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1.
The coordination capability of the octaaza 24-membered (L1) and the tetraoxotetraaza 28-membered (L2) macrocycle ligands - with different sizes, nature and number of the donor atoms - has been investigated with nitrate and perchlorate Cd(II) salts. The complexes were prepared in 1:1 and 2:1 Cd:L molar ratio. The characterization by elemental analysis, IR, LSI mass spectrometry, conductivity measurements and 1H NMR spectroscopy, together with the crystal structure of the complexes [CdL1](NO3)2 · 0.5H2O, [CdL1](ClO4)2 and [CdL2(CH3CN)2](ClO4)2 · CH3CN · H2O confirms the formation of mononuclear complexes in all cases. The [CdL1](NO3)2 · 0.5H2O and [CdL1](ClO4)2 present a mononuclear endomacrocyclic structure with the metal ion coordinated by the eight donor nitrogen atoms from the macrocyclic backbone in a square antiprism geometry. The complex [CdL2(CH3CN)2](ClO4)2 · CH3CN · H2O is also mononuclear, but the cadmium ion is in an octahedral environment coordinated by four amine nitrogen atoms from the macrocyclic framework and two nitrogen atoms from two acetonitrile molecules. The ether oxygen atoms from the ligand are not coordinated.  相似文献   

2.
Three palladium(II) complexes have been synthesized, using 3,4-bis(cyanamido) cyclobutane-1,2-dione dianion (3,4-bis(cyanamido)squarate or 3,4-NCNsq2−): [Pd(en)(3,4-NCNsq)] · 1.5H2O (1) (en=1,2-diaminoethane), [Pd(en)(3,4-(NC(O)NH2)sq)] · 0.5H2O (2) and K3Na[Pd2(3,4-(NCN)2sq)4] · 5H2O (3). Complex 1 has been characterized by elemental analysis, IR and 13C NMR spectroscopies. Complexes 2 and 3 have been characterized by single-crystal X-ray diffraction. In complex 2, the unusual hydration of the cyanamido ligand was observed, it proceeds in the coordination sphere of the palladium and leads to a chelating urea squarate ligand. Complex 3 is an anionic dinuclear complex containing four bridging cyanamido squarate ligands. In complexes 2 and 3, the 3,4-NCNsq2− ligand (hydrated or not) is, for the first time, coordinated to the metal atom by the two amido nitrogen atoms, either in a chelating mode (complex 2) or in a bridging mode giving a short Pd ? Pd distance of 2.8866(15) Å (complex 3). Electrochemical studies in acetonitrile and dmf solutions have been performed on complexes 1 and 3.  相似文献   

3.
Cytotoxicity and herpes simplex virus (HSV-1) inhibitory activity of acyclovir (ACV), 9-[(2-hydroxyethoxy)methyl]guanine, and the palladium(II) coordination complex cis-[PdCl2(H2O)(N7-ACV)] · ACV · xH2O have been tested in African green monkey kidney (Vero line) epithelial cell cultures. The N(7) position of ACV represents the preferred binding site to afford a pseudo-chelate N7/O6 Pd(II) complex involving H-bonds with the cis H2O molecule. The Pd(II)-ACV complex has been structurally characterized by FTIR and 1H NMR spectroscopy techniques, chemical composition was measured by elemental analysis, and the thermoanalytical study was performed by TG/DTA. The recognition of secondary ACV molecules by the Pd(II) derivative promotes cooperatively potent HSV-1 inhibitory activity which, in turn, strongly depends on concentration conditions. At the optimal concentration of 10 μM, this complex exhibits antiviral efficiency in vitro, approximately hundred-fold (ca. 1.87 log10) more effective in herpes-infected cells when compared with that of the parent ACV molecules. The molecular-level observation of noticeable modifications caused by the complex on the morphology of the plasmid pBR322 DNA was monitored by AFM, whose mutual interaction evolves to eventually afford DNA condensates upon increasing the period of incubation.  相似文献   

4.
Two palladium(II) complexes, [Pd(phen)(NCCH3)2][O3SCF3]2 (1) and [Pd(phen)(μ-OH)]2[O3SCF3]2 · 2H2O (2) (where phen = 1,10-phenanthroline), have been crystallized following the reaction of Pd(phen)Cl2 with silver triflate, Ag(O3SCF3), in acetonitrile and water, respectively. The structures of both complexes are based on a Pd(phen)2+ metal core, with two acetonitrile molecules binding in a monodentate fashion in complex 1 and two hydroxo bridges holding together two cores to form a dimer in complex 2. Additionally, both complexes present a hydrogen bonded 3-D network involving the triflate anions in 1, and water and triflate anions in 2. Both complexes have been characterized by infrared and 1H NMR spectroscopy and their crystal structures determined by X-ray crystallography.  相似文献   

5.
Four copper(II) complexes containing the reduced Schiff base ligands, namely, N-(2-hydroxybenzyl)-glycinamide (Hsglym) and N-(2-hydroxybenzyl)-l-alaninamide (Hsalam) have been synthesized and characterized. The crystal structures of [Cu2(sglym)2Cl2] (1), [Cu2(salam)2(NO3)2] · H2O (3), [Cu2(salam)2(NO3)(H2O)](NO3) · 1.5H2O (4), [Cu2(salam)2](ClO4)2 · 2H2O (5) show that the Cu(II) atoms are bridged by two phenolato oxygen atoms in the dimers. The sglym ligand bonded to Cu(II) in facial manner while salam ligand prefers to bind to Cu(II) in meridonal geometry. Variable temperature magnetic studies of 3 showed it is antiferromagnetic. These Cu(II) complexes and [Cu2(sglym)2(NO3)2] (2), exhibit very small catecholase activity as compared to the corresponding complexes containing acid functional groups.  相似文献   

6.
The Pd(II) and Pt(II) complexes with triazolopyrimidine C-nucleosides L1 (5,7-dimethyl-3-(2′,3′,5′-tri-O-benzoyl-β-d-ribofuranosyl-s-triazolo)[4,3-a]pyrimidine), L2 (5,7-dimethyl-3-β-d-ribofuranosyl-s-triazolo[4,3-a]pyrimidine) and L3 (5,7-dimethyl[1,5-a]-s-triazolopyrimidine), [Pd(en)(L1)](NO3)2, [Pd(bpy)(L1)](NO3)2, cis-Pd(L3)2Cl2, [Pd2(L3)2Cl4] · H2O, cis-Pd(L2)2Cl2 and [Pt3(L1)2Cl6] were synthesized and characterized by elemental analysis and NMR spectroscopy. The structure of the [Pd2(L3)2Cl4] · H2O complex was established by X-ray crystallography. The two L3 ligands are found in a head to tail orientation, with a Pd?Pd distance of 3.1254(17) Å. L1 coordinates to Pd(II) through N8 and N1 forming polymeric structures. L2 coordinates to Pd(II) through N8 in acidic solutions (0.1 M HCl) forming complexes of cis-geometry. The Pd(II) coordination to L2 does not affect the sugar conformation probably due to the high stability of the C-C glycoside bond.  相似文献   

7.
2-Phenylquinoline-4-carboylhydrazide (HL), and its novel nickel(II), zinc(II) complexes [M(HL)2(L)]·2H2O·NO3 (M = Ni (1), M = Zn (2)), have been synthesized and characterized by elemental analysis, molar conductivity, and IR spectra. The crystal structure of [Ni(HL)2(L)]·2H2O·NO3 obtained from ethanol solution was determined by X-ray diffraction analysis, crystallized in the rhombohedral system, space group , Z = 18, a = 31.913(3) Å, b = 31.913(3) Å, c = 27.709(2) Å, α = 90°, β = 90°, γ = 120°, R1 = 0.0647. The interactions of the complexes and the ligand with calf thymus DNA had been investigated using UV-Vis spectra, fluorescent spectra, CD (circular dichroism) spectra, CV (cyclic voltammetry) and viscosity measurements. These compounds were tested against MFC (mouse forestomach carcinoma) cell lines. The complex 1 showed significant cytotoxic activity against MFC cell lines. The cleavage reaction on plasmid DNA has been monitored by agarose gel electrophoresis. Results suggest that the two complexes bound to DNA via a groove binding mode and the complexes can cleave pBR322 DNA.  相似文献   

8.
The chelating behavior of 2,6-diacetylpyridine bis(2-aminobenzoylhydrazone) (H2dapa) towards manganese(II), cadmium(II) and oxovanadium(IV) ions has been studied by elemental analyses, conductance measurements, magnetic properties and spectral (IR, 1H NMR, UV-Vis and EPR) studies. The IR spectral studies suggest the pentadentate nature of the ligand with pyridine nitrogen, two azomethine nitrogens and two carbonyl oxygen atoms as the ligating sites. Six coordinate structure for [VO(H2dapa)]SO4 · H2O and seven coordinate structures for [Mn(H2dapa)(Cl)(H2O)]Cl · 2H2O and [Cd(H2dapa)Cl2] · H2O complexes have been proposed. Pentagonal bipyramidal geometry for [Mn(H2dapa)(Cl)(H2O)]Cl · 2H2O and [Cd(H2dapa)(Cl2)] · H2O complexes was confirmed by single crystal analysis. The X-band EPR spectra of the oxovanadium(IV) and manganese(II) complexes in the polycrystalline state at room (300 K) and also at liquid nitrogen temperature (77 K) were recorded and their salient features are reported.  相似文献   

9.
The title complex has been synthesized by first reacting dppp with Pd(AcO)2 in acetone and then with NaHSO4 in water. It has been characterized by IR, NMR and X-ray diffraction studies. The 31P NMR spectrum in DMSO shows a singlet at 16.62 ppm indicating that the two P atoms are equivalent and that the sulfate anion is weakly coordinating. The X-ray structure shows that the Pd atom is surrounded in an almost regular square planar environment by the two P atoms and by two O atoms of the sulfate anion and that the neutral complex is accompanied by a water molecule of crystallization. The Pd-P distances (2.217(1) and 2.233(1)) and the P-Pd-P angle (90.78(3)°) are close to those found in other complexes where the chelating diphosphine is the same. Also the Pd-O distances and the O-Pd-O bond angle are comparable to those of other relevant chelating ligands.In MeOH, the title complex, in combination with H2SO4, catalyses the CO-ethene copolymerization. The productivity reaches a maximum upon increasing the H2SO4/Pd ratio up to ca. 470 (7650 g of polyketone/g Pd h at 90 °C and 45 atm, CO/ethene 1/1). The viscosity of the polyketone passes through a maximum of 0.95 dL/g in m-cresol when the above ratio is ca. 100. It has been proposed that acid promotes the copolymerization process by destabilizing the β- and γ-chelates intermediates involved in chain growing process, thus favoring the insertion of the monomers. At relatively high acid concentration the lowering of productivity and viscosity suggests that the sulfate anion competes with the monomers for the coordination to the metal center.In H2O-CH3COOH as a solvent the productivity strongly depends on the H2O/CH3COOH ratio, as it passes through a maximum of 12 000 g polymer/g Pd h in the presence of ca. 60% of H2O. The productivity is significantly lower than that found when the acetate and chloride analogues are used (27 000 g polyketone/g Pd · h). Thus, it is likely that the sulfate anion assists significantly the copolymerization process even though the concentration of CH3COOH/CH3COO is much preponderant.  相似文献   

10.
A new ligand, L, bearing four cyanoethyl pendant groups has been synthesized by reaction of the precursor ligand L1 with acrylonitrile. The X-ray crystal structure of ligand L reveals the presence of a nanotubular structure in the solid state connected by intermolecular π,π-stacking interactions between adjacent pyridine rings. The coordination capability towards transition metal ions [Co(II), Ni(II) and Cu(II)] has been investigated starting from the hydrated nitrate and perchlorate salts of the metals. The new ligand L and the metal complexes obtained were characterized by elemental analysis, FAB MS, conductivity measurements, magnetic studies, IR and UV-vis spectroscopy. Furthermore, the crystal structure of ligand L and of the complexes [CoL][Co(NO3)4] · CH3CN (1), [NiL](NO3)2 (3), [NiL](ClO4)2 · CH3CN · 3H2O (4), [CuL][Cu(NO3)3(H2O)2](NO3) · H2O (5) and [CuL](ClO4)2 · 2CH3CN (6) were determined. The nitrate ions in the complexes are located near the pyridine rings and π,π-stacking interactions between pyridine rings, nitrate ions and nitrile groups have been found.  相似文献   

11.
The synthesis and crystal structure of two new complexes (Zn and Mn) containing tetrazolyl ligands are described. In situ [2+3] cycloaddition reactions of fipronil, (fipronil = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile) with sodium azide in the presence of ZnCl2 or MnCl2 as a Lewis acid (Demko-Sharpless tetrazole synthesis method) under hydrothermal (solvothermal) reaction conditions gave [Zn(L)2](H2O)2] · H2O, 1 and [Mn(L)2](H2O)2] · H2O, 2, (HL = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-tetrazole). The central metals in both complexes are six coordinated, which connected by two water molecules, two nitrogen atoms from different tetrazolyl groups and two nitrogen atoms from pyrazolyl rings respectively. Photoluminescence studies reveal that both title complexes exhibit strong blue fluorescent emissions at λmax = 383 nm for 1 and 411 nm for 2 respectively in the solid state at room temperature.  相似文献   

12.
In this paper, we report the synthesis and the characterization of a novel series of lanthanide (III) complexes with two potentially hexadentate ligands.The ligands contain a rigid phenanthroline moiety and two flexible hydrazonic arms with different donor atom sets (NNN′N′OO and NNN′N′N″N″, respectively for H2L1 (2,9-diformylphenanthroline)bis(benzoyl)hydrazone and H2L2 (2,9-diformylphenanthroline)bis(2-pyridyl)hydrazone).Both nitrate and acetate complexes of H2L1 with La, Eu, Gd, and Tb were prepared and fully characterized, and the X-ray crystal structure of the complex [Eu(HL1)(CH3 COO)2] · 5H2O is presented.The stability constants of the equilibria Ln3+ + H2L1 = [Ln(H2L1)]3+ and Ln3+ + (L1)2− = [Ln(L1)]+ (Ln = La(III), Eu(III), Gd(III), and Tb(III)) are determined by UV spectrophotometric titrations in DMSO at t = 25 °C. The nitrate complexes of H2L2 with La, Eu, Gd and Tb were also synthesized, and the X-ray crystal structures of [La(H2L2)(NO3)2(H2O)](NO3), [Eu(H2L2)(NO3)2](NO3) and [Tb(H2 L2)(NO3)2](NO3) are discussed.  相似文献   

13.
Five novel bpca-based Cu(II) polynuclear coordination compounds [Hbpca = bis(2-pyridylcarbonyl)amine] were prepared using the [Cu(bpca)(H2O)2](NO3)·2H2O (1) building block and characterized by single crystal X-ray diffraction. We have also isolated and characterized two new crystal forms of the starting species, with lower water contents. Three of the new products are dinuclear complexes obtained by reacting 1 with different rigid or flexible spacer ligands: [Cu2(bpca)2(H2O)2(bipy)](NO3)2·6H2O (2) (bipy = 4,4′-bipyridine) and [Cu2(bpca)2(H2O)2(bpete)](NO3)2·xH2O (3) [bpete = (E)-1,2-di(pyridin-4-yl)ethane] are linear dumbbell-like species with Cu?Cu separations of 11.075 and 13.275 Å, respectively. The third dinuclear compound, [Cu2(bpca)2(H2O)2(bpx)](NO3)2·8H2O (4) [bpx = 1,4-bis((1H-pyrazol-1-yl)methyl)benzene], with the flexible bpx ligand, assumes an unusual S-shaped conformation and shows a quite shorter Cu?Cu contact of 6.869 Å only. We have also obtained a chiral 1D neutral polymeric complex, [Cu3(bpca)2(bipy)3(NO3)4]·6H2O (5), that shows a central linear -Cu-bipy-Cu- chain, with all these Cu atoms connected to two lateral [Cu(bpca)(NO3)2] groups on two opposite sides by means of bipy spacers. An unprecedented type of Cu(II) neutral trinuclear complex, [Cu3(bpca)2(H2O)2(NO3)2] (6), was obtained which has a centrosymmetric structure with two external [Cu(bpca)(NO3)2] units chelating on a central copper atom via the two pairs of carbonyl groups of the bpca ligands. The central metal is octahedral with two axial water molecules, while the two lateral Cu atoms are in square pyramidal geometry; the Cu?Cu separation is 5.205 Å. The magnetic properties of 6 have been rationalized through a ferromagnetic coupling between the central metal ion and the peripheral ones which are coupled by a smaller antiferromagnetic interaction. DFT calculations have been also performed in order to give a better insight into magnetic interactions.  相似文献   

14.
A new ligand, 1-(pyridin-2-yl)-N-(pyridin-2-ylmethyl)-N-(thiophen-3-ylmethyl)methanamine, ThDPA, was synthesized, as a new example of an N3S donor. Cu(II) complexes of this ligand were isolated. When Cu(NO3)2 was used as the metal source, a homobinuclear complex with the formula [CuThDPA(NO3)2]2·H2O, 1, with two different types of nitro coordination was isolated. 1 crystallizes in the monoclinic P21/n space group with a = 15.193, b = 8.181, c = 32.827 Å, β = 103.3° and V = 3971.9 Å3. In the case of CuSO4 as the source of copper(II), uncommon sulfato-bridged structures were isolated. The homobinuclear complex crystallized in two different lattices, depending on the solvent evaporation rate. Compound 2, with the formula [CuThDPA(SO4)]2·3H2O, crystallizes with 3 water molecules per binuclear structure in the monoclinic space group P21/c with a = 10.143, b = 17.013, c = 11.793 Å, β = 97.18° and V = 2019.1 Å3, and 3, [CuThDPA(SO4)]2·4H2O, crystallizes with 4 water molecules per binuclear structure in the triclinic space group, with a = 9.2906, b = 10.7297, c = 12.7236 Å, α = 79.66, β = 72.18, γ = 67.1° and V = 1109.7 Å3.  相似文献   

15.
Reactions of H2L [H2L = N,N′-bis(3-methoxysalicylidene)propane-1,2-diamine] and Ln(NO3)3 · 6H2O give rise to two different mononuclear 4f complexes, namely, {[(H2L)La(NO3)3(MeOH)] · H2O}n (1) and [(H2L)Nd(NO3)3] (2). Further additions of Cu(Ac)2 · H2O to the mononuclear 4f complexes yield expected heterodinuclear Cu-4f complexes [LCu(Me2CO)Ln(NO3)3] (3, Ln = Nd; 4, Ln = Eu; 5, Ln = Dy). Complex 1 is a unique 1D polymeric chain structure, and 2 is one of the few structurally characterized discrete hexadentate salen-type mononuclear 4f complexes. Complexes 3-5 are similar to their analogues. However, they are prepared by a reversed synthetic route in contrast to their isomorphic complexes. Electrochemical behavior of heterodinuclear Cu-4f complexes 3-5 has been examined by cyclic voltammetry in acetonitrile. The redox potential of heterodinuclear Cu-4f complexes 3-5 shows significant anodic shift comparing to that of mononuclear copper complex (LCu). A tendency of anodic shift was observed in a sequence of 3 < 4 < 5. This results from the modulating effect of coordination geometry around Cu(II) ion on redox potential.  相似文献   

16.
Three new aqua magnesium phthalocyaninato complexes with 2-methoxyethylamine (MEA) in crystalline form have been obtained. The composition of the complexes depends on the crystallisation temperature. (MgPcH2O)2 · MEA (I) and (MgPcH2O)2 · 2MEA (II) were formed at about 170 °C and 80 °C, respectively, while room temperature (MgPcH2O)2 · 3MEA (III) was obtained. In all crystals the Mg atom is 4+1 coordinated, equatorially by four N-isoindole atoms of Pc ligand and axially by O atom of water molecule. The MgPc moiety is non-planar, the Mg(II) deviates by ∼0.5 Å from the N4-isoindole plane towards the oxygen atom of water molecule. The MEA molecules in the crystals interact via hydrogen bonds with coordinated water molecules of MgPcH2O. The arrangement of MgPcH2O and 2-methoxyethylamine molecules is determined by O-H?N and O-H?O hydrogen bonds and by π-π interactions. The thermogravimetric analyses show characteristic steeps responsible for the loss of MEA molecules (at lower temperature) and water (at higher temperature) and finally all the complexes transform into β-MgPc. From among the complexes only complex II exhibits an intense near-IR absorption band in the solid-state, while spectra in MEA solution are identical for all the complexes.  相似文献   

17.
The [PdII{(R,R)-chxn}(OH)2] reagent (chxn = 1,2-diaminocyclohexane) is introduced as a metal probe for the detection of the bidentate chelating sites of a glycose. Two moles of hydroxide per mole palladium support double deprotonation of potentially chelating diol functions at a glycose’s backbone. The individual chelating sites are detected using one- and two-dimensional NMR techniques. At equimolar amounts of palladium(II) and aldose, the metal-binding sites include mostly the hydroxy function at the anomeric carbon atom. Chelators are derived from both the pyranose and the furanose isomers. Most pyranose-based chelators form five-membered chelate rings by using their 1,2-diol function. Though 1,2-diolate bonding is also common to the furanoses, the formation of six-membered chelate rings by 1,3-bonding is more significant for them. Metal-excess conditions provoke mostly bis-bidentate 1,2;3,4-chelation but unusual isomers form also: thus d-xylose is dimetallated in its all-axial β-pyranose form, and erythrose’s dimetallation results in the formation of two isomers of a metal derivative of the open-chain hydrate. The spectroscopic results are supported by crystal-structure determinations on [Pd{(R,R)-chxn}(α-d-Xylp1,2H−2O1,2)]·H2O (Xyl = xylose), [Pd{(R,R)-chxn}(α-d-Ribp1,2H−2O1,2)]·2.25H2O (Rib = ribose), [Pd{(R,R)-chxn}(α-l-Thrf1,3H−2O1,3)]·2H2O (Thr = threose) and [Pd{(R,R)-chxn}(α-d-Eryf1,3H−2O1,3)]·3H2O (Ery = erythrose).  相似文献   

18.
One-pot metal promoted reactions between salicylaldehyde and 4-methyl-1,3-phenylenediamine in the presence of metal salts acting as template agents yield zinc(II) salicylaldimine complexes containing N,N′-bis(salicylidene)-4-methyl-1,3-phenylenediamine (H2L) as a result of the [2 + 1] Schiff base condensation. The complexes of formula [Zn(HL)Cl(H2O)2] · C2H5OH and [Zn(H2L)2Cl(NO3)(H2O)] · CH3OH were characterized as powder solids and in solution by spectroscopic methods (IR, 1H and 13C NMR, FAB-MS, ESI-MS, UV-Vis), thermogravimetric and elemental analysis, potentiometry, and tested for antimicrobial activity against Staphylococcusaureus in a minimum inhibitory concentration (MIC) experiment. In these two powder solid species, the salicylaldimine, formed in a self-assembly process, acts in two different coordination modes: as monodeprotonated bidentate chelator with an N,O donor set or as a neutral monodentate using exclusively oxygen as the donor atom without involving the nitrogen atoms in the coordination. However, crystals of these two complexes are isomorphous, with 1:2 metal:ligand stoichiometry, and display the latter, relatively rare coordination pattern. In solution, the presence of a 1:1 complex of monodeprotonated state is only detected. The complexes exhibit antimicrobial activity against S.aureus.  相似文献   

19.
A simple novel synthesis route to aluminum fluoride, AlF3, from aqueous phase is reported. Al2O3 is dissolved in aqueous hydrofluoric acid, HF, and re-precipitated as AlF3 · 3H2O. Thermal decomposition results in thermally stable AlF3 with high specific surface areas between 120 and 60 m2/g depending on treatment temperatures (up to 450 °C). Bulk and surface structures of the resulting amorphous and crystalline materials were characterized by X-ray powder diffraction, infrared and solid state NMR spectroscopy (27Al, MAS), nitrogen physisorption and adsorption of paramagnetic probe molecules (vanadium complexes).  相似文献   

20.
Combined pH-metric, UV-Vis, 1H NMR and EPR spectral investigations on the complex formation of M(II) ions (M=Co, Ni, Cu and Zn) with N-(2-benzimidazolyl)methyliminodiacetic acid (H2bzimida, hereafter H2L) in aqueous solution at a fixed ionic strength, I=10−1 mol dm−3, at 25 ± 1 °C indicate the formation of M(L), M(H−1L) and M2(H−1L)+ complexes. Proton-ligand and metal-ligand constants and the complex formation equilibria have been elucidated. Solid complexes, [M(L)(H2O)2] · nH2O (n=1 for M = Co and Zn, n=2 for M = Ni) and {Cu (μ-L) · 4H2O}n, have been isolated and characterized by elemental analysis, spectral, conductance and magnetic measurements and thermal studies. Structures of [Ni(L)(H2O)2] · 2H2O and {Cu(μ-L) · 4H2O}n have been determined by single crystal X-ray diffraction. The nickel(II) complex exists in a distorted octahedral environment in which the metal ion is coordinated by the two carboxylate O atoms, the amino-N atom of the iminodiacetate moiety and the pyridine type N-atom of the benzimidazole moiety. Two aqua O atoms function as fifth and sixth donor atoms. The copper(II) complex is made up of interpenetrating polymeric chains of antiferromagnetically coupled Cu(II) ions linked by carboxylato bridges in syn-anti (apical-equatorial) bonding mode and stabilized via interchain hydrogen bonds and π-π stacking interactions.  相似文献   

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