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1.
By using tridentate ligand 4-(3-pyridinyl)-1,2,4-triazole (pytrz), cage-like complexes of {[Cu(mu2-pytrz)2](ClO4)(SO4)0.5C2H5OH.0.25 H2O}6 (1), {[Cu3(mu3-pytrz)4(mu2-Cl)2(H2O)2](ClO4)2Cl(2).2 H2O}n (2), and {[Cu3(mu3-pytrz)3(mu3-O)(H2O)3](ClO4)2.5(BF4)(1.5)5.25 H2O}n (3) have been synthesized with different copper(II) salts. Complex 1 represents the second example of a M6L12 metal-organic octahedron with an overall Th symmetry. Complex 2 is constructed from a 3(8) cage-building unit (CBU) and each CBU connects six neighboring cages to give the first 3D metal-organic framework (MOF) based on octahedral M6L12. Complex 3 is built from Cu24(pytrz)12 CBUs with the trinuclear copper clusters serving as second building units (SBUs) and decorating each corner of the M24L12 polyhedron. The Cu24(pytrz)12 building unit is linked by extra ligands to give an extended 3D framework that has the formula Cu24(pytrz)24 and possesses a CaB6 topology. The mixed anions ClO4- and BF4- in 3 are both included in the inner cavity of the cage and can be completely exchanged by ClO4- through the open windows of the cage, as evidenced by the crystal structure of the 3D MOF {[Cu3(mu3-pytrz)3(mu3-O)(H2O)3](ClO4)(4)4.5 H2O}n (4). Complex 4 can also be synthesized when employing 1 as a precursor in an extensive study of the anion-exchange reaction. This represents the first successful conversion of a discrete cage into a 3D coordination network based on a cage structure. Complex 2 remains invariable during anion-exchange reactions because uncoordinated Cl- ions are located in the comparatively small inner cavity.  相似文献   

2.
Two new isostructural 1-D lanthanide coordination polymers, {[Ln(2,4-dcp)3(phen)] n [(Ln?=?Eu (1); Tb (2)], [2,4-dcp?=?2,4-dichlorophenoxyacetate, phen?=?1,10-phenanthroline], were obtained under hydrothermal conditions and characterized by IR spectroscopy, elemental analyses, thermogravimetry analyses, powder X-ray diffraction, and single-crystal X-ray diffraction. Both structures exhibit similar 1-D infinite chains with a {Ln2(2,4-dcp)6(phen)2} dimeric repeat unit, with lanthanides in an eight-coordinate environment. The results of thermal analysis indicate that 1 and 2 are quite stable to heat. 3-D fluorescence spectra of 1 and 2 were detected at room temperature under excitation and the emission wavelengths of 250–460?nm and 420–750?nm with the same interval of 5?nm, respectively. Interestingly, 1 and 2 possess longer fluorescence lifetimes than other complexes (τ?=?1.61?ms for 1 at 611?nm; 1.79?ms for 2 at 543?nm).  相似文献   

3.
Four novel lanthanide coordination polymers [Pr(mal)(OH)(bipy) · 2H2O]n (1), {[Dy1(SBA)3(H2O)2][Dy2(SBA)3(H2O)2] · 4H2O}n (2), {[Tb(OHnic)(Onic)(H2O)5 · (OHnicH)] · H2O}n (3) and {[Sm(OHnic)(Onic)(H2O)5 · (OHnicH)] · H2O}n (4) (Hmal = maleic acid, HSBA = 4-sulfobenzoic acid, OHnicH = 6-hydroxynicotinic acid and bipy = 2,2′-bipyridine) have been synthesized and determined by single crystal X-ray diffraction. Complex 1 is a 1-D helical chain with seven-coordinated praseodymium centers. Complex 2 forms 1-D chain-like molecular structure containing two crystallographically unique dysprosium centers, the Dy1 center is seven-coordinated while Dy2 is eight-coordinated. The isomorphous complexes 3 and 4 exhibit an unprecedented 1-D chain-like polymeric structure through hydroxyl oxygen atoms of bridging Onic2− anions linking up the neighboring central ions, and there exist three types of 6-OHnicH ligands in the structural unit which is rare for lanthanide carboxylate complexes. The photophysical properties of these complexes were studied using ultraviolet absorption spectra, fluorescence excitation and emission spectra.  相似文献   

4.
利用水热法合成了2种新的双咪唑及二元羧酸配体镉配合物[Cd(sdc)(bipe)]·H_2O(1)和[Cd(bpdc)(bipe)(H_2O)](2)[bipe=bis(4-imidazolphenoxy)ethane,H_2sdc=4,4’-sulfonyldibenzoic acid,H_2bpdc=biphenyl-4,4’-dicarboxylic acid].通过元素分析、红外光谱(IR)、X射线单晶衍射和热重分析(TG)等方法对其进行表征,并测试了2种化合物的荧光性质.化合物1展示了一个具有{4~4·6~2}拓扑的(4,4)-连接的sql二维空间网络结构,配体与金属间荷移跃迁化合物2显示了一个具有(4~(12)·6~3)的六连接pcu网状拓扑结构.荧光测试结果显示,配体与金属间发生的荷移跃迁使得化合物1和2的荧光发射峰与配体bipe相比明显发生了红移.  相似文献   

5.
Four new sodium complexes of phenolate and bisphenolate ligands have been synthesized and characterized by NMR spectroscopy and X-ray crystallography to study their coordination chemistry. The monoanionic tridentate [ONN] phenolate ligand gave a dimeric compound [Na2L2] (2), which crystallized in the orthorhombic crystal system, where the sodium ions have four coordination environments. The dianionic tridentate [ONO] phenolate ligand gave a dimeric [Na2(LIH)2] (4) compound in the tetragonal crystal system. The sodium ions Na(1) and Na(1?) are four-coordinate both having a tetrahedral geometry with the O–Na–O angle being ca. 93°, the O^N^O ligand string comprising a tridentate ligand. Interestingly, despite the steric bulk of N(SiMe3)2, a mixture of compounds [NaL] (2) and NaN(SiMe3)2 was isolated as a dimeric structure [Na2L(N(SiMe3)2)]2 (5) crystallized in the monoclinic crystal system. Na(1) is four-coordinate bonding to the phenolic oxygen atom and two N atoms of the ligand L and the N of the N(SiMe3)2 ligand. The coordination around Na(1) is tetrahedrally distorted square planar with the ‘cis’ angles ranging from 75.11(4) to 117.40(5)° and the ‘trans’ angles being 140.87(4) and 154.82(5)°. Na(2) is three-coordinate, bonding to the two phenolate oxygen atoms and the N atom of the N(SiMe3)2 ligand. Na(2), however, is not coplanar with these atoms being displaced 0.42 Å from it. The coordination chemistry for 5 is very intriguing as the sodium ions have mixed four- and three-coordination numbers, probably due to the steric hindrance of the silylamide groups.  相似文献   

6.
Two novel phosphonate compounds (H2L)·Hphen (1) and [Ca(HL)(H2O)]n·3.5nH2O (2) (L = N(CH2PO3H)33?) were synthesized under hydrothermal conditions. Compound 1 features a chain structure in the ac plane, where HL2? anions are interconnected through sharing hydrogen ions to form a 1D zigzag type. Compound 2 features a layered structure in the ab plane, which has inorganic calcium cores with the organic part of the phosphonate anions being encircling the cores through coordination actions. The free water molecules can form hydrogen bonds with the coordinated water molecules and phosphonate oxygen atoms, which are able to link the adjacent layers to generate a 3D network structure. In addition, the thermal stability and photoluminescence properties were also studied.  相似文献   

7.
Two coordination polymers, [Ba(H2L)(H2O)]n·nH2O (1) and [La(HL)(H2O)]n·nH2O (2) (Na2H2L = 4,5-dihydroxy-1,3-benzenedisulfonic acid disodium salt), have been synthesized under hydrothermal conditions. The central metal ions are nine-coordinate with distorted tricapped trigonal prismatic arrangements. Compounds 1 and 2 have 3-D metal–organic framework (MOF) structures which are created by 2-D inorganic layers [Ba2S2O5]n and [La2S2O5]n through organic phenyl moieties of HL3? linkages. The inorganic layers and organic pillars are alternately arranged to generate the 3-D pillared-layered open frameworks with (411, 64) topologies. Results of fluorescence measurements reveal that two decayed emission bands centered at 435 and 408 nm may be caused by interactions of the ligands and the metal ions. The respective luminescence emission peaks appear at different wavelengths and intensities, which can be affected by the metal ions.  相似文献   

8.
Coordination polymers of CuII and NiII with 3-pyridin-3-yl-benzoic acid (3,3-Hpybz), {[Cu(3,3-pybz)2(CH3OH)]·(DMF)} n (1) and {[Ni(3,3-pybz)2(H2O)]?·?(H2O)} n (2), were synthesized and characterized by single-crystal X-ray diffraction, thermogravimetric analyses, elemental analysis, and IR spectroscopy. In 1, CuII ions are linked by paired 3,3-pybz ligands to generate an in?nite 1-D double-strand chain. However, NiII ions in 2 are linked by the 3,3-pybz to form a 2-D corrugated network with a simple (4,4) topology; these 2-D layers are further enlarged to form the final 3-D supramolecular edifice via strong aromatic π–π stacking interactions and O–H?···?O hydrogen bonds. Magnetic properties of 1 and 2 have also been investigated.  相似文献   

9.
10.
The deprotonated form of the ligands pyrazine-2,3-diselenol (pds) and pyrazine-2,3-dithiol (pdt) react with Cu(ClO(4))(2).6 H(2)O to form different Cu(III) complexes Na[Cu(III)(pds)(2)].2 H(2)O (1), Li[Cu(III)(pds)(2)].3 H(2)O (2), and Na[Cu(III)(pdt)(2)].2 H(2)O (4) depending on the countercation compound used as deprotonating agent (NaOH, LiOH). Two other Cu(III) complexes were obtained by replacement of the alkali metal cations with tetrabutylammonium (TBA(+)), namely, TBA[Cu(III)(pds)(2)] (3), and TBA[Cu(III)(pdt)(2)] (5). All complexes were characterized by (1)H and (13)C NMR and IR spectroscopy, electronic absorption, elemental analysis, cyclic voltammetry (CV), and X-ray crystallography. Electrical conductivity measurements on single crystals show that these salts exhibit insulating behavior. The crystal structure of these species revealed a lateral coordination capability of the N atoms of the pyrazine ring of both pds and pdt ligands towards the alkali metal ions, which leads to the build up of a net of coordinative bonds, hydrogen bonds, and contacts that result in the final 3D structure. Two parameters control the crystal engineering of the final 3D structures: the nature of the alkali metal countercation and the nature of the chalcogen atom (Se/S), which allow fine-tuning of complex 3D crystal lattice. Density functional calculations were performed on the [Cu(pds)(2)] and [Cu(pdt)(2)] systems to investigate the electronic structure of the complexes and understand their electronic and electrochemical behavior by studying the frontier molecular orbitals. This study also reveals whether the redox processes take place on the ligands or on the metal center, a question under continuous discussion in the literature.  相似文献   

11.
Two novel trinuclear cluster-based coordination polymers {[M3(dip)(AcO)6]·(X)}n (1, M = Cu, X = CH3OH; 2, M = Co, X = 2H2O) (dip is 2,6-Di-imidazol-1-yl-pyridine), have been synthesised and structurally determined by single crystal X-ray diffraction, element analysis. Crystallographic unit of 1 consists of three Cu(II), six acetic ions, one dip ligand and one methanol molecule, which formed 1D chain through acetic bridges. The 1D chain further constructed 2-D network through dip ligand bridge which formed 3-D network through π···π interaction. Crystallographic unit of 2 consists of three Co(II), six acetic ions, one dip ligand and two water molecules. The trinuclear unit further formed a dimmer through dip ligand bridge which constructed 1-D through dip ligand bridge. The 1D chain further constructed 2-D network through π···π interaction. IR and UV–vis spectrum properties of 1 and 2 were studied. In addition, Hirshfeld surface analysis was also studied for 1.  相似文献   

12.
Two new 4d-4f Ln-Ag heterometallic coordination polymers, {[Ln3Ag5(IN)10(H2O)7]·4(ClO4)·4(H2O)}n (Ln=Eu (1) and Sm (2), HIN=isonicotinic acid), have been synthesized under hydrothermal conditions by reactions of Ln2O3, AgNO3, HIN and HClO4, and characterized by elemental analysis, IR, thermal analysis and single-crystal X-ray diffraction. It is proved that HClO4 not only adjusts the pH value of the reaction mixture, but also acts as anion template. The structure determination reveals that 1 and 2 are isostructural and feature a novel two-dimensional (2D) layered hetrometallic structure constructed from one-dimensional Ln-carboxylate chains and pillared Ag(IN)2 units. The 2D layers are further interlinked through Ag?Ag and Ag?O(ClO4) multiple weak interactions, which form a rare Ag-ClO4 ribbon in lanthanide-transition metal coordination polymers, to give rise to a three-dimensional supramolecular architecture. Moreover, the luminescent properties of these two compounds have also been investigated at room temperature.  相似文献   

13.
Two new polyoxometalate-based coordination polymers have been synthesized at different pHs under identical hydrothermal conditions, (Hbib)[Cu2(bib)2(PMo12O40)] (1) and (Hbib)2[Cu(bib) (PMo12O40)]·2H2O (2) (bib = 4-bis(imidazol-1-yl) benzene). Their structures were determined by single crystal X-ray diffraction analyses and characterized by routine methods. When the pH was adjusted to 2.0???2.5, 1 was obtained, which exhibits a 1-D rail-like chain. Compound 2 was obtained at pH of 2.5???3.2 and exhibits a 2-D layer with (44) sql net. The pH of the reaction plays a key role in the assembly of the polyoxometalate-based coordination polymer. The electrochemical experiments indicate that 2-based carbon paste electrode possesses high catalytic efficiency and high stability towards reduction of iodate and oxidation of ascorbic acid.  相似文献   

14.
Halogenated carbaborane ions [CB(11)H(6)X(6)](-) in which X=Cl or Br have been combined with the host molecule cyclotriveratrylene (CTV) and Group 1 metal cations to give crystalline materials. The complexes [Na(ctv)(H(2)O)(CB(11)H(6)X(6))](CF(3)CH(2)OH) feature chiral Na-CTV coordination chains with complexation of the [CB(11)H(6)X(6)](-) ion by the Na(+) ion, together with the CTV molecular cavity. The coordination chains are hydrogen bonded together to give a puckered two-dimensional hexagonal grid structure. [K(ctv)(CB(11)H(6)Cl(6))(CF(3)CH(2)OH)(0.5)] is essentially isostructural. Complexes [Rb(ctv)(CB(11)H(6)Br(6))(H(2)O)] and [Cs(ctv)(CB(11)H(6)X(6))(CH(3)CN)] are coordination polymers with related distorted hexagonal grid structures. Use of N,N'-dimethylformamide (DMF) as a solvent results in an entirely different type of assembly, with [Na(2)(dmf)(4)(H(2)O)(2)(ctv)][(dmf)(0.5)(ctv)][CB(11)H(6)Br(6)](2) showing unusual [Na-mu-(dmf)-Na] bridges, and once again forming a distorted hexagonal coordination polymer.  相似文献   

15.
Two new compounds {[Ln2(1,2-pda)3(H2O)2]·?2H2O} n (1,2-H2pda?=?1,2-phenylenediacetic acid, Ln?=?Tb, 1; Ho, 2) were prepared by hydrothermal reaction and characterized by X-ray crystallography. The Ln3+ is nine-coordinate by eight oxygen atoms of six 1,2-pda ligands and one oxygen of water. Ln3+ ions are bridged by 1,2-pda ligands via bridging/chelating-bridging pentadentate and chelating-bridging/chelating-bridging hexadentate coordination to form 3-D framework structures. Complex 1 emits strong green fluorescence corresponding to 5D4???7Fj (j?=?6–3) transitions of the Tb3+.  相似文献   

16.
Two new series of neutral oxamato-bridged heterobimetallic chains of general formula [MCu(L(x))(2)] m DMSO (m=0-4) (L(1)=N-2-methylphenyloxamate, M=Mn (1 a) and Co (1 b); L(2)=N-2,6-dimethylphenyloxamate, M=Mn (2 a) and Co (2 b); L(3)=N-2,4,6-trimethylphenyloxamate, M=Mn (3 a) and Co (3 b)) have been prepared by reaction between the corresponding anionic oxamatocopper(II) complexes [Cu(Lx)2](2-) with Mn(2+) or Co(2+) cations in DMSO. The crystal structures of [CoCu(L2)2(H2O)2] (2 b') and [CoCu(L3)2(H2O)2]4 H2O (3 b') have been solved by single-crystal X-ray diffraction methods. Compounds 2 b' and 3 b' adopt zigzag and linear chain structures, respectively. The intrachain Cu...Co distance through the oxamate bridge is 5.296(1) A in 2 b' and 5.301(2) A in 3 b', while the shortest interchain Co...Co distance is 5.995(5) A in 2 b' and 8.702(3) A in 3 b', that is, the chains are well isolated in the crystal lattice due to the presence of the bulky methyl-substituted phenyl groups. Although both Mn(II)Cu(II) and Co(II)Cu(II) chains exhibit ferrimagnetic behaviour with moderately strong intrachain antiferromagnetic coupling (-J(Mn,Cu)=24.7-27.9 cm(-1) and -J(Co,Cu)=35.0-45.8 cm(-1); H= Sigma -J(M,Cu)S(M,i)S(Cu,i)), only the Co(II)Cu(II) chains show slow magnetic relaxation at low temperatures (T(B)<3.5 K), which is characteristic of single-chain magnets (SCMs) because of the high magnetic anisotropy of the Co(II) ion. The blocking temperatures T(B) along this series of chains vary according to the steric hindrance of the aromatic substituent of the oxamate ligand in the series L(1)相似文献   

17.
Xiao J  Liu BY  Wei G  Huang XC 《Inorganic chemistry》2011,50(21):11032-11038
Three cupric coordination assemblies [Cu(btca)(H(2)O)(2)] (1), [Cu(btca)(H(2)O)(3.5)](8)·16H(2)O (2), and [Cu(2.5)(btca)(1.5)(Hbtca)(0.5)(μ-Cl)(0.5)(μ(3)-OH)(H(2)O)]·H(2)O (3) have been solvothermally synthesized by cupric salts and a bifunctional ligand benzotriazole-5-carboxylic acid (H(2)btca) in different solvent medium. These complexes were structurally characterized by X-ray diffraction analyses and further identified by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD), and thermogravimetric analyses (TGA). Single crystal structural analysis shows that these coordination compounds assembled by the almost same reactants present diverse dimensional crystal structures, wherein 1 possesses two-dimensional (2D) layers with (4.8(2)) topology, the zero-dimensional (0D) neutral metallomacrocycle with flat octagonal geometry in 2 connects each other through hydrogen bonding to extend to be a three-dimensional (3D) nanotubular network, and 3 exhibits 3D framework with 1D honeycomb channels constructed by the strip-shaped chains containing [Cu(5)(μ(3)-OH)(2)(btca)(4)](-) pentaclusters bridging to the adjacent Cu(6)(btca)(12)(6-) cages. The diversity of these structures mainly stems from the versatile coordination modes of the anionic ligand in each compound, especially the 1,2,3-triazolate group: bidentate μ(1,2) bridging mode in 1, bidentate μ(1,3) bridging mode in 2, and tridentate μ(1,2,3) bridging mode in 3, respectively. Furthermore, the magnetic properties of 1-3 have been investigated as well.  相似文献   

18.
New homo- and heterometallic, hexa- and pentanuclear complexes of formula {[Cu2(mpba)2(H2O)F][Cu(Me5dien)]4}(PF6)(3).5H2O (1), {[Cu2(Me3mpba)2(H2O)2][Cu(Me5dien)]4}(ClO4)(4).12H2O (2), {[Cu2(ppba)2][Cu(Me5dien)]4}(ClO4)4 (3), and [Ni(cyclam)]{[Cu2(mpba)2][Ni(cyclam)]3}(ClO4)(4).6H2O (4) [mpba=1,3-phenylenebis(oxamate), Me3mpba=2,4,6-trimethyl-1,3-phenylenebis(oxamate), ppba=1,4-phenylenebis(oxamate), Me5dien=N,N,N'N' ',N' '-pentamethyldiethylenetriamine, and cyclam=1,4,8,11-tetraazacyclotetradecane] have been synthesized through the use of the "complex-as-ligand/complex-as-metal" strategy. The structures of 1-3 consist of cationic CuII6 entities with an overall [2x2] ladder-type architecture which is made up of two oxamato-bridged CuII3 linear units connected through two m- or p-phenylenediamidate bridges between the two central copper atoms to give a binuclear metallacyclic core of the cyclophane-type. Complex 4 consists of cationic CuII2NiII3 entities with an incomplete [2x2] ladder-type architecture which is made up of oxamato-bridged CuIINiII and CuIINiII2 linear units connected through two m-phenylenediamidate bridges between the two copper atoms to give a binuclear metallacyclophane core. The magnetic properties of 1-3 and 4 have been interpreted according to their distinct "dimer-of-trimers" and "dimer-plus-trimer" structures, respectively, (H=-J(S1A.S3A+S1A.S4A+S2B.S5B+S2B.S6B)-J'S1A.S2B). Complexes 1-4 exhibit moderate to strong antiferromagnetic coupling through the oxamate bridges (-JCu-Cu=81.3-105.9 cm-1; -JCu-Ni=111.6 cm-1) in the trinuclear and/or binuclear units. Within the binuclear metallacyclophane core, a weak to moderate ferromagnetic coupling (J'Cu-Cu=1.7-9.0 cm-1) operates through the double m-phenylenediamidate bridge, while a strong antiferromagnetic coupling (J'Cu-Cu=-120.6 cm-1) is mediated by the double p-phenylenediamidate bridge.  相似文献   

19.
20.
Four tetrahydrofuran-2,3,4,5-tetracarboxylato bridged copper(II) coordination polymers with alkali metals, Na2[Cu(H2O)(THFTC)]·5H2O 1, K2[Cu3(H2O)2(THFTC)2]·9H2O 2, Rb2[Cu3(H2O)2(THFTC)2]·6H2O 3 and Cs2[Cu3(H2O)2(THFTC)2]·6H2O 4 (H4THFTC = tetrahydrofuran-2,3,4,5-tetracarboxylic acid) were prepared from reactions of Cu(NO3)2·3H2O, tetrahydrofuran-2,3,4,5-tetracarboxylic acid and alkali hydroxide or carbonate at pH 5.0–6.0 under ambient conditions. Compound 1 features 2D (33·43·54) topological layers generated from six-coordinated Cu2+ cations interlinked by (THFTC)4− anions, and the resulting layers are ecliptically stacked along [1 0 0] direction to form lozenge-shaped and octagonal channels filled with Na+ ions and lattice H2O molecules. In 2–4, both penta- and hexa-coordinated copper(II) ions are bridged by tetracarboxylate anions to form negatively charged 2D layers formulated as 2[Cu(H2O)2L3/2]2− with the corresponding alkali metal cations (K+, Rb+ or Cs+ ions) and hydrogen bonded lattice H2O molecules sandwiched between them. Additionally, the results about i.r. spectroscopic, thermal characterizations and magnetic properties are presented.  相似文献   

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