Darstellung,Mössbauer- und Schwingungsspektren der Komplexe [SnCl4F]⊖, [SnCl4(NCS)]⊖ und [SnCl4(NCS)2]2⊖

Preparation, Mössbauer and Vibrational Spectra of the Complexes [SnCl₄F]^?, [SnCl₄(NCS)]^?, and [SnCl₄(NCS)₂]^2? N(CH₂)₄F and N(CH₂)₄SCN react in liquid SO₂ with SnCl₄ yielding the adducts [N(CH₃)₄][SnCl₄F] (I), [N(CH₃)₄][SnCl₄(NCS)] (II) and [N(CH₃)₄]₂[SnCl₄(NCS)₂] (III).respectively. Mössbauer and vibrational spectra indicate for the anion of I a fluoro-bridged species, which is probably tetrameric like the isoelectronic SbCl₄F. For II dimeric moieties are proposed with bridging S-atoms, while [SnCl₄(NCS)₂]^2? has an octahedral structure with N-bonded isothiocyanate groups in the trans-positions.     

Lamellare Schichten auf der Grundlage von Wasserstoffbrücken und π‐Stapelung: Kristallstrukturen der Metall(II)‐Komplexe [Cd{C6H4(SO2)2N}2(H2O)4] und [Cu{C6H4(SO2)2N}2(H2O)4]·2 H2O

The title complexes, obtained by treating hot aqueous solutions of ortho‐benzenedisulfonimide with solid CdCO₃ or CuO, have been characterized by low‐temperature X‐ray diffraction (both triclinic, space group P&1macr;, Z = 1, metal ions on inversion centres). The cations have trans‐octahedral coordinations provided by two Cd‐N bonded or two Cu‐O bonded anions and four water molecules [Cd‐N 234.7(2) pm; Cu‐O(anion) 240.4(1) pm, elongated by Jahn‐Teller distortion]; the copper complex contains two further, non‐coordinating, water molecules per formula unit. In both structures, the uncharged zero‐dimensional building blocks are associated via strong hydrogen bonds O(W)‐H···A and one short C‐H···O bond to form two‐dimensional assemblies comprising an internal polar lamella of metal cations, (SO₂)₂N groups and water molecules, and hydrophobic peripheral regions consisting of vertically protruding benzo rings. Carbocycles drawn alternatingly from adjacent layers form π‐stacking arrays, in which the parallel aromatic rings display intercentroid distances in the range 365‐385 pm and vertical ring spacings in the range 345‐385 pm.     

Synthese von Kupfer- und Silberkomplexen mit fünfzähnigen N,S- und sechszähnigen N,O-Chelatliganden – Charakterisierung und Kristallstrukturen von {Cu2[C6H4(SO2)NC(O)]2(C5H5N)4}, {Cu2[C5H3N(CHNC6H4SCH3)2]2}(PF6)2 und {Ag[C5H3N(CHNC6H4SCH3)2]}PO2F2

Synthesis of Copper and Silver Complexes with Pentadentate N,S and Hexadentate N,O Chelate Ligands – Characterization and Crystal Structures of {Cu₂[C₆H₄(SO₂)NC(O)]₂(C₅H₅N)₄}, {Cu₂[C₅H₃N(CHNC₆H₄SCH₃)₂]₂}(PF₆)₂, and {Ag[C₅H₃N(CHNC₆H₄SCH₃)₂]}PO₂F₂ In the course of the reaction of copper(II)-acetate monohydrate with 2,2′-bisbenzo[d][1,3]thiazolidyl in methanol the organic component is transformed to N,N′-bis-(2-thiophenyl)ethanediimine and subsequently oxidized to the N,N′-bis-(2-benzenesulfonyl)ethanediaciddiamide H₄BBSED, which coordinates in its deprotonated form two Cu²⁺ ions. Crystallisation from pyridine/n-hexane yields [Cu₂(BBSED)(py)₄] · MeOH. It forms triclinic crystals with the space group P1 and a = 995.5(2) pm, b = 1076.1(3) pm, c = 1120.7(2) pm, α = 104.17(1)°, β = 105.28(1)°, γ = 113.10(1)° and Z = 1. In the centrosymmetrical dinuclear complex the copper ions are coordinated in a square-pyramidal arrangement by three nitrogen and two oxygen atoms. The Jahn-Teller effect causes an elongation of the axial bond by approximately 30 pm. The reactions of the pentadentate ligand 2,6-Bis-[(2- methylthiophenyl)-2-azaethenyl]pyridine BMTEP with salts of copper(I), copper(II) and silver(I) yield the complexes [CU₂(BMTEP)₂](PF₆)₂, [Cu(BMTEP)]X₂ (X = BF, C1O) and [Ag(BMTEP)]X (X = PO₂F, ClO). [Cu₂(BMTEP)₂](PF₆)₂ crystallizes from acetone/diisopropyl- ether in form of monoclinic crystals with the space group C2/c, and a = 1833.2(3) pm, b = 2267.30(14) pm, c = 1323.5(2) pm, β= 118.286(5)°, and 2 = 4. In the dinuclear complex cation with the symmetry C₂ the copper ions are tetrahedrally coordinated by two bridging BMTEP ligands. The Cu? Cu distance of 278.3pm can be interpreted with weak Cu? Cu interactions which also manifest itself in a temperature independent paramagnetism of 0.45 B.M. The monomeric silver complex [Ag(BMTEP)]PO₂F₂ crystallizes from acetone/thf in the triclinic space group P1 with a = 768.7(3) pm, b = 1074.0(5) pm, c = 1356.8(5) pm, α = 99.52(2)°, β = 96.83(2)°, γ = 99.83(2)° and Z = 2. The central silver ion is coordinated by one sulfur and three nitrogen atoms of the ligand in a planar, semicircular arrangement. The bond lengths Ag? N = 240.4–261.7 and Ag? S = 257.2 pm are significantly elongated in comparison with single bonds.     

Das Hexagallan [Ga6{SiMe(SiMe3)2}6] und das closo‐Hexagallanat [Ga6{Si(CMe3)3}4(CH2C6H5)2]2— — der Übergang zu einem ungewöhnlichen precloso‐Cluster

The Hexagallane [Ga₆{SiMe(SiMe₃)₂}₆] and the closo‐Hexagallanate [Ga₆{Si(CMe₃)₃}₄ (CH₂C₆H₅)₂]^2— — the Transition to an Unusual precloso‐Cluster The closo hexagallanate [Ga₆R₄(CH₂Ph)₂]^2— (R = Si^tBu₃) as well as the hexagallane Ga₆R₆ (R = SiMe(SiMe₃)₂) with only six cluster electron pairs were isolated from reactions of “GaI” with the corresponding silanides. The structure of the latter is derived from an octahedron by a Jahn‐Teller‐distortion and is different from the capped trigonal bipyramidal one expected by the Wade‐Mingos rules. Both compounds were characterized by X‐ray crystallography. The bonding is discussed with simplified Ga₆H₆ and Ga₆H₆^2— models via DFT methods.     

Anionische Nickel-Pseudohalogenid-Komplexe der Typen [Ni{N(CN)2}3]− und [Ni{N(CN)2}2(NCS)2]2−

Anionie Nickel Pseudohalide Complexes of the Types [Ni{N(CN)₂}₃]^? and [Ni{N(CN)₂}₂(NCS)₂]^2? The preparation of a new type of anionic pseudohalide complexes of nickel [Ni{N(CN)₂}₃]^? and of mixed thiocyanate-dicyanamide complexes [Ni{N(CN)₂}₂(NCS)₂]^2? is reported. The structures of the complexes are discussed on the basis of IR- and magnetic measurements. The new compounds are representing polymer octahedral complexes with a bridging function of the dicyanamide ligands.     

[Fe2{SeC6H2‐2,4,6‐Ph3}2{N(SiMe3)2}2] and [Fe2{SeC6H2‐2,4,6‐Ph3}4], the First Three‐Coordinate Selenolatoiron Complexes

In a controlled manner , half or all the bis(trimethylsilyl)amido ligands of 1 can be replaced by selenolato ligands, resulting in the first selenolatoiron complexes 2 and 3 with three‐coordinate iron centers. They are stabilized by secondary metal–framework bonds (here metal–carbon) and could, since they are coordinatively unsaturated, possibly serve as model compounds of the FeMo cofactor of nitrogenases.