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1.
Three cadmium coordination polymers derived from the dianions of (4-carboxymethoxy-naphthalen-1-yloxy) acetic acid (LH2) and (4-carboxymethoxy-2,3-bis-arylsulfanyl naphthalene-1-yloxy) acetic acid (L1H2), in which the dianions of the corresponding acids act as a spacer to cadmium nodes, have been prepared and characterized. The coordination polymer of the dianion of (4-carboxy-methoxy-2,3-bis-arylsulfanylnaphthalene-1-yloxy) acetic acid with cadmium is a 3-D coordination polymer, whereas the dimensionality of the coordination polymer of the dianion of (4-carboxymethoxy-naphthalen-1-yloxy) acetic acid is dependent on the ancillary ligand. The presence of the chelating ligand 1,10-phenanthroline gave a 1-D polymer of the dicarboxylate anion L, but in the absence of a chelating ligand a 2-D coordination polymer encapsulating hexa–aquacadmium(II) ions was obtained. The latter two coordination polymers show fluorescence emission in the solid state.  相似文献   

2.
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   

3.
Two coordination polymers, namely [Cu(L)2]·(NO3)2 (1) and [Co(L)(chdc)]·2H2O (2) [(chdc?=?1,4-cyclohexanedicarboxylate, L?=?1,3-bis-(5,6-dimethylbenzimidazole-1-yl-methylene)-benzene], based on a flexible 5,6-dimethylbenzimidazole ligand have been synthesized and characterized by physico-chemical and spectroscopic methods and single-crystal diffraction. Complex 1 shows a 2D (4,4) network structure linked by L ligands while complex 2 displays a 1D ladder-like chain bridged by L and chdc ligands. The catalytic activities of both complexes for the degradation of methyl orange have been investigated.  相似文献   

4.
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   

5.
Hydrothermal reactions of cadmium(II) or silver(I) salt, NaN3, 4-(imidazol-1-ylmethyl)benzonitrile (IBN) yield three coordination complexes, [Cd(L)2(H2O)2]·3H2O (1), [Cd3(L)5(OH)] (2) and [Ag2(L)2] (3) where HL=1-(5-tetrazolyl)-4-(imidazol-1-ylmethyl)benzene. The crystal structure analysis revealed that 1 has 1D hinged-chain structure containing 24-membered ring with a Cd···Cd intra-chain distance of 13.18 Å, while 2 is 1D ladder-like chain with Cd3O core. However, the complex 3 is a 3D 4-connected framework with Schläfli symbol of (42·63·8)(43·62·8). The L ligand was found to show four different coordination modes in 1-3, as 2-, 3- and 4-connector, respectively. The results indicate that the coordination modes of the ligand and metal centers with different coordination geometry have great influence on the structures of the complexes. In addition, the photoluminescence of the complexes were studied in the solid state at room temperature.  相似文献   

6.
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   

7.
Three new Cu(II)-Ln(III) heterometallic coordination polymers based on two N-heterocyclic carboxylic ligands, {[LnCu(L1)2(L2)(H2O)2]·mH2O} n (Ln = La(1), Nd(2), Gd(3), m = 2 (for 1), 1 (for 2, 3), H2L1 = quinolinic acid, HL2 = nicotinic acid), have been synthesized and characterized. 1 has a two-dimensional (2D) layer structure with a Schl?fli symbol of (44.62), while complexes 2 and 3 are isostructural and have three-dimensional (3D) structures with a Schl?fli symbol of (3.4.5)2(32.42.52.614.74.83.9)(32.63.7) of 3-nodal net. Magnetic investigations suggest that antiferromagnetic coupling exists between NdIII and CuII in 2, while weak ferromagnetic coupling between GdIII and CuII in 3. The difference of magnetic properties between 2 and 3 has been discussed.  相似文献   

8.
A bioinorganic approach into the problem of the isomorphous substitution of calcium(II) by lanthanide(III) ions in biological systems is discussed. Reactions of malonamic acid (H2malm) with CaII and NdIII sources under similar conditions yielded the compounds [Ca(Hmalm)2]n (1), [Nd(Hmalm)2(H2O)2]n(NO3)n (2) and [Nd(Hmalm)2(H2O)2]nCln·2nH2O (3·2nH2O). Their X-ray crystal structure data show that the malonamate(-1) ligand presents two different ligation modes and coordinates through the two carboxylate and the amide-O atoms, thus bridging three CaII ions in 1 and two NdIII ions in 2 and 3·2nH2O. Complex 1 is a 3D coordination polymer based on neutral repeating units, whereas 2 and 3·2nH2O are 1D coordination polymers based on the same cationic repeating unit. Hydrogen bonding interactions further stabilize the 3D framework structure of 1 and assemble the 1D chains of 2 and 3·2nH2O into 3D networks. The three complexes were characterized spectroscopically (IR, far-IR, and Raman) and the thermal decomposition of 2 and 3·2nH2O was monitored by TG/DTA and TG/DTG measurements. Variable-temperature magnetic susceptibility data for 2 are also reported. The bioinorganic chemistry relevance of our results is discussed.  相似文献   

9.
Five novel coordination polymers, [Co(bpb)2Cl2] (1), [Co(bpb)2(SCN)2] (2), [Cd(H4bpb)0.5(dmf)(NO3)2] (3), [Cd2(H4bpb)Br4] (4), and [Hg2(H4bpb)I4] (5) [bpb=N,N′-bis(3-pyridylmethyl)-1,4-benzenedimethyleneimine, H4bpb=N,N′-bis(3-pyridylmethyl)-1,4-benzenedimethylamine], were synthesized and their structures were determined by X-ray crystallography. In the solid state, complex 1 is a 1D hinged chain, while 2 has 2D network structure with the ligand bpb serving as a bridging ligand using its two pyridyl N atoms. The imine N atoms keep free of coordination and bpb acts as a bidentate ligand in both 1 and 2. Complexes 3, 4, and 5 with reduced bpb ligand, i.e. H4bpb, show similar 2D network structure, in which ligand H4bpb serves as a tetradentate ligand. Thermogravimetric analyses for complexes 1-5 were carried out and found that they have high thermal stability. The magnetic susceptibilities of compounds 1, 2 were measured over a temperature range of 75-300 K.  相似文献   

10.
The flexible ditopic ligand 1,2-bis(3-(4-pyridyl)pyrazol-1-yl)ethane (L4Et) displays remarkable versatility in the complexes that it forms with transition metals with products ranging from 1D chains to interpenetrating 3D networks. The L4Et ligand itself crystallises in the space group P21, adopting a helical twist, although it is found in a variety of other conformations in its complexes. Coordination polymers containing the L4Et ligand vary from almost straight, parallel 1D chains of [Ag2(L4Et)2(ClO4)2(DMF)]·DMF (1), through interdigitating helical complexes containing tetrahedral Zn(II), [Zn(NCS)2(L4Et)]·DMF·H2O (2) to 2D sheets of [Cu(L4Et)2(H2O)2](PF6)2·xH2O (3) and the three-fold interpenetrating 3D network of [Co(L4Et)2(NCS)2] (4). The 3D network adopts an unusual 3D 4-connected dmp (65.8) topology. Dimensionality can be limited by the use of chelating co-ligands, demonstrated by the formation of the dinuclear complex [{Cu(py-2,6-CO2)(H2O)}2(L4Et)] (5).  相似文献   

11.
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   

12.
Two coordination polymers, [Co(L1)(IPA] n (1) and {[Ag(L2)(HMIPA)]·H2O} n (2) (H2IPA = isophthalic acid, L1 = 1,2-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene, H2MIPA = 5-methylisophthalic acid, L2 = 1,6-bis(5,6-dimethylbenzimidazol-1-yl)hexane, have been synthesized and characterized by physicochemical and spectroscopic methods, as well as single-crystal X-ray diffraction. In 1, six-coordinated cobalt centers are bridged by L1 and IPA2? ligands to generate a (4,4) two-dimensional layer. However, complex 2 features a 1D chain structure, which is further extended by O–H···O hydrogen bonding interactions into a 2D supramolecular layer with (63) topology. The fluorescence and thermal gravimetric analysis of both complexes were also explored. Furthermore, the complexes 1 and 2 exhibit remarkable catalytic properties for the degradation of methyl orange dyes in a Fenton-like process.  相似文献   

13.
The self-assembly of unsymmetrical tecton 3-nitro-5-(pyridin-4-yl)benzoic acid (HL)with cobalt chloride under hydrothermal conditions affords a new 2D coordination polymer [Co(L)2] n (1, L = 3-nitro-5-(pyridin-4-yl)benzoate), which is characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, powder X-ray diffraction analysis, and single crystal X-ray diffraction. Compound 1 is of the triclinic system, space group P-1 with a = 9.7857(12) Å, b = 10.3417(13) Å, c = 10.8463(13) Å, α = 85.155(2)°, β = 74.785(2)°, γ = 88.962(2)°, V = 1055.4(2) Å3. The crystal structural analysis of complex 1 shows that the cobalt center is six-coordinated in an octahedral geometry by four O atoms from four different L ligands and two N atoms from two different L ligands; the Co(II) cations are bridged by μ3-L into an interesting two-dimensional network structure. It should be pointed out that the thermal analysis results indicate that complex 1 is quite stable up to 420°C.  相似文献   

14.
The synthesis of 1-(3-thienyl)-benzimidazol-2-ones (3 a and4), described in an earlier paper1, has been further investigated. The Na-salt of3 a is converted to a benzimidazolone substituted in position 3 (3 b). Dehydrogenation of the thiophene nucleus of3 a with chloranil yields5 a, which undergoes substitution in position 3 with Cl(CH2)2N(CH3)2 to give5 b. Monochlorination of5 a yields5 c, the structure of which is confirmed by1H-NMR-spectroscopy.5 d is obtained by reaction of the Na-salt of5 c with Cl(CH2)2N(CH3)2.   相似文献   

15.
5-Carboxyl-1-carboxymethyl-2-oxidopyridinium (H2CCOP) and a combination of N-donor ligands, such as 4,4′-bipyridine (4,4′-bipy) and 1,10-phenanthroline (phen) with d10 metal ions Zn(II) and Cd(II) give rise to four coordination polymers, namely, [Zn2(CCOP)(OH)2(H2O)] (1), [Zn(CCOP)(phen)(H2O)]·H2O (2), [Cd(CCOP)(H2O)2]·3H2O (3), and [Cd(CCOP)(H2O)] (4). Polymer 1 features an unusual bilayer motif and forms the final (3,8)-connected 3D topology by hydrogen bonds. Polymer 2 consists of one-dimensional (1D) chains which are further connected with each other via hydrogen bonds to form the final interesting (3,6)-connected rutile network. Polymer 3 is made up of an unusual 2D structure containing cylinder channels in the b axis and features the (4,4)-connected 3D network by hydrogen bonds. Polymer 4 presents an interesting uninodal 4-connected net compared to polymer 3. These four coordination polymers are obtained by evaporation or hydrothermal route and characterized by analytical, spectroscopic, and crystallographic methods. Photoluminescence studies revealed that these four coordination polymers display structure-related fluorescent emission bands (λex = 342 nm) at 361 nm for polymer 1, 404 nm for polymer 2, 367 nm for polymer 3, and 371 nm for polymer 4 in the solid state at room temperature.  相似文献   

16.
Four homochiral coordination polymers incorporating two chiral reduced Schiff base ligands, namely, [Cu(L1)(H2O)]·H2O (1), [Zn2(L2)2] (2), [Co(L2)(H2O)] (3), and [Ni(L2)(H2O)] (4) (H2L1 = N-(4-carboxyl)benzyl-l-alanine, H2L2 = N-(4-carboxyl)benzyl-l-leucine) have been obtained by hydrothermal methods and characterized by physico-chemical and spectroscopic methods. X-ray crystallographic analysis reveals that complex 1 exhibits a chain structure with 1D channels. Complexes 24 all are 3D network structures with 1D channels in which the isobutyl group of the ligand points toward to the channel. Complex 2 displays strong photoluminescent emission in the purple region.  相似文献   

17.
A new series of di- and tri-organotin(IV) compounds with the general formula R4?n SnL n , where R?=?Me (1,2), Et (3), n-Bu (4,5), n-Oct (6), Ph (7) and L?=?(E)-3-(4-methoxyphenyl)-2-(4-chlorophenyl)-2-propenoate, were synthesized by reaction of silver salt of ligand or ligand acid with diorganotin dichloride/oxide and triorganotin chloride in 2:1 and 1:1 molar ratio, respectively. These compounds were characterized by elemental analyses, FT-IR, multinuclear (1H, 13C, 119Sn) NMR and mass spectrometry. The spectroscopic results revealed that all the diorganotin(IV) compounds possess trigonal bipyramidal structures in solution and octahedral geometry in the solid state around the tin atom. A linear polymeric trigonal bipyramidal structure in the solid state and a tetrahedral environment around the tin atom in non-coordinating solvents has been proposed for the triorganotin(IV) compounds. All synthesized compounds were tested in vitro against a number of microorganisms to assess their biocidal activity. These studies revealed that ligand acid and some of its organotin compounds show promising activity against different strains of bacteria and fungi but lowered than reference drugs.  相似文献   

18.
A reaction of Ni(Allyl)2 with bis(2,6-diisopropylphenyl)diazabutadiene gave an imino amide allyl nickel(II) complex (I). Complicated rearrangements of the imino amide ligand in the coordination sphere of complex I spontaneously yielded a paramagnetic Ni(I) ??-allyl complex as a final reaction product. The nickel complexes produced in this system were studied by EPR, IR, and 2D NMR spectroscopy and mass spectrometry. Structure I was examined by X-ray diffraction.  相似文献   

19.
The reaction of zinc(ii) acetate hydrate with pivalic acid (HOOCBut? = HPiv) in air at 100 °C afforded the new 1D coordination polymer {Zn(Piv)2} n (1), in which the metal atoms are in a tetrahedral ligand environment. The thermal behavior of the resulting compound and the sublimation and vaporization processes in the temperature range of 430–550 K were studied by differential scanning calorimetry and thermogravimetric analysis. The structure of compound 1 was determined by X-ray powder diffraction.  相似文献   

20.
Two new coordination polymers, formulated as [Co(L1)(btec)0.5] n (1) and {[Co(L2)(bdc)]·H2O} n (2) (L1 = 1,3-bis(2-methylbenzimidazol-1-ylmethyl)benzene, H2bdc = 1,3-benzenedicarboxylic acid, H4btec = 1,2,4,5-benzenetetracarboxylic acid, L2 = 1,3-bis(benzimidazol-1-ylmethyl)benzene), have been hydrothermally synthesized and characterized by physicochemical and spectroscopic methods as well as single-crystal X-ray diffraction. The cobalt atoms present different environments, with a trigonal pyramidal geometry in 1 and a distorted octahedral configuration in 2. Complex 1 shows a 2D (4,4) network linked by L1 and btec4? anions, giving an uninodal 4-connected sql topology with a point symbol of {42·62}, while complex 2 displays a 1D ladder-like chain structure, which is further assembled into a 3D supramolecular architecture via C–H···π hydrogen bonding interactions. The fluorescence properties of both complexes have been investigated in the solid state.  相似文献   

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