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1.
Dr. Markus Ströbele Cristina Castro Prof. Dr. Reinhold F. Fink Prof. Dr. H.‐Jürgen Meyer 《Angewandte Chemie (International ed. in English)》2016,55(15):4814-4817
The preparation of tungsten iodides in large quantities is a challenge because these compounds are not accessible using an easy synthesis method. A new, remarkably efficient route is based on a halide exchange reaction between WCl6 and SiI4. The reaction proceeds at moderate temperatures in a closed glass vessel. The new compounds W3I12 (W3I8?2 I2) and W3I9 (W3I8? I2) containing the novel [W3I8] cluster are formed at 120 and 150 °C, and remain stable in air. W3I12 is an excellent starting material for the synthesis of other metal‐rich tungsten iodides. At increasing temperature these trinuclear clusters undergo self‐reduction until an octahedral tungsten cluster is formed in W6I12. The synthesis, structure, and an analysis of the bonding of compounds containing this new trinuclear tungsten cluster are presented. 相似文献
2.
Florian Pachel Dr. Markus Ströbele Carl P. Romao David Enseling Thomas Jüstel Prof. Dr. Hans-Jürgen Meyer 《欧洲无机化学杂志》2023,26(19):e202300096
The new heteroleptic tungsten iodide cluster compound [W6I12(NCC6H5)2] is presented. The synthesis is carried-out from Cs2W6I14 and ZnI2 under solvothermal conditions in benzonitrile solution, yielding red cube-shaped crystals. [W6I12(NCC6H5)2] represents a heteroleptic [W6I8]-type cluster bearing four apical iodides and two benzonitrile ligands. Molecular [W6I12(NCC6H5)2] clusters form a robust hydrogen bridged crystal structure with high thermal stability and high resistibility against hydrolysis. The electronic structure is analyzed by quantum chemical methods of the calculated electron localization function (ELF) and the band structure. Photoluminescence measurements are performed to verify and describe the photophysical properties of [W6I12(NCC6H5)2]. Finally, the photocatalytic properties of [W6I12(NCC6H5)2] are evaluated as a proof-of-concept. 相似文献
3.
Wenjiang Huang Jinfang Zhang Jianghua Li Chi Zhang 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(2):123-126
In the polymeric title compound, [CuI(C10H8N4)]n, the CuI atom is in a four‐coordinated tetrahedral geometry, formed by two I atoms and two pyridine N atoms from two different 4,4′‐(diazenediyl)dipyridine (4,4′‐azpy) ligands. Two μ2‐I atoms link two CuI atoms to form a planar rhomboid [Cu2I2] cluster located on an inversion centre, where the distance between two CuI atoms is 2.7781 (15) Å and the Cu—I bond lengths are 2.6290 (13) and 2.7495 (15) Å. The bridging 4,4′‐azpy ligands connect the [Cu2I2] clusters into a two‐dimensional (2‐D) double‐layered grid‐like network [parallel to the (10) plane], with a (4,4)‐connected topology. Two 2‐D grid‐like networks interweave each other by long 4,4′‐azpy bridging ligands to form a dense 2‐D double‐layered network. To the best of our knowledge, this interwoven 2‐D→2‐D network is observed for the first time in [Cu2I2]–organic compounds. 相似文献
4.
The new adduct W4Br10 · 2SbBr3 and the new binary compound W4Br10 were obtained as products in a reaction cascade in which WBr6 was reacted with elemental antimony at successively increased temperatures. The crystal structures of both compounds were refined from X‐ray powder diffraction data and their electronic structures were analyzed by MO calculations. The cluster compounds W4Br10 · 2SbBr3 and W4Br10 appear as intermediates in the solid state nucleation of W6Br12. The overall reaction cascade involves tungsten clusters having tetrahedral (W4), square pyramidal (W5) and finally octahedral (W6) cluster cores. 相似文献
5.
Azizolla Beheshti William Clegg Nahid Ebrahimi Filoori Luca Russo 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(5):m149-m153
Two polymorphs of the title compound, (C8H20N)[W2S4(S4)(C15H22BN6)], have been obtained unexpectedly by attempted recrystallization of a mixed‐metal–sulfur cluster complex from different solvents. The dinuclear complex anion contains WV in two different coordination environments, one of them distorted octahedral with a tris(pyrazolyl)borate anion, a terminal sulfide and two bridging sulfide ligands, the other distorted square‐pyramidal with a terminal sulfide, two bridging sulfide and a chelating tetrasulfide ligand. The three independent anions in the two polymorphs have essentially the same geometry. The central W2S2 ring is a slightly folded rhombus with acute angles at the S atoms, and the WS4 chelate ring is an envelope with one noncoordinating S atom as the flap. The second polymorph, with Z′ = 2 and pseudo‐inversion symmetry relating the anions of the asymmetric unit, also displays pseudo‐translation features in its layer structure, and all examined crystals were found to be twinned, possibly as a consequence of this structural feature. 相似文献
6.
Crystal Structures of Bacterial (6‐4) Photolyase Mutants with Impaired DNA Repair Activity
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Kalinga Bowatte Dennis Kwiatkowski Esther Mittmann Heba Qasem Norbert Krauß Xiaoli Zeng Zhong Ren Patrick Scheerer Xiaojing Yang Tilman Lamparter 《Photochemistry and photobiology》2017,93(1):304-314
PhrB from Agrobacterium fabrum is the first prokaryotic photolyase which repairs (6‐4) UV DNA photoproducts. The protein harbors three cofactors: the enzymatically active FAD chromophore, a second chromophore, 6,7‐dimethyl‐8‐ribityllumazine (DMRL) and a cubane‐type Fe‐S cluster. Tyr424 of PhrB is part of the DNA‐binding site and could provide an electron link to the Fe‐S cluster. The PhrBY424F mutant showed reduced binding of lesion DNA and loss of DNA repair. The mutant PhrBI51W is characterized by the loss of the DMRL chromophore, reduced photoreduction and reduced DNA repair capacity. We have determined the crystal structures of both mutants and found that both mutations only affect local protein environments, whereas the overall fold remained unchanged. The crystal structure of PhrBY424F revealed a water network extending to His366, which are part of the lesion‐binding site. The crystal structure of PhrBI51W shows how the bulky Trp leads to structural rearrangements in the DMRL chromophore pocket. Spectral characterizations of PhrBI51W suggest that DMRL serves as an antenna chromophore for photoreduction and DNA repair in the wild type. The energy transfer from DMRL to FAD could represent a phylogenetically ancient process. 相似文献
7.
Thorsten Hummel Agnieszka Mo‐Hummel Markus Strbele Hans‐Jürgen Meyer 《无机化学与普通化学杂志》2019,645(12):831-834
Alkaline earth tungsten iodide clusters AE[W6I14] with AE = Mg, Ca, Sr, Ba and the solvated compound [Ca(C2H6SO)6][W6I14] were prepared and structurally characterized. A new synthesis was employed, starting from W6I22, which is an exceptional compound among binary tungsten iodides because it is soluble in common polar organic solvents. As evidence for the wide range of the applicability of W6I22, we report the synthesis of the new AE[W6I14] compounds in comparison to a solid‐state reaction departing from W3I12. 相似文献
8.
The heteroleptic cluster compound (W6I8)Cl4 was prepared by thermal conversion of the homoleptic clusters W6I12 and W6Cl12 at 700 °C to yield a bright yellow powder. The presence of the smaller chlorido ligands in apical positions of [(W6I8)Cl6]2– creates nearly spherically clusters showing thermal and chemical inertness. Photoluminescence studies revealed a strong red phosphorescence from excited spin‐triplet states. 相似文献
9.
Prof. Dr. Michael Stollenz Dr. Jeffery E. Raymond Dr. Lisa M. Pérez Jessica Wiederkehr Dr. Nattamai Bhuvanesh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(7):2396-2405
Linearly arranged metal atoms that are embedded in discrete molecules have fascinated scientists across various disciplines for decades; this is attributed to their potential use in microelectronic devices on a submicroscopic scale. Luminescent oligonuclear Group 11 metal complexes are of particular interest for applications in molecular light‐emitting devices. Herein, we describe the synthesis and characterization of a rare, homoleptic, and neutral linearly arranged tetranuclear CuI complex that is helically bent, thus representing a molecular coil in the solid state. This tetracuprous arrangement dimerizes into a unique octanuclear assembly bearing a linear array of six CuI centers with two additional bridging cuprous ions that constitute a central pseudo‐rhombic CuI4 cluster. The crystal structure determinations of both complexes reveal close d10???d10 contacts between all cuprous ions that are adjacent to each other. The dynamic behavior in solution, DFT calculations, and the luminescence properties of these remarkable complexes are also discussed. 相似文献
10.
Pattiya Krinchampa Kittipong Chainok Siriporn Phengthaisong Sujittra Youngme Filip Kielar Nanthawat Wannarit 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(12):960-965
One of most interesting systems of coordination polymers constructed from the first‐row transition metals is the porous ZnII coordination polymer system, but the numbers of such polymers containing N‐donor linkers are still limited. The title double‐chain‐like ZnII coordination polymer, [Ag2Zn(CN)4(C10H10N2)2]n, presents a one‐dimensional linear coordination polymer structure in which ZnII ions are linked by bridging anionic dicyanidoargentate(I) units along the crystallographic b axis and each ZnII ion is additionally coordinated by a terminal dicyanidoargentate(I) unit and two terminal 1‐benzyl‐1H‐imidazole (BZI) ligands, giving a five‐coordinated ZnII ion. Interestingly, there are strong intermolecular AgI…AgI interactions between terminal and bridging dicyanidoargentate(I) units and C—H…π interactions between the phenyl rings of BZI ligands of adjacent one‐dimensional linear chains, providing a one‐dimensional linear double‐chain‐like structure. The supramolecular three‐dimensional framework is stabilized by C—H…π interactions between the phenyl rings of BZI ligands and by AgI…AgI interactions between adjacent double chains. The photoluminescence properties have been studied. 相似文献
11.
Mohamed Al Amine Benhacine Malika Hamadne Sofiane Bouacida Hocine Merazig 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(3):243-250
The oxalate dianion is one of the most studied ligands and is capable of bridging two or more metal centres and creating inorganic polymers based on the assembly of metal polyhedra with a wide variety of one‐, two‐ or three‐dimensional extended structures. Yellow single crystals of a new mixed‐metal oxalate, namely catena‐poly[[diaquasodium(I)]‐μ‐oxalato‐κ4O1,O2:O1′,O2′‐[diaquairon(III)]‐μ‐oxalato‐κ4O1,O2:O1′,O2′], [NaFe(C2O4)2(H2O)4]n, have been synthesized and the crystal structure elucidated by X‐ray diffraction analysis. The compound crystallizes in the noncentrosymmetric space group I41 (Z = 4). The asymmetric unit contains one NaI and one FeIII atom lying on a fourfold symmetry axis, one μ2‐bridging oxalate ligand and two aqua ligands. Each metal atom is surrounded by two chelating oxalate ligands and two equivalent water molecules. The structure consists of infinite one‐dimensional chains of alternating FeO4(H2OW1)2 and NaO4(H2OW2)2 octahedra, bridged by oxalate ligands, parallel to the [100] and [010] directions, respectively. Because of the cis configuration and the μ2‐coordination mode of the oxalate ligands, the chains run in a zigzag manner. This arrangement facilitates the formation of hydrogen bonds between neighbouring chains involving the H2O and oxalate ligands, leading to a two‐dimensional framework. The structure of this new one‐dimensional coordination polymer is shown to be unique among the AIMIII(C2O4)2(H2O)n series. In addition, the absorption bands in the IR and UV–Visible regions and their assignments are in good agreement with the local symmetry of the oxalate ligand and the irregular environment of iron(III). The final product of the thermal decomposition of this precursor is the well‐known ternary oxide NaFeO2. 相似文献
12.
Guang‐Tao Xu Liang‐Liang Wu Xiao‐Yong Chang Tim Wai Hung Ang Wai‐Yeung Wong Jie‐Sheng Huang Chi‐Ming Che 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(45):16443-16452
Supramolecular ensembles adopting ring‐in‐ring structures are less developed compared with catenanes featuring interlocked rings. While catenanes with inter‐ring closed‐shell metallophilic interactions, such as d10–d10 AuI–AuI interactions, have been well‐documented, the ring‐in‐ring complexes featuring such metallophilic interactions remain underdeveloped. Herein is described an unprecedented ring‐in‐ring structure of a AuI‐thiolate Au12 cluster formed by recrystallization of a AuI‐thiolate Au10 [2]catenane from alkane solvents such as hexane, with use of a bulky dibutylfluorene‐2‐thiolate ligand. The ring‐in‐ring AuI‐thiolate Au12 cluster features inter‐ring AuI–AuI interactions and underwent cluster core change to form the thermodynamically more stable Au10 [2]catenane structure upon dissolving in, or recrystallization from, other solvents such as CH2Cl2, CHCl3, and CH2Cl2/MeCN. The cluster‐to‐cluster transformation process was monitored by 1H NMR and ESI‐MS measurements. Density functional theory (DFT) calculations were performed to provide insight into the mechanism of the “ring‐in‐ring? [2]catenane” interconversions. 相似文献
13.
Single-crystals of a new compound W5Br12 · SbBr3 (I) were isolated as a reaction product from the reduction of WBr6 with elemental antimony at 250°C. The crystal structure was determined by single-crystal X-ray diffraction analysis. The
structure contains square-pyramidal tungsten clusters being linked into infinite [(W5Br8i)Br3aBr22/a-a] chains through shared W-Bra-a-W contacts of adjacent clusters. The structure of the adduct I can be viewed as an intercalation compound composed of double-layers
of cluster chains alternating with mono-layers of SbBr3 molecules. 相似文献
14.
Martin Kckerling 《无机化学与普通化学杂志》1999,625(1):24-30
The boron‐centered mixed‐halide zirconium cluster phases were obtained from reactions of appropriate amounts of NaCl or ACl2 (with A = Ca, Sr, Ba), ZrCl4, ZrI4, Zr (powder), and elemental B in sealed tantalum containers at 800–850 °C. Single crystals of NaZr6Cl10.94(1)I3.06B and Sr0.5Zr6Cl11.34(2)I2.66B have been characterized by X‐ray diffraction at room temperature (cubic, Pa 3, Z = 4, a = 1331.3(1) pm, and a = 1326.2(2) pm, respectively). The Zr6 octahedra in these phases are centered by boron and three‐dimensionally connected by exo‐iodide atoms which bridge simultaneously three octahedra. Six out of the twelve inner chlorides (one symmetry independent site) which bridge the edges of each octahedron, but are not involved in inter‐cluster bridging (according to AZr6Ia–a–a6/2(Cl12–xIx)iB), can be completely substituted by iodide. Such a substitution is not possible for the remaining six inner halides on the second symmetry independent site, because the larger iodide atom on this site would experience strong repulsive forces from short anionic contacts. This gives the phase width of NaZr6Cl12–xI2+xB to x È 6. The size of the voids that cover the cations A limits this structure to members with A = Na, Ca, Sr, and Ba. This structure type requires the existence of two differently sized halide types simultaneously. 相似文献
15.
W6Cl18: New Syntheses, New Structure Refinement, Electronic Structure, and Magnetism Pure W6Cl18 was synthesized after two methods, by oxidizing W6Cl12 with CCl4 in an autoclave, and by reaction of W6Cl12 in a chlorine gas flow. At temperatures above 400 °C and under atmospheric pressure W6Cl18 transforms into W6Cl12. The crystal structure of W6Cl18 was refined after the Rietveld method on X‐ray powder data. The unusual electronic conditions of the 18 electron cluster [W6Cl12]Cl6 are compared with those of the electron‐precise 24 electron cluster [W6Cl8]Cl4. The compound exhibits paramagnetic behaviour with two electrons in antibonding energy levels. 相似文献
16.
Reactions between tungsten halides are discussed along the series of compounds WCl6 → WCl4 → W6Cl12 ↔ W6Cl18 → [W6CCl18]n− ← [W3Cl13]u−, focusing on the two closely related tungsten chloride compounds whose structures compromise the well-known octahedro W6Cl18 cluster and the carbon-centered triprismo W6CCl18 cluster. Both clusters can be regarded as being built by merging two trigonal [W3Cl13]u− units in different ways. Syntheses, structural transformation reactions, and concepts regarding electronic structures are
reported. 相似文献
17.
Following the Reaction of Heteroanions inside a {W18O56} Polyoxometalate Nanocage by NMR Spectroscopy and Mass Spectrometry
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Qi Zheng Dr. Laia Vilà‐Nadal Dr. Christoph Busche Dr. Jennifer S. Mathieson Dr. De‐Liang Long Prof. Dr. Leroy Cronin 《Angewandte Chemie (International ed. in English)》2015,54(27):7895-7899
By incorporating phosphorus(III)‐based anions into a polyoxometalate cage, a new type of tungsten‐based unconventional Dawson‐like cluster, [W18O56(HPIIIO3)2(H2O)2]8?, was isolated, in which the reaction of the two phosphite anions [HPO3]2? within the {W18O56} cage could be followed spectroscopically. As well as full X‐ray crystallographic analysis, we studied the reactivity of the cluster using both solution‐state NMR spectroscopy and mass spectrometry. These techniques show that the cluster undergoes a structural rearrangement in solution whereby the {HPO3} moieties dimerize to form a weakly interacting (O3PH???HPO3) moiety. In the crystalline state the cluster exhibits a thermally triggered oxidation of the two PIII template moieties to form PV centers (phosphite to phosphate), commensurate with the transformation of the cage into a Wells–Dawson {W18O54} cluster. 相似文献
18.
Tobias Meißner Ralf Bergmann Joachim Oswald Katrin Rode Holger Stephan Wolfgang Richter Harald Zänker Werner Kraus Franziska Emmerling Günter Reck 《Transition Metal Chemistry》2006,31(5):603-610
The Keggin type polyoxotungstate [Ti2W10PO40]7− forms stable associates with the biopolymer chitosan in the nanometer size range. The cluster compound crystallizes from
aqueous solution as K4H3[Ti2W10PO40] · 15H2O having a tetragonal structure. Both, the cluster compound and the chitosan/[Ti2W10PO40] associates show a high hydrolytic stability at pH 7.4. The associates formed between the cluster anion [Ti2W10PO40]7− with the polyaminosaccharide chitosan have been characterized by photon correlation spectroscopy, scanning electron microscopy,
filtration, centrifugation and zeta potential measurements. The size of the associates formed is in the range of ca. 5×101 to 5×102 nm. These particles have a defined stoichiometry with 5–6 cluster anions bound per molecule chitosan. The isoelectric point
determined by zeta potential measurements was found for a cluster anion to chitosan molar ratio of 5.5, indicating the charge
neutralization between protonated chitosan and [Ti2W10PO40]7− anions. Cellular uptake studies with [Ti2W10PO40]7− using tumor cell lines FaDu (human squamous carcinoma) and HT-29 (human adenocarcinoma) showed that the tungsten amount inside
the cells is remarkably enhanced in the presence of chitosan. 相似文献
19.
Assembly of Tungsten‐Oxide‐Based Pentagonal Motifs in Solution Leads to Nanoscale {W48}, {W56}, and {W92} Polyoxometalate Clusters
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Cai‐Hong Zhan Dr. Ross S. Winter Qi Zheng Dr. Jun Yan Dr. Jamie M. Cameron Dr. De‐Liang Long Prof. Dr. Leroy Cronin 《Angewandte Chemie (International ed. in English)》2015,54(48):14308-14312
We report an approach to synthesize molecular tungsten‐oxide‐based pentagonal building blocks, in a new {W21O72} unit, and show how this leads to a family of gigantic molecular architectures including [H12W48O164]28? {W48}, [H20W56O190]24? {W56}, and [H12W92O311]58? {W92}. The {W48} and {W56} clusters are both dimeric species incorporating two {W21} units and the {W56} species is the first example of a molecular metal oxide cluster containing a chiral “double‐stranded” motif which is stable in solution as confirmed by mass spectrometry. The {W92} anion having four {W21} units is one of the largest transition metal substituted isopolyoxotungstates known. 相似文献
20.
Giant Hollow Heterometallic Polyoxoniobates with Sodalite‐Type Lanthanide–Tungsten–Oxide Cages: Discrete Nanoclusters and Extended Frameworks
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Lu Jin Dr. Xin‐Xiong Li Yan‐Jie Qi Ping‐Ping Niu Prof. Dr. Shou‐Tian Zheng 《Angewandte Chemie (International ed. in English)》2016,55(44):13793-13797
The first series of niobium–tungsten–lanthanide (Nb‐W‐Ln) heterometallic polyoxometalates {Ln12W12O36(H2O)24(Nb6O19)12} (Ln=Y, La, Sm, Eu, Yb) have been obtained, which are comprised of giant cluster‐in‐cluster‐like ({Ln12W12}‐in‐{Nb72}) structures built from 12 hexaniobate {Nb6O19} clusters gathered together by a rare 24‐nuclearity sodalite‐type heterometal–oxide cage {Ln12W12O36(H2O)24}. The Nb‐W‐Ln clusters present the largest multi‐metal polyoxoniobates and a series of rare high‐nuclearity 4d‐5d‐4f multicomponent clusters. Furthermore, the giant Nb‐W‐Ln clusters may be isolated as discrete inorganic alkali salts and can be used as building blocks to form high‐dimensional inorganic–organic hybrid frameworks. 相似文献