Molecular “Multi‐rod Cable” {[Co(NC5H4–CH=CH–C6H4–CH=CH–C5H4N)(HCOO)2]8}n: A Novel Supramolecular Architecture by Cooperation of Coordination and Stacking Interactions

The cobalt‐formate coordination polymers {[Co(bpyph)(HCOO)₂]₈}_n ( 1 ) (bpyph = 1,4‐bis(2‐(4‐pyridyl)ethenyl)benzene) and {[Co(HCONH₂)₂(HCOO)₂]}_n ( 2 ) have been prepared by interaction of Co(NO₃)₂ · 6 H₂O in formamide solution with generation of formate anion by hydrolysis of the solvent. Coordination polymer 1 reveals an unprecedented example of “molecular multi‐rod cable” architecture, in which eight single “molecular wires” {[Co(bpyph)]}_n are interlinked by bridging formate anions to give infinite octameric chains. The formate groups adopt mono‐, and bi‐ and tridentate bridging and chelate modes of coordination (Co–O 1.966–2.134 Å). The coordination geometry around the cobalt atoms is essentially dominated by the demands for most effective packing of parallel situated polycyclic aromatic ligands, with extensive CH…π, or edge‐to‐face stacking interactions within the single octameric chain as well as between the closest neighbours (C…C separations within this stack are ca. 3.50 Å).     

Self-Assembly of a Three-Dimensional [Ga6(L2)6] Metal–Ligand “Cylinder”

A near trigonal antiprism with metal–metal distances in the nanometer regime is formed by the six metal ions in the crystalline, homochiral [Ga₆(L²)₆] (see structure). This metal–ligand “cylinder” is based on a threefold symmetric, β-diketone ligand, and represents a new geometry for metal–ligand clusters.     

M(H2O)2(4,4′‐bipy)[C6H4(COO)2]·2H2O (M = Mn2+, Co2+) – Zwei isotype Koordinationspolymere mit Schichtstruktur

M(H₂O)₂(4,4′‐bipy)[C₆H₄(COO)₂]·2H₂O (M = Mn²⁺, Co²⁺) – Two Isotypic Coordination Polymers with Layered Structure Monoclinic single crystals of Mn(H₂O)₂(4,4′‐bipy)[C₆H₄(COO)₂]·2H₂O ( 1 ) and Co(H₂O)₂(4,4′‐bipy)[C₆H₄(COO)₂]· 2H₂O ( 2 ) have been prepared in aqueous solution at 80 °C. Space group P2/n (no. 13), Z = 2; 1 : a = 769.20(10), b = 1158.80(10), c = 1075.00(10) pm, β = 92.67(2)°, V = 0.9572(2) nm³; 2 : a = 761.18(9), b = 1135.69(9), c = 1080.89(9) pm, β = 92.276(7)°, V = 0.9337(2) nm³. M²⁺ (M = Mn, Co), which is situated on a twofold crystallographic axis, is coordinated in a moderately distorted octahedral fashion by two water molecules, two oxygen atoms of the phthalate anions and two nitrogen atoms of 4,4′‐biypyridine ( 1 : M–O 219.5(2), 220.1(2) pm, M–N 225.3(2), 227.2(2) pm; 2 : Co–O 212.7(2), 213.7(2) pm, Co–N 213.5(3), 214.9(3) pm). M²⁺ and [C₆H₄(COO)₂)]^2? build up chains, which are linked by 4,4′‐biyridine molecules to yield a two‐dimensional coordination polymer with layers parallel to (001).Thermogravimetric analysis in air of 1 indicated a loss of water of crystallization between 154 and 212 °C and in 2 between 169 and 222 °C.     

[Fe(H2O)5(NO)]2+, the “Brown‐Ring” Chromophore

Although the “brown‐ring” ion, [Fe(H₂O)₅(NO)]²⁺ ( 1 ), has been a research target for more than a century, this poorly stable species had never been isolated. We now report on the synthesis of crystals of a salt of 1 which allowed us to tackle the unique bonding situation on an experimental basis. As a result of the bonding analysis, two stretched, spin‐polarised π‐interactions provide the Fe–NO binding—and challenge the concept of “oxidation state”.     

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 und spektroskopische Charakterisierung von [Rh(SeCN)6]3– und trans‐[Rh(CN)2(SeCN)4]3–, Kristallstruktur von (Me4N)3[Rh(SeCN)6]

Synthesis and Spectroscopic Characterization of [Rh(SeCN)₆]^3– and trans ‐[Rh(CN)₂(SeCN)₄]^3–, Crystal Structure of (Me₄N)₃[Rh(SeCN)₆] Treatment of RhCl₃ with KSeCN in acetone yields a mixture of selenocyanato‐rhodates(III), from which [Rh(SeCN)₆]^3– and trans‐[Rh(CN)₂(SeCN)₄]^3– have been isolated by ion exchange chromatography on diethylaminoethyl cellulose. The X‐ray structure determination on a single crystal of (Me₄N)₃[Rh(SeCN)₆] (trigonal, space group R3, a = 14.997(2), c = 24.437(3) Å, Z = 6) reveals, that the compound crystallizes isotypically to (Me₄N)₃[Ir(SCN)₆]. The exclusively via Se coordinated selenocyanato ligands are bonded with the average Rh–Se distance of 2.490 Å and the Rh–Se–C angle of 104.6°. In the low temperature IR and Raman spectra the metal ligand stretching modes ν(RhSe) of (n‐Bu₄N)₃[Rh(SeCN)₆] ( 1 ) and trans‐(n‐Bu₄N)₃[Rh(CN)₂(SeCN)₄] ( 2 ) are in the range of 170–250 cm^–1. In 2 ν_as(CRhC) is observed at 479 cm^–1. The vibrational spectra are assigned by normal coordinate analysis based on the molecular parameters of the X‐ray determination. The valence force constants are f_d(RhSe) = 1.08 ( 1 ), 1.10 ( 2 ) and f_d(RhC) = 3.14 mdyn/Å ( 2 ). f_d(RhS) = 1.32 mdyn/Å is determined for [Rh(SCN)₆]^3–, which has not been calculated so far. The ¹⁰³Rh NMR resonances are 2287 ( 1 ), 1680 ppm ( 2 ) and the ⁷⁷Se NMR resonances are –32.7 ( 1 ) and –110.7 ppm ( 2 ). The Rh–C bonding of the cyano ligand in 2 is confirmed by a dublett in the ¹³C NMR spectrum at 136.3 ppm.     

Formation of a Ring-Shaped Reduced “Metal Oxide” with the Simple Composition [(MoO3)176(H2O)80H32]

The largest inorganic molecular system so far , [(MoO₃)₁₇₆(H₂O)₈₀H₃₂] ( 1 ; the picture on the right shows the polyhedral representation), which has been characterized by X-ray structure analysis, possesses a cavity of diameter 2.3 nm and remarkably shows the stoichiometry of a (reduced) protonated and hydrated “molecular molybdenum trioxide”. It is formed by reduction of an aqueous solution of lithium molybdate with tin(II ) chloride at very high H⁺ concentrations.     

The Mixed-Valent (μ-Nitrido)dimanganese Complex Anion [(CN)5MnV(μ-N)MnII(CN)5]6−

Localized valencies are displayed by the Mn^V–Mn^II complex ion 1 . This is the key finding from X-ray structure analysis, as well as vibrational and EPR spectroscopic invesigations on 1 obtained by the reaction of manganese(II ) and [Mn^v(N)(CN)₅]³⁻ salts in aqueous 1 M NaCN solution. Remarkably, the asymmetry is induced by the nitrogen atom bridge.     

[Am(C5Me4H)3]: An Organometallic Americium Complex

We report the small‐scale synthesis, isolated yield, single‐crystal X‐ray structure, ¹H NMR solution spectroscopy /solid‐state UV/Vis‐nIR spectroscopy, and density functional theory (DFT)/ab initio wave function theory calculations on an Am³⁺ organometallic complex, [Am(C₅Me₄H)₃] ( 1 ). This constitutes the first quantitative data on Am?C bonding in a molecular species.     

Synthese,Kristallstruktur und Eigenschaften der käfigartigen,sechsbasigen Säure P12S12N8(NH)6 · 14 H2O sowie ihrer Salze Li6[P12S12N14] · 26 H2O, (NH4)6[P12S12N14] · 10 H2O und K6[P12S12N14] · 8 H2O

Syntheses, Crystal Structure, and Properties of the Cage‐like, Hexaacidic P₁₂S₁₂N₈(NH)₆ · 14 H₂O and its Salts Li₆[P₁₂S₁₂N₁₄] · 26 H₂O, (NH₄)₆[P₁₂S₁₂N₁₄] · 10 H₂O, and K₆[P₁₂S₁₂N₁₄] · 8 H₂O The cage‐like acid P₁₂S₁₂N₈(NH)₆ · 14 H₂O was obtained by the reaction of KSCN with P₄S₁₀ via the formation of K₆[P₁₂S₁₂N₁₄] · 8 H₂O and subsequent ion exchange reactions in aqueous solution. Starting from the acid the salts Li₆[P₁₂S₁₂N₁₄] · 26 H₂O and (NH₄)₆[P₁₂S₁₂N₁₄] · 10 H₂O were synthesized. According to X‐ray single‐crystal structure analyses the compounds are built up by isosteric P–N cages [P₁₂S₁₂N^[3]₈N^[2]₆]^6–. Each of them is made up of twelve P₃N₃ rings, which exclusively exhibit the boat conformation. The cages have the idealized symmetry 2/m3; P₁₂S₁₂N₈(NH)₆ · 14 H₂O: P1, a = 1119.11(7), b = 1123.61(7), c = 1125.80(6) pm, α = 80.186(4), β = 60.391(4), γ = 60.605(4)°, Z = 1; Li₆[P₁₂S₁₂N₁₄] · 26 H₂O: Fm3, a = 1797.4(1) pm, Z = 4; (NH₄)₆[P₁₂S₁₂N₁₄] · 10 H₂O: P6₃, a = 1153.2(1), c = 2035.6(2) pm, Z = 2; K₆[P₁₂S₁₂N₁₄] · 8 H₂O: R3c, a = 1142.37(5), c = 6009.6(3) pm, Z = 6. In the crystal the cages of the acid are crosslinked via hydrate molecules by hydrogen bonds. The cations in the salts show a high‐mobility and are located between the cages.