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1.
The crystal structures of MOFs [Cu(PDA)(Phen)(H2O)]2 · 5H2O (I) and [Cu(PZCA)2(H2O)2] · 2H2O (II) (H2PDA = pyridine-2,6-dicarboxylic acid, Phen = 1,10-phenanthroline, HPZCA = pyrazine-2-carboxylic acid, H2PZDA = pyrazine-2,3-carboxylic acid) have been prepared under hydrothermal conditions. These MOFs have been characterized by element analysis, single-crystal X-ray diffraction, thermogravimetric analyses and IR spectroscopy. 3D frameworks of MOFs I and II are fabricated from zero-dimensional (0D) motifs through hydrogen bonds and π-π interactions. In MOF II, the PZCA ligand comes from in situ decarboxylation of the part of pyrazine-2,3-dicarboxylic acid (H2PZDA). Luminescent emissions bands of MOF I in methanol have been measured at room temperature and it displays selectivity to Zn2+, Cu2+, Pb2+, and Cd2+ ions. Cyclic voltammetry of MOFs I and II showed that the Cu(II/I) couple is irreversible.  相似文献   

2.
Reaction of a macrocyclic copper(II) complex [Cu(L)](ClO4)2 · 3H2O (I) (L = 1,3,10,12,16,19-hexaazatetracyclotetracosane) with a hexapod carboxylate ligand H6TTHA (H6TTHA = 1,3,5-triazine-2,4,6-triamine hexaacetic acid) and a tripod carboxylate ligand H3TATB (H3TATB = 4,4′,4″-S-triazine-2,4,6-triyl-tribenzoic acid) yielded two mononuclear copper(II) complexes [Cu(L)][H4TTHA] · 4H2O (II) and [Cu(L)][HTATB] · 4H2O (III). The complexes I–III have been structurally characterized. The crystal structures of complexes II and III show the copper(II) ion has a distorted pentacoordinate square-pyramidal geometry with two secondary and two tertiary amines from the macrocyclic complex [Cu(L)]2+ and one oxygen atom from the carboxylate ligand group at the axial position. The UV-Vis spectra are utilized to discuss the hydrolysis of the complex II.  相似文献   

3.
A new homonuclear and heterodinuclear pyridine-2,6-dicarboxylate complexes, formulated as (enH2)[Cu(dipic)2]·2.5H2O (1) and [Cu(μ-dipic)2Zn(H2O)5]·2H2O (2) (en = ethylenediamine, dipic = pyridine-2,6-dicarboxylate) were synthesized according the reactions between the three species of copper(II) and zinc(II) nitrate, ethylenediamine and pyridine-2,6-dicarboxylic acid. Complexes have been characterized by the methods of elemental, spectroscopic (IR and UV–Vis), thermal (TG/DTG, DTA) analysis, magnetic measurement and single crystal X-ray diffraction. Correlation coefficient, activation energies, E∗; pre-exponential factor, A; entropies, S∗; enthalpies, H∗ and Gibbs free energies, G∗ of the thermal decomposition reactions have been calculated under the derivations from thermogravimetric (TG) and differential thermogravimetric (DTG) curves, using the Coats–Redfern and Horowitz–Metzger methods. Complex 1 belonged to a six-coordinate behavior with a distorted octahedral geometry around Cu(II), that the structure contains two pyridine-2,6-dicarboxylate species as a tridentate ligands and ethylenediaminium cation as a counter ion as well as 2.5 uncoordinated water molecules. On the other hand complex 2 contains six-coordinated Cu(II) and Zn(II) ions, which are linked by two O atoms of the same carboxyl group from dipicolinic acid. The dipicolinate dianions again behave as tridentate ligands in 2. Two uncoordinated water molecules are also present in the structure. The structure units of 1 and 2 are mutually held by the hydrogen bonds and π?π interactions. There is also a C–O?π interaction in 2. The Cu(II) complexes are connected to one another via O–H?O hydrogen bonds, forming water clusters, which play an important role in the stabilization of the crystal structure. In the water clusters, the water molecules are trapped by the cooperative association of coordination interactions as well as hydrogen bonds.  相似文献   

4.
The homonuclear water-soluble and air stable compounds (dmpH) (H5O2) au][M(pydc)2].0.5H2O (M = Ni(II) (1), Cu(II) (2), Zn(II) (3); pydcH2 = pyridine-2,6-dicarboxylic acid, dipicolinic acid, dmp = 2,9-dimethyl-1,10-phenanthroline) have been prepared by self-assembly synthesis in aqueous solution at room temperature, and characterized by IR, 1H NMR, 13C NMR, elemental analysis and X-ray diffraction single crystal analyses for 1, 2 and 3. The complexes 1–3 represent the isostructural features. Extensive hydrogen bonding interactions involving all aqua ligands, dipicolinate oxygens and lattice water molecules further stabilize the complex units by linking them to form three dimensional polymeric networks. The stoichiometry and stability of the all three complexes in aqueous solution were investigated by potentiometric pH titration.  相似文献   

5.
The coordination polymers [Ag(C4H10N2)]CH3SO3 (I) and [Ag(C4H10N2)]PO2F2 (II) (C4H10N2 is piperazine (Ppz)) are synthesized, and their structures are determined. The crystals of I are monoclinic, space group P21/c, a = 6.280(1) Å, b = 11.781(1) Å, c = 12.112(1) Å, β = 97.21(1)°, V = 889.0(2) Å3, ρcalcd = 2.160 g/cm3, and Z = 4. The crystals of II are orthorhombic, space group Cmca, a = 13.039(1) Å, b = 10.450(1) Å, c = 12.837(1) Å, V = 1749.1(3) Å3, ρcalcd = 2.240 g/cm3, and Z = 8. Structure I contains cationic polymer chains [Ag(Ppz)] + . The silver atom bound to two nitrogen atoms of two Ppz ligands has an almost linear coordination mode (Ag-Naverage 2.197 Å, angle NAgN 161.2(1)°). The structure includes supramolecular layers due to weak interactions Ag…O(CH3SO3). Structure II is built of zigzag polymer chains [Ag(Ppz)]+ and tetrahedral cations PO2F 2 ? . The Ag+ ion has a linear coordination mode (Ag-N 2.220(3) Å, and the NAgN angle is 164.3(2)°). The tetrahedral anions PO2F 2 ? having weak contacts with the silver ions (Ag…O 2.630(3)Å) join the [Ag(Ppz)] + chains into wavy layers.  相似文献   

6.
The Cu(II) complexes [Cu(Tppz)(Dipic)] · 8H2O (I) and [Pb2(Tppz)Cl4] n (II), where Tppz, H2Dipic are 2,3,5,6-tetrakis(2-pyridyl)pyrazine, dipicolinic acid, respectively, have been synthesized and characterized by elemental analyses, IR, cyclic voltammetry, and electronic spectral studies. Solid state structures of both complexes have been determined by single crystal X-ray crystallography. An ORTEP drawing of two complexes shows that the coordination geometry around the metal center is a distorted octahedron. There are extensive conventional intermolecular O-H…O, N-H…O, and weaker C-H…O and C-H…Cl non-classical hydrogen bonds, which cause the stability of the crystal structure. Crystal data for I: monoclinic, space group: C2/c, a = 35.421(3), b = 8.422(6), c = 22.824(8) Å, β = 101.69(2)°, V = 6668(5) Å3, Z = 8. Crystal data for II: triclinic, space group P \(\bar 1\) , a = 7.9534(4), b = 8.8682(5), c = 9.4245(5) Å, β = 95.086(2)°, V = 655.93(6) Å3, Z = 2.  相似文献   

7.
Two new dinuclear copper(II) complexes, Cu2(L1)4(mal)2(H2O)2 (1) (L1 = 5,6-dimethylbenzimidazole, mal = malonate), Cu2(L2)2(pydca)2·4H2O (2) (L2 = 1,5-bis(5,6-dimethylbenzimidazole)pentane, pydca = pyridine-2,6-dicarboxylate) have been synthesized and characterized by elemental analysis, IR, and single-crystal X-ray diffraction. The Cu(II) atoms in 1 and 2 both have square pyramidal coordination geometry. In 1, the two similar mononuclear structures are linked by π–π stacking as well as multiple hydrogen bonding interactions to generate a 2D supramolecular layer, while complex 2 is connected with two different patterns of π–π stacking and hydrogen bonding interactions into a 3D supramolecular network. The catalytic activities of 1 and 2 for the degradation of Congo red have been investigated.  相似文献   

8.
A series of metal-organic frameworks, namely [Ni(PDB)(H2O)]n (1), [Pb(PDB)(H2O)] · (H2O) (2), [Co2(PDB)2(bpy)2(H2O)4] · 4H2O (3) and [Co2(PDB)2(phen)2]n (4) (H2PDB = pyridine-3,5-dicarboxylic acid, bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline), have been synthesized based on pyridine-3,5-dicarboxylate acid and two neutral chelate ligands, with different metal ions such as NiII, CoII and PbII, under hydrothermal conditions. The framework structures of these polymeric complexes have been determined by the X-ray single crystal diffraction technique. In the four complexes, the pyridine-3,5-dicarboxylate acid ligand exhibits diverse coordination modes, which play an important role in the construction of metal-organic frameworks. The thermal analyses of these four complexes have been measured and discussed. In addition, complex 2 shows strong phosphorescent emission at room temperature and the magnetic measurement of the polymer of 4 reveals a typical antiferromagnetic exchange.  相似文献   

9.
The synthesis of the [Cu(H2L)](NO3)2 complex (I) and of a mixed-valent complex [Cu(H2L)Cl]2[CuCl2]Cl·0.5H2O (II), where L is chiral bis(menthane) propylenediaminodioxime. According to the data of single-crystal X-ray diffraction analysis, compounds I and II have ionic structures. In complex cations, the Cu2+ ion coordinates four N atoms of tetradentate chelate ligand, namely, the H2L molecule. The coordination surrounding of the Cu atom in I is a distorted square CuN4, while in II, it is a distorted square pyramid CuN4Cl. The complex anion [CuCl2]? in II has linear structure. The mutual arrangement of oxime groups in H2L corresponds to amphi-configuration of a ligand and therefore, intramolecular hydrogen bond O...H-O are formed in H2L. The complex cations in compound II are joined in dimers through hydrogen bonds Cl...H-O. The values μeff for I and II are equal to 1.82 and 2.82 μB, respectively.  相似文献   

10.
Transition metal complexes of 2-(1-(carboxymethyl)-2-methyl-1H-benzimidazol-3-ium-3-yl)acetate (HL), namely [Co(L)2(H2O)4] · 6H2O (I) and [Cu(L)2(H2O)2] · 4H2O (II), have been synthesized by a hydrothermal procedure and characterized by X-ray crystallography, CIF files CCDC nos. 1007524 (I), 1007525 (II). Both I and II are mononuclear molecules. In I, the Co2+ ion is in octahedral coordiantion environment and surrounded by four O atoms from water molecules and two carboxylate O atoms of two deprotonated ligand (L?) occupied six culmination. While in II, the Cu2+ ion is located in a square-planar geometry, bounded to two aqua O atoms and two carboxylate O atoms from L?.  相似文献   

11.
Three complexes with the formula [Co(Ip)(CuL)(H2O)2] · H2O (I), [Co(Ip)(NiL)(H2O)2] · H2O (II), [Co(CuL)2(Hbtc)(H2O)] (III), (H2Ip = m-isophthalic acid; H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien; H3Btc = 1,3,5-benzenetricarboxylic acid) were synthesized and structurally characterized by elemental analysis, IR and UV spectroscopy. Single-crystal X-ray analyses reveal that the complexes I and II contain neutral heterometallic binuclear CoM (for I and II, M = Cu, Ni, respectively) moieties, and complex III contains discrete neutral trinuclear CoCu2 moieties. The structures of IIII consist of two-dimensional supramolecular architecture formed by strong O-H…O intermolecular hydrogen bonds. Furthermore, the magnetic properties of complex I were investigated and discussed in detail.  相似文献   

12.
New oxamido-bridged binuclear CuII-CuII complexes, [Cu(Oxen)Cu(Bipy)2](ClO4)2 (I) and [Cu(Oxen)Cu(4,4??-Bipy)2(H2O)2](ClO4)2 (II) (Oxen is N,N??-bis(2-aminoethyl)oxamide dianion, Bipy = 2,2??-bipyridine, 4,4??-Bipy = 4,4??-bipyridine), have been constructed and structurally characterized by X-ray crystallography. In these two complexes, each Cu2+ ion is located in a slightly distorted square-pyramidal environment. Complex I is extended to two-dimensional by face-to-face ??-??-stacking with a distance of 3.648 II is raised to one-dimensional by face-to-face ??-??-stacking and intermolecular H-bonding interaction with distances of 3.651 and 2.767 I is also investigated.  相似文献   

13.
Two new bis(5,6-dimethybenzimidazole)-based CoII complexes, Co(pydca)(L)2·2H2O (1) and [Co(bdc)(L)] n (2) (L = 1,3-bis(5,6-dimethylbenzimidazol-1-yl)-2-propanol, H2pydca = pyridine-2,6-dicarboxylic acid, H2bdc = 1,4-benzenedicarboxylic acid) were synthesized and characterized by physicochemical, spectroscopic methods and single-crystal diffraction. The cobalt(II) centers display different environments with distorted square-pyramidal geometry in 1 and a perfect tetrahedral geometry in 2. Complex 1 is a mononuclear structure, which is further assembled into a 3D supramolecular network via strong hydrogen bonding as well as ππ interactions; while complex 2 possesses a 2D corrugated (4,4) network that is further formed into a (3,4,4)-connected network with (62.84)(63)2(64.82)2-3,4,4T25 topology due to classical hydrogen bonds. The fluorescence and catalytic performances of the two complexes for the degradation of methyl orange by sodium persulfate have been investigated.  相似文献   

14.
Two complexes of gallium(III) with adduct ion pair compounds containing pyridine-2,6-dicarboxylic acid and two different Lewis bases are synthesized. The chemical formulae are (dmpH)[Ga(pydc)2]·2H2O, (1) and (bpyH2)1/2(pydcH2)1/2[Ga(pydc)2]·4H2O, (2) where pydc, dmp, and bpy are pyridine-2,6-dicarboxylate, 2,9-dimethyl-1,10-phenanthroline, and 4,4′-bipyridine respectively. The two crystal structures illustrate that the GaIII ion is six-coordinated by two pyridine-2,6-dicarboxylates. Hydrogen bonds as well as other noncovalent interactions such as ion-pairing, C-O...π, C-H...π, and π...π stacking play an important role in the formation of supramolecular systems. Particular attention is given to the molecular geometries and NMR properties of the complexes from the computational point of view. The electronic properties of the complexes are analysed using the parameters derived from the atoms in molecules (AIM) and natural bond orbital (NBO) methodologies at the B3LYP/6-311++G(2d,2p) computational level.  相似文献   

15.
Reactions of Ni(NO3)2 · 6H2O) in EtOH(iso-PrOH) with optically active bis(menthane) ethylene-diaminodioxime (H2L1), pinano-para-menthane ethylenediaminodioxime (H2L2), pinano-para-menthane propylenediaminodioxime (H2L3) and bis(pinane) propylenediaminodioxime (H2L4) were used to synthesize [Ni(H2L1)NO3[NO3 · 2H2O (I), [Ni(HL2)]NO3 (II), [Ni(HL3)]NO3 (III), and [Ni(HL4)]NO3 (IV). X-ray diffraction study of paramagnetic complex Ieff = 3.04 μB and diamagnetic complexes II and III revealed their ionic structures. A distorted octahedral polyhedron N4O2 in the cation of complex I is formed by the N atoms of tetradentate cycle-forming ligand, i.e., the H2L1 molecule, and the O atoms of the NO 3 ? anion acting as a bidentate cyclic ligand. In the cations of complexes II and III, containing a pinane fragment, the coordination core NiN4 has the shape of a distorted square formed on coordination of tetradentate cycle-forming ligands, i.e., anions of the starting dioximes. The structure of diamagnetic complex IV is likely to be similar to the structures of complexes II and III.  相似文献   

16.
The coordination chemistry of a rigid periodinated ligand, 2,3,5,6-tetraiodo-1,4-benzenedicarboxylic acid (H2BDC-I4), with a series of transition metal ions has been explored to afford five new coordination polymers {[M(BDC-I4)(MeOH)4](H2BDC-I4)(MeOH)2} n (M?=?ZnII for 1, CdII for 2, CoII for 3 and MnII for 4) and {[Mn(BDC-I4)(MeOH)4](DMF)} n (5). All these complexes have been characterized by elemental analysis, IR spectroscopy, thermogravimetric (TG) analysis, and X-ray crystallography. Single-crystal X-ray diffraction reveals that complexes 1?C4 are isostructural and have a one-dimensional chain structure. Upon the addition of the solvent DMF, the infinite linear chain array in 4 is converted to a 1-D wave-like chain motif in 5 with a different space group ( $ P\overline{1} $ for 4 and P21/c for 5). The difference between structures 1?C4 and 5 can be attributed to the coordination mode of carboxylate changing from trans to cis fashion. The ZnII and CdII complexes 1 and 2 display similar emissions in the solid state, which essentially are intraligand transitions.  相似文献   

17.
Copper(II) salts were reacted with various quinoline aldehyde chalcogensemicarbazones to yield compounds formulated as Cu(HL)X2 · nH2O (I: HL = quinoline aldehyde thiosemicarbazone (HL1), X = ClO4, n = 2; II: HL = quinoline aldehyde 4-C2H5-thiosemicarbazone (HL1a), X = NO3, n = 0; III: HL = quinoline aldehyde semicarbazone (HL2), X = ClO4, n = 3 and IV: HL = quinoline aldehyde 4-Ph-semicarbazone (HL2a), X = NO3, n = 1). Regardless of the reagent ratio, the products were compounds having the metal: ligand ratio of 1: 1, where the organic ligand was coordinated tridentate in a molecular form. Single-crystal X-ray diffraction showed that, depending on the chalcogen atom in the organic ligand (S or O), the substituent in the 4th position (at the terminal nitrogen atom), and the specifics of the acido ligand, complexes I–IV had appreciably differing molecular structure organizations. The structures of I and III are formed by a 1D charged coordination polymer, ClO 4 ? anions, and water molecules and may be described by the formula [Cu(HL)(H2O)(ClO4)] n (ClO4) n · nH2O. Copper(II) coordination polyhedra in I and II are (4 + 2) and (4 + 1 + 1) tetragonal bipyramids, respectively. In II and IV, the structures are monomeric and can be described as [Cu(HL1a)(NO3)2] with the metal coordination polyhedron shaped as a (4 + 1) tetragonal pyramid in II and as [Cu(HL2a)(H2O)(NO3)](NO3) with the metal coordination polyhedron shaped as a (3 + 2) trigonal bipyramid in IV. The structure of II is built of molecular complexes, each comprising, apart from ligand HL1a, two monodentate coordinated NO 3 ? groups. The oxygen atom of one anion together with the NNS donor atom set of ligand HL1a form the base, and the oxygen atom of the other anion is in the apex of the coordination polyhedron. In IV, the structure is ionic and built of NO 3 ? anions and [Cu(HL2a)(H2O)(NO3)]+ complex cations, where a cationic coordination polyhedron has a trigonal-bipyramidal configuration with organic ligand HL2a positioned along the long edge. The bipyramidal base is made up by the oxygen atoms of the coordinated water molecule and monodentate nitrato group and the nitrogen atom N2 of the azomethyne group.  相似文献   

18.
Four 3d-4f heterometallic complexes, [CuⅡ LnⅢ (bpt) 2 (NO 3 ) 3 (MeOH)] (Ln = Gd, 1; Dy, 2; bptH = 3,5-bis(pyrid-2-yl)-1,2,4- triazole), [CuⅡ 2 LnⅢ 2 (μ-OH) 2 (bpt) 4 Cl 4 (H 2 O) 2 ]·6H 2 O (Ln = Gd, 3; Dy, 4), have been synthesized under solvothermal conditions. X-ray structural analyses reveal that 1 and 2 are isostructural while 3 and 4 are isostructural. In each complex, the copper and gadolinium or dysprosium ions are linked by two triazolate bridges and form a CuⅡ -LnⅢ dinuclear unit. The intramolecular Cu-Ln distances are 4.542, 4.525, 4.545 and 4.538 for 1, 2, 3 and 4, respectively. Two dinuclear CuLn units are bridged by two OH- groups into the zig-zag tetranuclear {CuⅡ 2 LnⅢ 2 } structures with the Ln(Ⅲ) Ln(Ⅲ) distances of 3.742 and 3.684 for 3 and 4, respectively. Magnetic studies show that the antiferromagnetic CuⅡ-LnⅢ interactions occur in 1 (J CuGd = 0.21 cm-1 ) and 2. The antiferromagnetic interaction occurs in complex 3 with J CuGd = 0.82 cm-1 and J GdGd = 0.065 cm-1 , while dominant ferromagnetic interaction occurs in complex 4.  相似文献   

19.
A series of complexes has been synthesized based on pyridine-2,6-dicarboxylate (L1) as the bridging ligand and 5-(4-bromophenyl)-2,4-bipyridine (L2) as the pendant with different metal ions such as NiII, CoII, and CuII, under hydrothermal conditions. In nickel and cobalt complexes [M(L1)(L2)2 · H2O]n (M = Ni2+ or Co2+), the metal ions are bridged by L1 to form 1D coordination zigzag polymeric chains with L2 pendants possessing hexa-coordinated distorted octahedral geometries. While the copper ions are penta-coordinated by L1 and L2 with distorted square pyramidal geometries forming the tetranuclear cluster with the formula [Cu4(L1)4(L2)4] · 2H2O. It has been found that both the structure and magnetic property of these complexes are metal ions dependent. Intramolecular antiferromagnetic interactions were observed in the nickel and cobalt 1D coordination polymers, while ferromagnetic coupling was found in the tetranuclear copper cluster. Density functional theory calculations suggested that the O–C–O bridges of L1 in a basal–apical mode are responsible for intracluster intermetallic ferromagnetic exchange for the tetranuclear copper cluster.  相似文献   

20.
The interaction of the enantiopure (R)- and (S)-1-phenyl-N,N-bis(pyridine-3- ylmethyl)ethanamine ligands, R-L 1 and S-L 1 , with copper(II) chloride followed by addition of hexafluorophosphate resulted in the isolation of the corresponding enantiomeric complexes [Cu(R-L 1 )Cl](PF6) (1), [Cu(S-L 1 )Cl](PF6) (2) and [Cu(S-L 1 )Cl](PF6)??0.5Et2O (3), in which dimerization occurs through two long Cu??????Cl interactions, the ??-chloro bridges being thus strongly asymmetric. The organic ligand is bound to the metal centre via its N3-donor dipyridylmethylamine fragment in a planar fashion, such that each copper centre is in a square planar environment (or distorted square pyramidal with a long axial bond length if the additional interaction is considered). When R,S-L 1 was employed in a parallel synthesis, the similar racemic complex [Cu(R,S-L 1 )Cl](PF6)??0.5MeOH (4) was obtained, in which the L 1 ligands in each dimeric unit have opposite hands. In contrast to the complexes of L 1 , the reaction of Cu(II) chloride with the related ligand, (R)-1-cyclohexyl-N,N-bis(pyridine-3-ylmethyl)ethanamine (R-L 2 ), yielded the mononuclear complex [Cu(R,S-L 2 )Cl2] (5), displaying a distorted square pyramidal coordination geometry. The structure of this product along with its corresponding circular dichroism spectrum revealed that racemisation of the starting R-L 2 ligand has occurred under the relatively mild (basic) conditions employed for the synthesis. A temperature-dependent magnetic studies of the complexes 1, 2 and 5 indicate that a week ferromagnetic interaction is operative in each dicopper core in 1 and 2 with 2J?=?1.2?cm?1. On the other hand, a week antiferromagnetic intermolecular interaction is operative for 5.  相似文献   

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