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1.
The hardness of oxo ions (O2?) means that coinage‐metal (Cu, Ag, Au) clusters supported by oxo ions (O2?) are rare. Herein, a novel μ4‐oxo supported all‐alkynyl‐protected silver(I)–copper(I) nanocluster [Ag74?xCuxO12(PhC≡C)50] ( NC‐1 , avg. x=37.9) is characterized. NC‐1 is the highest nuclearity silver–copper heterometallic cluster and contains an unprecedented twelve interstitial μ4‐oxo ions. The oxo ions originate from the reduction of nitrate ions by NaBH4. The oxo ions induce the hierarchical aggregation of CuI and AgI ions in the cluster, forming the unique regioselective distribution of two different metal ions. The anisotropic ligand coverage on the surface is caused by the jigsaw‐puzzle‐like cluster packing incorporating rare intermolecular C?H???metal agostic interactions and solvent molecules. This work not only reveals a new category of high‐nuclearity coinage‐metal clusters but shows the special clustering effect of oxo ions in the assembly of coinage‐metal clusters.  相似文献   

2.
The crystal structure of hexa‐μ‐hydroxo‐do­deca­methylocta‐μ3‐oxo‐do­deca­gallium(III) bis­[tetra­kis­(penta­fluoro­phenyl)­borate(III)] chloro­benzene disolvate dihydrate, [Ga12(CH3)123‐O)8(μ‐OH)6](C24F20B)2·2C6H5Cl·2H2O, is reported. The gallium–oxo–hydroxide dication is located on an inversion center and adopts a cage structure composed of 12 fused Ga3O3 rings and is associated with the hydrate mol­ecules and the [B(C6F5)4]? anions through hydrogen bonds and one O—H?π‐ring interaction. Disordered chloro­benzene solvent mol­ecules are also present in the crystal structure.  相似文献   

3.
Two new intermetallic alkaline‐earth palladium borides, SrPd4B and BaPd4B were synthesised and their physical properties were investigated. The crystal structure of SrPd4B was solved from powder X‐ray diffraction data: new structure type, space group Pnma, a = 6.0014(1) Å, b = 5.5041(1) Å, c = 11.8723(2) Å, RI = 0.065, RP = 0.093. BaPd4B is isostructural with a = 6.0883(1) Å, b = 5.6066(1) Å, c = 12.0050(2) Å, RI = 0.062, RP = 0.097. The relationship of this structure type with the series of derivatives of the CaCu5 type is discussed. Calculated electronic band structures for palladium, Pd3B, SrPd5, SrPd4B and SrPd3B are compared. The role of boron and strontium for the electronic properties is discussed in detail. SrPd4B shows metallic behaviour with a DOS(EF) ≈? 1.7 eV–1 · f.u.–1 at the Fermi level. Magnetic properties, electrical resistivity and specific heat capacity measurements reveal that the two compounds are diamagnetic metallic conductors with low electronic density of states, in agreement, with the electronic structure calculations.  相似文献   

4.
Photosynthetic water oxidation in plants occurs at an inorganic calcium manganese oxo cluster, which is known as the oxygen evolving complex (OEC), in photosystem II. Herein, we report a synthetic OEC model based on a molecular manganese vanadium oxide cluster, [Mn4V4O17(OAc)3]3?. The compound is based on a [Mn4O4]6+ cubane core, which catalyzes the homogeneous, visible‐light‐driven oxidation of water to molecular oxygen and is stabilized by a tripodal [V4O13]6? polyoxovanadate and three acetate ligands. When combined with the photosensitizer [Ru(bpy)3]2+ and the oxidant persulfate, visible‐light‐driven water oxidation with turnover numbers of approximately 1150 and turnover frequencies of about 1.75 s?1 is observed. Electrochemical, mass‐spectrometric, and spectroscopic studies provide insight into the cluster stability and reactivity. This compound could serve as a model for the molecular structure and reactivity of the OEC and for heterogeneous metal oxide water‐oxidation catalysts.  相似文献   

5.
Thio and Amidothio Derivatives of Diphosphorus(IV) Acid Oxothiodiphosphates(IV) with anions [P2OnS6?n]4? (n = 1–5) are formed by steps wise substitution of thio by oxo ligands in hexathiodiphosphate(4–). Oxidative ammonolysis of thianion leads to amidothio derivatives, [P2(NH2)S5]3? and [P2(NH2)2S4]2?.  相似文献   

6.
The reaction of propargylic amines and CO2 can provide high‐value‐added chemical products. However, most of catalysts in such reactions employ noble metals to obtain high yield, and it is important to seek eco‐friendly noble‐metal‐free MOFs catalysts. Here, a giant and lantern‐like [Zn116] nanocage in zinc‐tetrazole 3D framework [Zn22(Trz)8(OH)12(H2O)9?8 H2O]n Trz=(C4N12O)4? ( 1 ) was obtained and structurally characterized. It consists of six [Zn14O21] clusters and eight [Zn4O4] clusters. To our knowledge, this is the highest‐nuclearity nanocages constructed by Zn‐clusters as building blocks to date. Importantly, catalytic investigations reveal that 1 can efficiently catalyze the cycloaddition of propargylic amines with CO2, exclusively affording various 2‐oxazolidinones under mild conditions. It is the first eco‐friendly noble‐metal‐free MOFs catalyst for the cyclization of propargylic amines with CO2. DFT calculations uncover that ZnII ions can efficiently activate both C≡C bonds of propargylic amines and CO2 by coordination interaction. NMR and FTIR spectroscopy further prove that Zn‐clusters play an important role in activating C≡C bonds of propargylic amines. Furthermore, the electronic properties of related reactants, intermediates and products can help to understand the basic reaction mechanism and crucial role of catalyst 1 .  相似文献   

7.
Synthesis and Structural Studies on Molecular Oxovanadium Phosphonates Solvothermal syntheses at 373 K in the system (MePPh3)[VO2Cl2]/ RPO3H2 (R = tBu; Ph)/Template (T= Cl?, HCl, OH?; Br?) /MeCN have lead to the already known compound [(VO)6(tBuPO3)8 ? Cl?] ( 1 ) [1] as well as to [(VO)6(tBuPO3)8 ? T](T: HCl ( 2 ) OH? 3 ), [(VO)6(PhPO3)8 ? Br?]×solv ( 4 ), (Ph3PMe)2[(VO)6(PhPO3)8 ? Cl?]3 ( 5 ) with an identical VPO‐core, and [(V3O5)(VO)4(tBuPO3)8 ? NO3?] ( 6 ) with seven metal centres. The renewed X‐ray structure analysis of 1 produced evidence, that the {V6P8O24}‐core shows some flexibility and belongs to the enantiomorphic point group O (≡ 432). With the structure data from the compounds 1 – 5 a geometric model for the flexible contraction of the {V6P8O24}‐core was developed. The calculation of the diameter of the host shell for different degrees of contraction shows that the {V6P8O24}‐core is always too small to incorporate a nitrate ion. This leads to the formation of [(V3O5)(VO)4(tBuPO3)8 ? NO3?] ( 6 ) which can be derived topologically from 1 . There is no structural similarity between 6 and the seven oxovanadium units containing anion of (Ph4P)2[(V4O7)(V3O5)(PhPO3)6 ? Cl?] [2]. The thermal degradation of 1 in air starts at 590 K with the oxidation of the organic groups followed by the formation of β‐(VO)(PO3)2. Possibly these results offer new ways to use oxovanadium phosphonates as precursors of oxovanadium phosphate catalysts.  相似文献   

8.
Yellow–orange tetraaquabis(3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olato‐κN3)cadmium(II) dihydrate, [Cd(C8HN4O2)2(H2O)4]·2H2O, (I), and yellow tetraaquabis(3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olato‐κN3)cadmium(II) 1,4‐dioxane solvate, [Cd(C8HN4O2)2(H2O)4]·C4H8O2, (II), contain centrosymmetric mononuclear Cd2+ coordination complex molecules in different conformations. Dark‐red poly[[decaaquabis(μ2‐3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olato‐κ2N:N′)bis(μ2‐3‐cyano‐4‐dicyanomethylene‐1H‐pyrrole‐2,5‐diolato‐κ2N:N′)tricadmium] hemihydrate], [Cd3(C8HN4O2)2(C8N4O2)2(H2O)10]·0.5H2O, (III), has a polymeric two‐dimensional structure, the building block of which includes two cadmium cations (one of them located on an inversion centre), and both singly and doubly charged anions. The cathodoluminescence spectra of the crystals are different and cover the wavelength range from UV to red, with emission peaks at 377 and 620 nm for (III), and at 583 and 580 nm for (I) and (II), respectively.  相似文献   

9.
The structures of five metal complexes containing the 4‐oxo‐4H‐pyran‐2,6‐dicarboxylate dianion illustrate the remarkable coordinating versatility of this ligand and the great structural diversity of its complexes. In tetraaquaberyllium 4‐oxo‐4H‐pyran‐2,6‐dicarboxylate, [Be(H2O)4](C7H2O6), (I), the ions are linked by eight independent O—H...O hydrogen bonds to form a three‐dimensional hydrogen‐bonded framework structure. Each of the ions in hydrazinium(2+) diaqua(4‐oxo‐4H‐pyran‐2,6‐dicarboxylato)calcate, (N2H6)[Ca(C7H2O6)2(H2O)2], (II), lies on a twofold rotation axis in the space group P2/c; the anions form hydrogen‐bonded sheets which are linked into a three‐dimensional framework by the cations. In bis(μ‐4‐oxo‐4H‐pyran‐2,6‐dicarboxylato)bis[tetraaquamanganese(II)] tetrahydrate, [Mn2(C7H2O6)2(H2O)8]·4H2O, (III), the metal ions and the organic ligands form a cyclic centrosymmetric Mn2(C7H2O6)2 unit, and these units are linked into a complex three‐dimensional framework structure containing 12 independent O—H...O hydrogen bonds. There are two independent CuII ions in tetraaqua(4‐oxo‐4H‐pyran‐2,6‐dicarboxylato)copper(II), [Cu(C7H2O6)(H2O)4], (IV), and both lie on centres of inversion in the space group P; the metal ions and the organic ligands form a one‐dimensional coordination polymer, and the polymer chains are linked into a three‐dimensional framework containing eight independent O—H...O hydrogen bonds. Diaqua(4‐oxo‐4H‐pyran‐2,6‐dicarboxylato)cadmium monohydrate, [Cd(C7H2O6)(H2O)2]·H2O, (V), forms a three‐dimensional coordination polymer in which the organic ligand is coordinated to four different Cd sites, and this polymer is interwoven with a complex three‐dimensional framework built from O—H...O hydrogen bonds.  相似文献   

10.
A pure inorganic 2D network molybdophosphate, [Mn3Mo12O24(OH)6(HPO3)8(H2O)6]4? ( 1 a ), synthesized through microwave irradiation with the existence of Mn2+ and organic cations and isolated as [(CH3)2NH2]3Na[Mn3Mo12O24(OH)6(HPO3)8(H2O)6] ? 12 H2O ( 1 ), is found to possess highly enhanced performance in lithium‐ion batteries’ anode materials. The molecule shows multielectron redox properties suitable for producing anode materials with a specific capacity of 602 mA h g?1 at 100 mA g?1 after 50 cycles in lithium‐ion batteries, although its specific capacity is the highest among all the reported pure inorganic 2D polyoxometalates to date, the cyclic stability is not that satisfactory. A hybrid nanocomposite of this 2D network and polypyrrole cations effectively reduces the capacity fading in initial cycles, and increases the stability and improves the electrochemical performance of lithium‐ion batteries as well.  相似文献   

11.
A tetranuclear CeIV oxo cluster compound containing the Kläui tripodal ligand [Co(η5‐C5H5){P(O)(OEt)2}3]? (LOEt?) has been synthesized and its reactions with H2O2, CO2, NO, and Brønsted acids have been studied. The treatment of [Ce(LOEt)(NO3)3] with Et4NOH in acetonitrile afforded the tetranuclear CeIV oxo cluster [Ce4(LOEt)4O7H2] ( 1 ) containing an adamantane‐like {Ce42‐O)6} core with a μ4‐oxo ligand at the center. The reaction of 1 with H2O2 resulted in the formation of the peroxo cluster [Ce4(LOEt)44‐O)(μ2‐O2)42‐OH)2] ( 2 ). The treatment of 1 with CO2 and NO led to isolation of [Ce(LOEt)2(CO3)] and [Ce(LOEt)(NO3)3], respectively. The protonation of 1 with HCl, ROH (R=2,4,6‐trichlorophenyl), and Ph3SiOH yielded [Ce(LOEt)Cl3] ( 3 ), [Ce(LOEt)(OR)3] ( 4 ), and [Ce(LOEt)(OSiPh3)3] ( 5 ), respectively. The chloride ligands in 3 are labile and can be abstracted by silver(I) salts. The treatment of 3 with AgOTs (OTs?=tosylate) and Ag2O afforded [Ce(LOEt)(OTs)3] ( 6 ) and 1 , respectively. The electrochemistry of the Ce‐LOEt complexes has been studied by using cyclic voltammetry. The crystal structures of complexes 1 – 5 have been determined.  相似文献   

12.
Two porous metal–organic frameworks (MOFs), [Zn3(L)(H2O)2] ? 3 DMF ? 7 H2O ( MOF‐1 ) and [(CH3)2NH2]6[Ni3(L)2(H2O)6] ? 3 DMF ? 15 H2O ( MOF‐2 ), were synthesized solvothermally (H6L=1,2,3,4,5,6‐hexakis(3‐carboxyphenyloxymethylene)benzene). In MOF ‐ 1 , neighboring ZnII trimers are linked by the backbones of L ligands to form a fascinating 3D six‐connected framework with the point symbol (412.63) (412.63). In MOF‐2 , eight L ligands bridge six NiII atoms to generate a rhombic‐dodecahedral [Ni6L8] cage. Each cage is surrounded by eight adjacent ones through sharing of carboxylate groups to yield an unusual 3D porous framework. Encapsulation of LnIII cations for tunable luminescence and small drug molecules for efficient delivery were investigated in detail for MOF‐1 .  相似文献   

13.
The title compound, bis­[tris­(2,2′‐bipyridine)iron(II)] tetra­aqua­tetra‐μ4‐oxo‐penta­cosa‐μ2‐oxo‐undeca­oxo­iron(III)sodium(I)­dodeca­tungsten(VI) dihydrate, [Fe(C10H8N2)3]2[NaFeW12O40(H2O)4]·2H2O, consists of a dodeca­tungstoferrate(III) framework grafted on to an [Na(H2O)4]+ cation, two complex [Fe(2,2′‐bipy)3]2+ cations (2,2′‐bipy is 2,2′‐bipyridine) and two uncoordinated water mol­ecules per formula unit.  相似文献   

14.
Interaction of ptert‐butylcalix[8]areneH8 (L8H8) with [NaVO(OtBu)4] (formed in situ from VOCl3) afforded the complex [Na(NCMe)5][(VO)2L8H]?4 MeCN ( 1 ?4 MeCN). Increasing [NaVO(OtBu)4] to 4 equiv led to [Na(NCMe)6]2[(Na(VO)4L8)(Na(NCMe))3]2?10 MeCN ( 2 ?10 MeCN). With adventitious oxygen, reaction of 4 equiv of [VO(OtBu)3] with L8H8 afforded the alkali‐metal‐free complex [(VO)4L83‐O)2] ( 3 ); solvates 3 ?3 MeCN and 3 ?3 CH2Cl2 were isolated. For the lithium analogue, the order of addition had to be reversed such that lithium tert‐butoxide was added to L8H8 and then treated with 2 equiv of VOCl3; crystallisation afforded [(VO2)2Li6[L8](thf)2(OtBu)2(Et2O)2]?Et2O ( 4 ?Et2O). Upon extraction into acetonitrile, [Li(NCMe)4][(VO)2L8H]?8 MeCN ( 5 ?8 MeCN) was formed. Use of the imido precursors [V(NtBu)(OtBu)3] and [V(Np‐tolyl)(OtBu)3] and L8H8, afforded [tBuNH3][{V(p‐tolylN)}2L8H]?3 1/2 MeCN ( 6 ?3 1/2 MeCN). The molecular structures of 1 to 6 are reported. Complexes 1 , 3 , and 4 were screened as precatalysts for the polymerisation of ethylene in the presence of cocatalysts at various temperatures and for the copolymerisation of ethylene with propylene. Activities as high as 136 000 g (mmol(V) h)?1 were sometimes achieved; higher molecular weight polymers could be obtained versus the benchmark [VO(OEt)Cl2]. For copolymerisation, incorporation of propylene was 7.1–10.9 mol % (compare 10 mol % for [VO(OEt)Cl2]), although catalytic activities were lower than [VO(OEt)Cl2].  相似文献   

15.
A novel octacobalt‐containing polyoxoniobate, Na6K12[H2Co8O4(Nb6O19)4]?39 H2O, has been prepared by a combination of hydrothermal and diffusion methods. The polyanion [H2Co8O4(Nb6O19)4]18? incorporates a tetrameric assembly of Lindqvist‐type [Nb6O19]8? fragments trapping a {CoII4CoIII4} cluster which comprises a central {CoIII4O4} cubane core, surrounded by another four CoII ions linkers. Furthermore, magnetic measurements show that the compound exhibits antiferromagnetic interactions.  相似文献   

16.
Two new oxo complexes, namely hexa‐μ2‐acetato‐acetato­aquabis­(di‐3‐pyridylamine)di‐μ3‐oxo‐tetra­iron(III) chloride mono­hydrate ethanol 1.25‐solvate, [Fe4(C2H3O2)7O2(C10H9N3)2(H2O)]Cl·1.25C2H6O·H2O, (I), containing a tetra­nuclear [Fe43‐O)2]8+ unit, and 2‐methyl­imidazolium hexa‐μ2‐acetato‐acetatodiaqua‐μ3‐oxo‐triiron(III) chloride dihydrate, (C4H7N2)[Fe3(C2H3O2)7O(H2O)2]Cl·2H2O, (II), with a trinuclear [Fe33‐O)]7+ unit, are presented. Both structures are formed by two well differentiated entities, viz. a compact isolated cluster composed of FeIII ions coordinated to O2− and CH3CO2 anions, and an external group formed by a central Cl ion surrounded by different solvent groups to which the anion is bound through hydrogen bonding. In the case of (I), charge balance cannot be achieved within the groups, so the structure is macroscopically ionic; in the case of (II), in contrast, each group is locally neutral owing to the inter­nal compensation of charges. The trinuclear complex crystallizes with the metal cluster, chloride anion and 2‐methyl­imidazolium cation bisected by a crystallographic mirror plane.  相似文献   

17.
A new class of hexameric Ln12‐containing 60‐tungstogermanates, [Na(H2O)6?Eu12(OH)12(H2O)18Ge2(GeW10O38)6]39? ( Eu12 ), [Na(H2O)6?Gd12(OH)6(H2O)24Ge(GeW10O38)6]37? ( Gd12 ), and [(H2O)6?Dy12(H2O)24(GeW10O38)6]36? ( Dy12 ), comprising six di‐Ln‐embedded {β(4,11)‐GeW10} subunits was prepared by reaction of [α‐GeW9O34]10? with LnIII ions in weakly acidic (pH 5) aqueous medium. Depending on the size of the LnIII ion, the assemblies feature selective capture of two (for Eu12 ), one (for Gd12 ), or zero (for Dy12 ) extra GeIV ions. The selective encapsulation of a cationic sodium hexaaqua complex [Na(H2O)6]+ was observed for Eu12 and Gd12 , whereas Dy12 incorporates a neutral, distorted‐octahedral (H2O)6 cluster. The three compounds were characterized by single‐crystal XRD, ESI‐MS, photoluminescence, and magnetic studies. Dy12 was shown to be a single‐molecule magnet.  相似文献   

18.
Keggin‐type polyoxometalate anions [XM12O40]n? are versatile, as their applications in interdisciplinary areas show. The Keggin anion [CoW12O40]6? turns into an efficient and robust electrocatalyst upon its confinement in the well‐defined void space of ZIF‐8, a metal–organic framework (MOF). [H6CoW12O40]@ZIF‐8 is so stable to water oxidation that it retains its initial activity even after 1000 catalytic cycles. The catalyst has a turnover frequency (TOF) of 10.8 mol O2(mol Co)?1 s?1, one of the highest TOFs for electrocatalytic oxygen evolution at neutral pH. Controlled experiments rule out the chances of formation and participation of CoOx in this electrocatalyic water oxidation.  相似文献   

19.
Three unprecedented 2D architectures made up of sandwich‐type tetra‐metal‐substituted polyoxotungstates and transition‐metal complexes, [Cu(dien)(H2O)]2{[Cu(dien)(H2O)]2‐[Cu(dien)(H2O)2]2[Cu4(SiW9O34)2]}? 5H2O ( 1 ; dien=diethylenetriamine), [Zn(enMe)2(H2O)]2{[Zn(enMe)2]2[Zn4‐ (HenMe)2(PW9O34)2]}?8H2O ( 2 ; enMe =1,2‐diaminopropane), and [Zn(enMe)2‐(H2O)]4[Zn(enMe)2]2{(enMe)2{[Zn‐ (enMe)2]2[Zn4(HSiW9O34)2]}{[Zn‐ (enMe)2(H2O)]2[Zn4(HSiW9O34)2]}}? 13H2O ( 3 ) were hydrothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single‐crystal X‐ray diffraction. Compound 1 consists of anions [Cu4(SiW9O34)2]12? linked by copper complexes into a 2D structure, whereas 2 is constructed from novel inorganic–organic hybrid anions [Zn4(HenMe)2(PW9O34)2]8? linked by zinc complexes into a 2D structure. The most interesting is the unique 2D network 3 , which consists of anions [Zn4(PW9O34)2]10? with two types of bridging groups: zinc complexes and enMe ligands.  相似文献   

20.
The first fully inorganic, discrete gold–palladium–oxo complex [NaAuIII4PdII8O8(AsO4)8]11? has been synthesized in aqueous medium. The combination of single‐crystal XRD, elemental analysis, mass spectrometry, and DFT calculations allowed establishing the structure and composition of the novel polyanion, and UV/Vis studies suggest that it is stable in neutral aqueous media.  相似文献   

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