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1.
New coordination compounds of zinc with 3-(pyridine-2-yl)-5-(2-salicylideneiminophenyl)-1H-1,2,4-triazole (H2L1) and 3-(pyridine-4-yl)-5-(2-salicylideneiminophenyl)-1H-1,2,4-triazole (H2L2) are obtained. According to X-ray diffraction data, binuclear zinc complexes with L1, namely, [Zn2L21]. 0.5EtOH and [Zn2L21] · 2C4H8O2 · 2H2O obtained in different solvents, are structurally related molecular complexes. The product of the reaction with H2L2 is the {[ZnL2(Py)] · CHCl3} n coordination polymer. The 1,2,4-triazoles under study and the complexes on their basis luminesce in solutions with emission maxima ranging from 412 to 503 nm. These coordination compounds in the solid state emit in the green range of the spectrum (λmax = 496 and 485 nm).  相似文献   

2.
The two title compounds were prepared from the ligand pydc with cobalt(II) acetate in the presence of L1 and L2 (L1 = 1,3-bis(4-pyridyl)propane, L2 = 3-amino-1H-1,2,4-triazole, pydc = 2,6-pyridinedicarboxylic acid). The complexes were characterized by elemental analysis, IR spectrum and single crystal X-ray diffraction. Single crystal analysis shows that in two complexes coordination number around Co atom is six with distorted octahedral geometry, and both two complexes consist of ion pairs containing cationic [Co(H2O) n ]2+ and anionic [Co(pydc)2]2- units.  相似文献   

3.
Two new N2O2 unsymmetrical Schiff bases, H2L1 = 3-[({o-[(E)-(o-hydroxyphenyl)methylideneamino]phenyl}methyl)imino]-1-phenyl-1-buten-1-ol and H2L2 = 3-[({o-[(E)-(2-hydroxy-1-naphthyl)methylideneamino]phenyl}methyl)imino]-1-phenyl-1-buten-1-ol, and their copper(II) and nickel(II) complexes, [CuL1] (1), [CuL2] (2), [NiL1] (3), and [NiL2] (4), have been synthesized and characterized by elemental analyses and spectroscopic methods. The crystal structures of these complexes have been determined by X-ray diffraction. The coordination geometry around Cu(II) and Ni(II) centers is described as distorted square planar in all complexes with the CuN2O2 coordination more distorted than the Ni ones. The electrochemical studies of these complexes indicate a good correlation between the structural distortion and the redox potentials of the metal centers. The ligand and metal complexes were also screened for their in vitro antibacterial activity.  相似文献   

4.
A new asymmetrical substituted triazole, 3-phenoxymethyl-4-phenyl-5-(2-pyridyl)-1,2,4-triazole (L) and its complexes, cis-[Cu2 L 2Cl4]·2CH3CN (1) and trans-[CoL 2Cl2]·2H2O·2CH3CN (2), have been synthesized and characterized by IR, single-crystal X-ray diffraction, thermogravimetric analyses and Hirshfeld surfaces. In the structure, two L are mainly stabilized by an intermolecular C–H?N hydrogen bond. In 1 (or 2), each L involves a doubly-bidentate (or chelating bidentate) coordination mode through one pyridine and two nitrogens (or one) of triazole, respectively. Complex 1 has a distorted trigonal bipyramidal [CuN3Cl2] core with two cis Cl? while 2 shows a distorted octahedron [CoN4Cl2] with two trans Cl?. We also prepared molecular Hirshfeld surface and fingerprint plot for L, 1 and 2, which revealed the influence of different metals on coordinate of L.  相似文献   

5.
Three Cu(II) complexes constructed from 4-(2-pyridyl)-1H-1,2,3-triazole (L), namely, [CuL2Cl2]·H2O, [CuL2(CH3OH)(NO3)]NO3 and [CuL2(H2O)]SO4, have been synthesized and characterized. X-ray crystal structure analyses revealed that [CuL2Cl2]·H2O and [CuL2(CH3OH)(NO3)]NO3 have octahedral geometries, whilst [CuL2(H2O)]SO4 adopts a square-pyramidal coordination geometry. In all three complexes, the Cu(II) atoms are chelated by two L ligands in the basal plane, whilst the apical positions are occupied by Cl?, NO3?, CH3OH or H2O. The bandgaps between the HOMO and LUMO were estimated by cyclic voltammetry (CV) and diffuse reflectance spectroscopy (DRS) to be 3.43, 3.12, and 3.74 eV, respectively. Theoretical calculations on each structure gave similar results to the experiments. Frontier molecular orbital analyses showed that the higher electron density on the apical ligand, the lower the bandgap.  相似文献   

6.
The Cu(II) and Co(II) complexes with 3,5-diphenyl-4-amino-1,2,4-triazole (L) of the composition CuLA2 · H2O (A = Cl?, Br?), CuL2A2 (A = Cl?, Br?, NO 3 ? ), CoL2A2 · nH2O (A = Cl?, n = 1; A = NCS?, n = 0) are synthesized. In these complexes, the ligand L is coordinated to a metal in monodentate mode through the heterocyclic N(1) atom. The Cu: L = 1: 1 complexes have binuclear structures with the anions acting as bridges, whereas the M: L = 1: 2 complexes are mononuclear. Both ferro-and antiferromagnetic exchange interactions are detected for the synthesized complexes.  相似文献   

7.
Schiff base mixed-ligand copper complexes [CuL1(phen)Cl2], [CuL1(bipy)Cl2], [Cu(L1)2Cl2], [Cu(L2)2Cl2], [CuL2(bipy)Cl2], and [CuL2(phen)Cl2] (where L1?=?4-[3,4-dimethoxy-benzylidene]-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazole-3-one; L2?=?4-[3-hydroxy-4-nitro-benzylidene]-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazole-3-one; phen?=?1,10-phenanthroline; and bipy?=?2,2′-bipyridine) have been synthesized and characterized. Their DNA-binding properties have been studied by electronic absorption spectra, viscosity, and electrochemical measurements. The absorption spectral and viscosity results suggest that the copper(II) complexes bind to DNA via partial intercalation. The addition of DNA resulting in the decrease of the peak current of the copper(II) complexes indicates their interaction. Interaction between the complexes and DNA has also been investigated by submarine gel electrophoresis. The copper complexes cleave supercoiled pUC19 DNA to nicked and linear forms through hydroxyl radical and singlet oxygen in the presence of 3-mercaptopropionic acid as the reducing agent. These copper complexes promote the photocleavage of pUC19 DNA under irradiation at 360?nm. Mechanistic study reveals that singlet oxygen is likely to be the reactive species responsible for the cleavage of plasmid DNA by the synthesized complexes. The in vitro antimicrobial study indicates that the metal chelates have higher activity against the bacterial and fungal strains than the free ligands.  相似文献   

8.
Two novel complexes, [Zn(dmatrz)2]Cl2 (1) and [Zn(dmatrz)2(SCN)2] (2), have been prepared and characterized by X-ray crystallography, absorption and luminescence spectrometries (dmatrz=3,5-dimethy-4-amino-1,2,4-triazole). The coordination environment of the zinc(II) ions in (1) and (2) has a distorted tetrahedral geometry completed via two independent nitrogen atoms of two triazole ligands and two anions, respectively. Both (1) and (2) show strong blue luminescence properties. Furthermore, (1) displays stronger blue photoluminescence than (2) as the result of different anions (Cl- and SCN-) coordinated to the zinc(II) ions.  相似文献   

9.
Novel oligonuclear complexes of Co(II), Ni(II), and Cu(II) with 4-(3,4-dichlorophenyl)-1,2,4-triazole (L) of the composition [M3L10(H2O)2](NO3)6 (M = Co(II), Ni(II)), [Ni3L6(H2O)6]Hal6 (Hal = Cl?, Br?), and [Cu5L16(H2O)2](NO3)10 · 2H2O were synthesized and studied by magnetic susceptibility, electronic and IR spectroscopy, and powder X-ray diffraction methods. All the above complexes are X-ray amorphous. Antifer-romagnetic exchange interactions between the M2+ ions were discovered in the [Co3L10(H2O)2](NO3)6 and [Ni3L10(H2O)2](NO3)6 complexes, whereas ferromagnetic exchange interactions were observed in the complexes [Ni3L6(H2O)6]Cl6, [Ni3L6(H2O)6]Br6, and [Cu5L16(H2O)2](NO3)10 · 2H2O.  相似文献   

10.
A series of new 3d-metal complexes based on 2-amino-3-(1-methylbenzimidazol-2-yl)-4(5H)-ketothiophen (HL1) and 2-amino-3-(2-benzothiazolyl)-4(5H)-ketothiophen (HL2) were synthesized. Compounds of the general formulas [ML2] and [M(HL1)2Cl2] (where M = Co2+, Ni2+, Zn2+, Cu2+) were prepared by the reaction of the above mentioned ligands with the corresponding acetate (for [ML2]) or chloride (for [M(HL1)2Cl2]) salts in a methanol or a methanol–chloroform medium. The choice of the anion in the initial metal salt, as well as the selection of the ligand, is crucial for obtaining coordination compounds with a neutral or deprotonated form of the 2-amino-4(5H)-ketothiophens. Thus, in contrast to HL1, complexes with the neutral form of HL2 cannot be obtained under the same conditions. All the complexes were studied by spectroscopic methods and X-ray crystallography (for [CuL12] · H2O). The coordination polyhedron of the copper atom is formed by four nitrogen atoms from two ligand anions and the geometry of the coordination sphere is intermediate between tetrahedral and square-planar.  相似文献   

11.
2-Formylpyridine 4-(2,6-dimethylphenyl)-(HL1), 4-(2,5-dimethylphenyl)-(HL2), 4-(3,4-dimethylphenyl)-(HL3), and 4-(2,4-dimethylphenyl)thiosemicarbazones (HL4) react with copper chloride and nitrate to form coordination compounds CuL1–4nH2O [X = Cl?, NO 3 ? ; n = 1, 2]. All compounds have a polynuclear structure. Azomethines HL1–4 act as the bridging monodeprotonated tridentate N,N,S-ligands. The thermolysis of the complexes includes the dehydration (70–90°C) and total thermal decomposition (350–520°C). The complexes synthesized exhibit a selective antimicrobial activity against a series of standard strains of Staphylococcus aureus and Escherichia coli in the concentration range of 0.009–37.5 μg ml?1.  相似文献   

12.
A new ligand, 3-methyl-4-(p-bromophenyl)-5-(2-pyridyl)-1,2,4-triazole (L) and its complexes, trans-[CuL2(ClO4)2] (1) and cis-[CoL2(H2O)2](ClO4)2·H2O·CH3OH (2), have been synthesized and characterized by UV, IR, electrospray ionization mass spectrum, elemental analyses, and single-crystal X-ray diffraction methods. In the structure, two L ligands are stabilized by intermolecular π···π interactions between the triazole rings. In the complexes, each L ligand adopts a chelating bidentate mode through N atom of pyridyl group and one N atom of the triazole. Both complexes have a similar distorted octahedral [MN4O2] core (M = Cu2+ and Co2+) with two ClO4 ions in the trans position in 1 but two H2O molecules in the cis arrangement in 2.  相似文献   

13.
Liu  Jie  Lu  Tong-Bu  Deng  Hong  Ji  Liang-Nian  Qu  Liang-Hu  Zhou  Hui 《Transition Metal Chemistry》2003,28(1):116-121
Two macrocyclic copper(II) complexes, [CuL1](ClO4)2 (L1 = 2,6,9,13-tetraparacyclophane, a Schiff base) and [CuL2]Cl2 [L2 = 3,10-bis(2-benzyl)-1,3,5,8,10,13-hexaazacyclotetradecane] have been prepared and characterized by elemental analysis, u.v.–vis., i.r. and mass spectra. Absorption, fluorescence, circular dichroic spectra and viscosity experiments have been carried out on the interaction of the two complexes with calf thymus CT DNA. The results suggest that both complexes can bind to CT DNA by intercalation via the aromatic moiety ring in the macrocycle into the base pairs of DNA. [CuL1](ClO4)2 binds to CT DNA more strongly than [CuL2]Cl2. The position of the aromatic ring in the macrocycle plays an important role in deciding the extent of binding of the complexes to DNA. Significantly, the complexes have been found to be single-strand DNA cleavers in the presence of H2O2 or/and 2-mercaptoethanol.  相似文献   

14.
Two copper(I) complexes [Cu(Cin2bda)2]ClO4 (I) and [Cu(Ncin2bda)2]ClO4 (II) have been prepared by the reaction of the ligands N2,N2′-bis(3-phenylallylidene)biphenyl-2,2′-diamine (L1) and N2,N2′-bis[3-(2-nitrophenyl)allylidene]biphenyl-2,2′-diamine (L2) and copper(I) salt. These compounds were characterized by CHN analyses, 1H NMR, IR, and UV-Vis spectroscopy. The C=N stretching frequency in the copper(I) complexes shows a shift to a lower frequency relative to the free ligand due to the coordination of the nitrogen atoms. The crystal and molecular structure of II was determined by X-ray single-crystal crystallography. The coordination polyhedron about the copper(I) center in the complex is best described as a distorted tetrahedron. A quasireversible redox behavior was observed for complexes I and II. The article is published in the original.  相似文献   

15.
Abstract

The reaction between CuX2 (X = Cl, Br, NO3, ClO4) and 2-S-methyl-5,5-dimethylimidazolin-4-one (L) yields complexes having stoichiometry CuL2Cl2 · 1/2H2O (1), CuL2Br2 (2), CuL4X2 · 2H2O [X = NO3 (3), ClO4 (4)]. The X-ray crystal structure solved for 1 showed that it contains discrete [CuL4 · H2O]2+ and [CuCl4]2- ions, separated by normal van der Waals contacts. The [CuL4H2O]2+ cation has crystallographic C 4 symmetry, with the copper atom and the oxygen of the water molecule lying on a four-fold axis of the space group P4/n and the metal atom in a square-pyramidal coordination geometry, obtained by a square basal plane defined by four N atoms and the apex occupied by the water molecule. The [CuCl4]2- anion shows a very flattened tetrahedral geometry. FT-IR and FT-Raman spectra of 1–4 show that 2,3 and 4 also are N(3)-coordinated to copper; nitrate and perchlorate do not coordinate. The v(CuO) vibrations are present at about 380 cm?1 for 3 and 4, while for 2 v(CuBr) are at 224 and 215 cm?1. Esr data for 1–4 recorded on solid samples highlight a dx 2 - y2 ground state for the cation of 1, 3, and 4 which is typical for tetragonally elongated monomeric copper(II) complexes. Compound 2 exhibits two couples of g values characteristic of two independent copper centres both with compressed tetrahedral geometry. The deconvoluted reflectance spectra of 1–4 substantially confirm the presence of CuN4 and CuBr4 chromophores in 2 and a trans-CuN4O2 chromophore in 3 and 4. For the latter complexes an orbital sequence dx2 - y2 > dxy > dz2 > dxy, dyz is also suggested on the basis of the similarity between L and imidazole type ligands.  相似文献   

16.
The complexes FeLCl2 (I), [FeL1Cl2] (II), [CoL1Cl2] (III), and [CuL1Cl2] (IV) (where L and L1 are chiral and achiral pyrazolylquinolines, respectively) were obtained. Complexes II–IV were structurally characterized by single-crystal X-ray diffraction analysis. Crystals of complexes II and III are triclinic (space group P $ \bar 1 The complexes FeLCl2 (I), [FeL1Cl2] (II), [CoL1Cl2] (III), and [CuL1Cl2] (IV) (where L and L1 are chiral and achiral pyrazolylquinolines, respectively) were obtained. Complexes II–IV were structurally characterized by single-crystal X-ray diffraction analysis. Crystals of complexes II and III are triclinic (space group P ) and crystals of complex IV are monoclinic (space group P21/n). Structures II–IV are built from discrete mononuclear acentric molecules. In these complexes, the M2+ ion (M = Fe, Co, and Cu) coordinates two N atoms of the bidentate chelating ligand L1 and two Cl atoms. The coordination cores MCl2N2 are distorted tetrahedra. For complexes I and II, μeff = 5.05 and 5.07 μB, respectively, correspond to the high-spin configuration d 6. For complex III, μeff = 4.51 μB (high-spin configuration d 7) and for complex IV, μeff = 1.80 μB (configuration d 9). Original Russian Text ? Z.A. Savel’eva, L.A. Glinskaya, R.F. Klevtsova, S.A. Popov, A.V. Tkachev, N.V. Semikolenova, V.A. Zakharov, S.V. Larionov, 2008, published in Koordinatsionnaya Khimiya, 2008, Vol. 34, No. 4, pp. 285–292.  相似文献   

17.
Twenty new complexes were synthesized by reacting Co(II), Cu(II), Zn, Cr(III), Fe(III), Cd and Ag salts with 3,3-dimethyl-1-(3-methylpyrazole-5-onilidene-4)-1,2,3,4-tetrahydroisoquinoline (L1), spiro{cyclohexane-1,3"-[1-(1-phenyl-3-methylpyrazole-5-onilidene-4)-1,2,3,4-tetrahydroisoquinoline]} (L2), and 3,3-dimethyl-1-(1-phenyl-3-methylpyrazole-5-onilidene-4)-1,2,3,4-tetrahydroisoquinoline (L3). These compounds were studied by IR and electronic absorption spectroscopy. The type of coordination of their ligands was discussed on the basis of the results obtained and X-ray diffraction data for L3 and [CuL2 2 Cl2] · 2L2 obtained previously.  相似文献   

18.
Novel copper(II) complexes, molecular [Cu66-Cl)(μ3-OH)2(μ-L)6Cl9(H2O)3] · 3H2O (1) and polymeric [Cu(μ-L)(μ-OH)(H2O)2]Cl (2) (L = 4-(4-hydroxyphenyl)-1,2,4-triazole), have been prepared and characterized by X-ray structural analysis. Compound 1 appears to be an unusual example of a chloride ion with six equal Cu–Cl distances of 2.8397(3) Å. It has also been characterized by X-ray powder diffraction and magnetic measurements. Both complexes have distorted octahedral configurations of copper ions; the coordination cores are CuN2Cl2O2 or CuN2Cl3O (1) and CuN2O4 (2).  相似文献   

19.
Three supramolecular complexes [Zn(HL1 )2(H2O)2(ZnCl4)2] (1), [Cu(L2 )2Cl2] (2), and [Zn(L3 )Cl2] (3) have been synthesized and characterized by single crystal X-ray diffraction analysis (L1 = 3,5-di(2-pyridyl)-4-amino-1,2,4-triazole, L2 = 3,5-di(2-pyridyl)-1,2,4-triazole, and L3 = 2-pyridinecarboxylic acid (pyridin-2-ylmethylene)-hydrazide). In 1, anion–π interactions between Cl? and the π-systems of L1 are observed and anion–π, hydrogen bonding and π–π stacking interactions link the two complex units of [Zn(HL1 )2(H2O)2]4+ and [ZnCl4]2? to form a 3-D supramolecular network. In 2, π–π stacking interactions between aromatic rings of 1,2,4-triazole and pyridine rings are observed; in 3, hydrogen bonding of Cl ··· H–N and π–π stacking interactions between parallel pyridine rings of L 3 are observed. The mechanisms of rearrangement reactions of L to L1 L3 are discussed. The fluorescent properties for solid 1 and 3 are also investigated.  相似文献   

20.
New complexes of Co(II), Ni(II), and Cu(II) nitrates, chlorides, and perchlorates with 4-(4-hydroxyphenyl)-1,2,4-triazole (L) were obtained and examined by single-crystal X-ray diffraction, X-ray powder diffraction, and electronic absorption and IR spectroscopy. The cations of all the complexes have linear trinuclear structures. Ligand L is coordinated to the metal ions in a bidentate bridging fashion through the N(1) and N(2) atoms of the heterocycle. The coordination polyhedron of the metal atoms is a distorted octahedron. The molecular and crystal structures of the complexes [Co3L6(H2O)6](ClO4)6 · 3C2H5OH · 3.75H2O and [M3L6(H2O)6](ClO4)6 · 6H2O (M = Cu2+ and Ni2+) were determined.  相似文献   

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