation reagent with very high potential of +2.00 (solution)/+2.41 V (solid-state) vs.

Homoleptic Transition Metal Carbonyl Cations: Synthetic Approaches, Characterization and Follow-Up Chemistry.

ConspectusCarbon monoxide, CO, is one of the most important ligands in organometallic chemistry. It is an excellent π-acceptor and a moderate σ-donor. Therefore, most of the known transition metal carbonyls (TMCs) exhibit a zerovalent or even negative metal oxidation state (OS) of up to -4.

Isolation, Structural and Physical Characterization as well as Reactivity of Persistent Acenium Radical Cation Salts.

The unsubstituted acenium radical cations (ARCs) are extremely sensitive and were hitherto only studied in situ, i. e. in the gas phase, as dilute solutions in strong acids or by matrix isolation spectroscopy at about 10 K.

Coordination versus Insertion: On the Interaction of 5 d-Transition Metal Carbonyl Clusters with Silver(I).

The title silver(I) complex salts [Ag{Re (CO) }{Re(CO) } ] [Al(OR ) ] (AgRe ; OR =-OC(CF ) ) and [Ag{Ir (CO) } ] [Al(OR ) ] (AgIr ) form upon reaction of Ag [Al(OR ) ] and the transition metal carbonyls (TMCs) Re (CO) and Ir (CO) respectively. The solid-state structure of the AgRe cluster shows an unexpected asymmetric coordination motif, wherein the silver(I) cation has inserted into the Re-Re bond of one Re (CO) moiety, while the other dirhenium carbonyl coordinates only over one metal atom towards the silver(I) cation. The AgIr cluster is formed by the edge-on coordination of two Ir tetrahedra and the silver cation in a D symmetric fashion with a torsion angle of 46.

Towards clustered carbonyl cations [M(CO)] (M = Ru, Os): the need for innocent deelectronation.

To access the hitherto almost unknown class of clustered transition metal carbonyl cations, the trimetal dodecacarbonyls M(CO) (M = Ru, Os) were reacted with the oxidant Ag[WCA], but yielded the silver complexes [Ag{M(CO)}][WCA] (WCA = [Al(OR)], [F{Al(OR)}]; R = -OC(CF)). Addition of further diiodine I to increase the redox potential led for M = Ru non-specifically to divalent mixed iodo-Ru-carbonyl cations. With [NO], even the N-O bond was cleaved and led to the butterfly carbonyl complex cation [RuN(CO)] in low yield.

Introducing the Perfluorinated Cp* Ligand into Coordination Chemistry.

The reaction of AgBF and [Rh(COD)Cl] (COD=1,5-cyclooctadiene) in presence of [NEt ][C (CF ) ] afforded the fluorocarbon soluble complex [Rh(COD)(C (CF ) )] by salt metathesis. This complex represents the first example for a successful coordination of the weakly basic [C (CF ) ] ligand, since its first synthesis in 1980. In addition to [Rh(COD)(C (CF ) )] also the byproduct [Rh(COD)(C (CF ) H)] was isolated and fully characterized.

Increasing the oxidation power of TCNQ by coordination of B(CF).

The oxidation power of the cyanocarbon TCNQ (tetracyano-quinodimethane) can be significantly increased to approximately = +0.9 V CpFe by coordination of up to four equivalents of the strong fluorinated Lewis acid B(CF), resulting in a highly reactive but easy-to-use oxidation system. Thianthrene and tris(4-bromophenyl)amine were oxidized to the corresponding radical cations.

Eightfold Electrophilic Methylation of Octacyanotungstate [W(CN)]: Preparation of Homoleptic, Eight-Coordinate Methyl Isocyanide Complexes [W(CNMe)].

Homoleptic eightfold coordinated methyl isocyanide complexes of W(IV) and W(V) have been prepared for the first time. The reaction of [NBu][W(CN)] with methyl triflate (MeOTf) gives [W(CNMe)][OTf]. The even stronger methylating mixture of methyl fluoride (MeF) and arsenic pentafluoride (AsF) in liquid sulfur dioxide (SO) is able to fully alkylate both [NBu][W(CN)] and [NBu][W(CN)].

Isolation and Structural Characterization of Eightfold Protonated Octacyanometalates [M(CNH) ] (M=Mo , W ) from Superacids.

Octacyanometalates K [Mo(CN) ] and K [W(CN) ] are completely protonated in superacidic mixtures of anhydrous hydrogen fluoride and antimony pentafluoride. The resulting hydrogen isocyanide complexes [Mo(CNH) ] [SbF ] and [W(CNH) ] [SbF ] are the first examples of eight-coordinate homoleptic metal complexes containing hydrogen isocyanide (CNH) ligands. The complexes were crystallographically characterized, revealing hydrogen-bonded networks with short N⋅⋅⋅H⋅⋅⋅F contacts.

Crystal structure of [K(18-crown-6)] [Pt(CN)].

In the title compound, di-μ-cyanato-1:2κ :;2:3κ :-di-cyanato-2κ -bis-(1,4,7,10,13,16-hexa-oxa-cyclo-octa-deca-ne)-1κ ;3κ -1,3-dipotassium(I)-2-platinum(II), [KPt(CN)(CHO)] or [K(18-crown-6)]·[Pt(CN)], two -orientated cyano groups of the square-planar [Pt(CN)] dianion (Pt site symmetry ) bind to one potassium ion each, which are additionally coordinated by the six O atoms of 18-crown-6. No Pt⋯Pt inter-actions occur in the crystal, but very weak Pt⋯H contacts (2.79 Å) are observed.