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1.
Copper(II) complexes with 3-N,N-dimethylaminocaran-4-one-oxime (HL) were synthesized and characterized by X-ray diffraction analysis, photoelectronic, IR, and EPR spectroscopy, magnetic susceptibility, and thermal analysis methods, and their optical activities were studied. The [Cu2(HL)2Cl4] complex is a dimer with weak exchange interactions between unpaired electrons of the Cu(II) ions. The [Cu3L3(OH)Cl]Cl · 8H2O structure is composed of triangular trinuclear complex cations, outer-sphere Clanions, and water molecules. The exchange parameter Jfor the trinuclear exchange cluster is –190 cm–1. The title complexes are optically active in the visible range of the spectrum.  相似文献   

2.
A series of new 3d metal complexes based on dimethyl pyridin-2-ylcarbamoylphosphoramidate (HL) was synthesized. The compounds with general formula M(HL)2Cl2·nH2O and M(L)2·nH2O (M=Co2+, Cu2+, Ni2+) were characterized by means of single-crystal X-ray analysis and IR spectroscopy. The organic ligands in all complexes are coordinated via oxygen atom of the carbonyl group and nitrogen atom of the heterocycle. The coordination environment of the central atoms is a distorted octahedron. The axial positions in the Co(II) and Ni(II) complexes with deprotonated ligands are occupied by water molecules. The Co(II) and Cu(II) complexes with phosphoryl ligands in a neutral form have different ligands in the axial positions: in the Co(II) complex, the positions are occupied by two water molecules, whereas in the Cu(II) complex, the positions are occupied by two chlorine anions. The structure of HL was experimentally and theoretically obtained by utilizing single-crystal X-ray analysis and DFT calculations. The computationally optimized geometric parameters for HL show a good agreement with the experimental results.  相似文献   

3.
New Co(II), Ni(II), and Cu(II) complexes were synthesized with the Schiff base ligand obtained by the condensation of sulfathiazole with salicylaldehyde. Their characterization was performed by elemental analysis, molar conductance, spectroscopic techniques (IR, diffuse reflectance and UV–Vis–NIR), magnetic moments, thermal analysis, and calorimetry (thermogravimetry/derivative thermogravimetry/differential scanning calorimetry), while their morphological and crystal systems were explained on the basis of powder X-ray diffraction results. The IR data indicated that the Schiff base ligand is tridentate coordinated to the metallic ion with two N atoms from azomethine group and thiazole ring and one O atom from phenolic group. The composition of the complexes was found to be of the [ML2]∙nH2O (M = Co, n = 1.5 (1); M = Ni, n = 1 (2); M = Cu, n = 4.5 (3)) type, having an octahedral geometry for the Co(II) and Ni(II) complexes and a tetragonally distorted octahedral geometry for the Cu(II) complex. The presence of lattice water molecules was confirmed by thermal analysis. XRD analysis evidenced the polycrystalline nature of the powders, with a monoclinic structure. The unit cell volume of the complexes was found to increase in the order of (2) < (1) < (3). SEM evidenced hard agglomerates with micrometric-range sizes for all the investigated samples (ligand and complexes). EDS analysis showed that the N:S and N:M atomic ratios were close to the theoretical ones (1.5 and 6.0, respectively). The geometric and electronic structures of the Schiff base ligand 4-((2-hydroxybenzylidene) amino)-N-(thiazol-2-yl) benzenesulfonamide (HL) was computationally investigated by the density functional theory (DFT) method. The predictive molecular properties of the chemical reactivity of the HL and Cu(II) complex were determined by a DFT calculation. The Schiff base and its metal complexes were tested against some bacterial strains (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis). The results indicated that the antibacterial activity of all metal complexes is better than that of the Schiff base.  相似文献   

4.
2-[2-(Hydroxybenzylidene)-amino]-2-hydoxymethylpropane-1,3-diol (HL) reacts with cobalt, nickel, copper and zinc chlorides, bromides and acetates in water–ethanol solutions and gives MLX · nH2O and ML2 · nH2O complexes (M = Co, Ni, Cu, Zn; X = Cl, Br; n = 0–5). Single crystals of CuLBr were grown, and its crystal structure was determined by X-ray diffraction analysis. The crystals are tetragonal, a = 17.024(2), c = 8.720(2) Å, space group P 21 c, Z = 8, R 1 = 0.0349. In the structure of this complex, the copper atom coordinates the deprotonated HL molecule. The coordination polyhedron of the central atom is an elongated tetragonal pyramid. Its base is built of the imine nitrogen atom, phenolic and alcoholic oxygen atoms, and bromine atom. The apex of the pyramid is occupied by the bromine atom of the adjacent complex connected with the initial complex by the plane of sliding reflection. Thus, the crystal contains infinite chains of complexes running along the c axis, the complexes being united by both bridging bromine atoms and O–H···O hydrogen bonds. The conclusions on the compositions and structures of the remaining compounds were made on the basis of elemental and combined thermal analyses, IR spectroscopy, and magnetic chemistry data. The copper halide complexes were found to have dimeric, and the other metal complexes monomeric, structures. In the synthesized complexes, the azomethine HL can function as a bidentate or tridentate ligand. The thermolysis of the coordination compounds proceeds through the stages of elimination of crystal water molecules (75–90°C) or inner-sphere water molecules (145–155°C) and complete thermal destruction (485–550°C).  相似文献   

5.
Complexes of Co2+, Ni2+, and Cu2+ with N-(phosphonomethyl)aminosuccinic acid (H4PMAS) of general formula Na2MPMAS·nH2O [M=Co(II), Ni(II), Cu(II), n—number of water molecules] were synthesized. Based on interpretation of diffusion reflectance spectroscopy, structure of all complexes is based on distorted octahedral. Analysis of IR spectra of Co(II), Ni(II), and Cu(II) N-(phosphonomethyl)aminosuccinates demonstrated that metal ions are coordinated to the ligand through nitrogen atom of the imino group, oxygen atoms of the α- and β-carboxyl groups as well as oxygen atom of the phosphonic group of the H4PMAS. We demonstrated that thermal stability of complexes increases in sequence Cu(II) < Ni(II) < Co(II), obviously as a result of change over from the dimeric to polymeric character of the initial complex. Complete decomposition of ligand occurs at these temperatures and is accompanied by release of H2O, CO2, and NO2. The final products of thermal decomposition of the complexes are mixtures of oxides and phosphates of respective metals.  相似文献   

6.

A tridentate ONN donor Schiff-base hydrazone ligand, H2L, was synthesized by the condensation of 2-amino-4-hydrazino-6-methyl pyrimidine with o-hydroxyacetophenone. The structure of the ligand was elucidated by IR and 1H NMR spectra which indicated the presence of three different coordinating groups, the oxygen atom of the phenolic OH group, the nitrogen atom of the azomethine, C=N, group and one of the nitrogen atoms of the heterocyclic ring. The ligand behaves either as a tridentate (N2O sites) neutral, mono- or di-basic ligand or as a bidentate (NO sites) monobasic ligand depending on the pH of the reaction medium and the metal ion. The mass spectrum of the ligand showed the presence of the molecular ion peak. Different types of metal complexes, mononuclear such as [(HL)M(OAc)]·xH2O (M = Cu or Zn), [(HL)M(OAc)H2O]·xH2O (M = Ni or UO2), [(HL)Co(OH2)Cl]·2H2O, [(H2L)FeCl3]·3½H2O, [(L)FeCl(H2O)2]· 2¼H2O, [(HL)L'FeCl(H2O)]·H2O (L' = 8-hydroxyquinoline, 8-HQ), [(HL)L'FeCl]Cl·xH2O (L' = 1,10-phenanthroline, phen, or 2,2'-bipyridyl, bpy) and [(HL)L'Cu]·ClO4 (L' = phen). Also, binuclear complexes with oxalic acid of the type [(HL)ClFe(ox)FeCl(HL)], [(HL)Cu(ox)Cu(HL)] were obtained. The IR spectra of the binuclear complexes indicated that the oxalate anion acts as a bridging tetradentate ligand. Elemental analyses, IR, electronic and ESR spectra as well as conductivity and magnetic susceptibility measurements were used to elucidate the structures of the newly prepared metal complexes. Square-planar geometry is suggested for the Cu(II) complex, octahedral geometry for the Fe(III), Ni(II) complexes, tetrahedral geometry for the Co(II) and Zn(II) complexes and pentagonal-bipyramidal geometry for the UO2(VI) complex.  相似文献   

7.
Nickel(II) complexes of general empirical formula, NiLX·nH2O (L = deprotonated form of the Schiff base formed by condensation of N-methyl-S-methyldithiocarbazate with 2-hydroxybenzaldehyde or 5-bromo-2-hydroxybenzaldehyde; X = Cl, Br, NCS, AcO or CN; n = 0, 1) have been prepared and characterized by a variety of physico-chemical techniques. Magnetic and spectroscopic data support a square-planar structure for these complexes. The crystal structure of the [Ni(ONMeS)CN]·H2O complex (ONMeS = anionic form of the 2-hydroxybenzaldehyde Schiff base of N-methyl-S-methyldithiocarbazate) has been determined by X-ray diffraction. The complex has a distorted square-planar structure in which the Schiff base is coordinated to the nickel(II) ion as a uninegatively charged anion coordinating via the phenolic oxygen atom, the azomethine nitrogen atom and the thione sulfur atom. The fourth coordination position is occupied by a cayano ligand. The antifungal properties of the Schiff bases and their nickel(II) complexes were studied against three plant pathogenic fungi. The ligands display moderate fungitoxicities against these organisms but their nickel(II) complexes are less active than the free ligands.  相似文献   

8.
The reactions of Co(II), Ni(II), and Cu(II) chlorides and bromides and their metallic powders with tetrazol-1-yl-tris(hydroxymethyl)methane (L) afforded new complexes ML2Hal2 · mH2O(M = Co(II) or Ni(II), Hal = Cl; M = Cu(II), Hal = Cl or Br, m = 0; and M = Co(II) or Ni(II), Hal = Br, m = 2), MLnCl2 (M = Co(II) or Ni(II), n = 2 or 4; M = Cu(II), n = 2), and MLnBr2 · mH2O (M = Ni(II), n = 2, m = 2; M = Cu(II), n = 2, m = 0). The compositions and structures of the synthesized complexes were determined by elemental analysis, IR spectroscopy (50–4000 cm−1), and X-ray diffraction analysis. The introduction of a bulky substituent into position 1 of the tetrazole cycle was shown to exert almost no effect on the coordination mode but affected the composition and structure of the complexes.  相似文献   

9.
This paper presents examples of mixed-ligand Co(II), Cu(II), Ni(II) and Mn(II) complexes, with a distorted octahedral coordination geometry, with 2,2′-dipyridyl or 1,10-phenanthroline and phosphortriamide ligands. The complexes of the general type ML2·Lig (where M = Co(II), Cu(II), Ni(II), Mn(II); L = {Cl3C(O)NP(O)R2} (R = NHBz, NHCH2CHCH2, NEt2); Lig = 2,2′-dipyridyl or 1,10-phenanthroline) were synthesised and characterised by means of X-ray diffraction, IR and UV–Vis spectroscopy. The phosphortriamide ligands are coordinated via oxygen atoms of phosphoryl and carbonyl groups involved in six-membered metal cycles. The additional ligands 2,2′-dipyridyl or 1,10-phenanthroline are coordinated to the central atom, forming five-membered cycles.  相似文献   

10.
Summary A series of cobalt(II), nickel(II) and copper(II) complexes of 2-picolinamineN-oxide, HA, has been prepared. Solids of formula [M(HA)3](BF4)2 (M=cobalt(II) or nickel(II); [Cu(HA)2]X2 (X=BF 4 , NO 3 ); [Co(HA)2X2] (X=Cl or Br); [Ni(HA)2Cl2] and [Cu(HA)X2] (X=Cl or Br] have been isolated and characterized by partial elemental analyses, molar conductivities, magnetic susceptibilities, DSC-TGA, and spectral methods. All complexes were found to be monomeric, and their spectral parameters are compared with those of the metal ion complexes ofN-alkyl-2-picolinamineN-oxides, 2-dialkylaminopyridineN-oxides and 2-picolinamine. The cobalt(II) and nickel(II) halide complexes spectrally show a mixture of octahedral and tetrahedral centres.  相似文献   

11.
Copper(II) complexes of general formula, Cu(NNS)X 2 · nH2O (NNS = the 2-formylpyridine Schiff base of N-methyl-S-methyldithiocarbazate; X = Cl, Br, I, NCS; n = 0, 2) have been synthesized and characterized by elemental analysis and by magnetic and spectroscopic techniques. Based on magnetic and spectroscopic data, a monomeric five-coordinate square-pyramidal structure is assigned to these complexes. The crystal and molecular structure of [Cu(NNS)I2] has been determined by X-ray diffraction. The complex has a monomeric square-pyramidal structure with the ligand coordinated to the copper(II) ion via the pyridine nitrogen atom, the azomethine nitrogen atom and the thione sulfur atom. The fourth and fifth coordination sites are occupied by the iodide ligands. Antimicrobial tests indicate that Schiff base is inactive against the bacteria, Bacillus subtilis (mutant defective DNA repair), Pseudomonas aeruginosa, methicillin resistant Staphylococcus aureus and Bacillus subtilis (wild type) and weakly active against the fungi, Candida albicans, Candida lypolytica, Saccharomyces cereviseae and Aspergillus ochraceous but its copper(II) complexes, Cu(NNS)X 2 are strongly active against these organisms. A cytotoxicity study of the compounds against leukemic and cervical cancer cells showed that the Schiff base is inactive, but the complexes, [Cu(NNS)I2] and [Cu(NNS)(NCS)2] · 2H2O exhibit significant activity against cervical cancer cells with CD50 values of 4.8 and 4.2 g, respectively.  相似文献   

12.
Summary Nickel(II) and copper(II) complexes of 2,5-dimethyl-1,3,4-thiadiazole Ni(DTZ)X2 (X = Cl or Br) and M(DTZ)2X2 (M = Ni, X = 1 or N03; M = Cu, X = Cl, Br or NO3) have been prepared. The i.r. spectra show that in all the complexes the ligand is N,N- or N-bonded to the metal while the sulfur atom does not participate in coordination, and that the halide ions are coordinated forming terminal M-X bonds. The NO 3 - group is coordinated in both the nitrato complexes. Magnetic moments of 3.07–3.29 B.M. for the nickel(II) and 1.86–1.92 B.M. for the copper(II) complexes were observed. The Ni(DTZ)X2 complexes have a pseudo-tetrahedral [N2X2] coordination with N,N-bridging ligand molecules. The Ni(DTZ)2X2 and Cu(DTZ)2X2 complexes, with predominantly monodentate ligand, involve six-coordinate metal atoms with strong equatorial [N2X2] bonds and weaker axial bonds.Author to whom all correspondence should be directed.  相似文献   

13.
Summary Some copper(II) complexes of the type Cu(HL)X·nH2O (where H2L = benzoin thiosemicarbazone; X=NO3; Cl, Br, SCN, ClO4 or 1/2SO4; n=O–2) have been prepared and characterized. All complexes have tetragonally distorted octahedral stereochemistry except the sulphatocomplex which is square pyramidal. The i.r. spectra reveal that HL acts as a monobasic tridentate ligand coordinating through the azine group nitrogen atom, thiocarbonyl sulphur atom and hydroxylic oxygen atom while NO3, Cl, Br and ClO4 act as terminal monodentate ligands and SCN and SO4 act as bidentate bridging ligands. The polycrystalline e.s.r. spectra suggest tetragonal symmetry for the copper(II) ion, involving a dx 2–y2 ground state.  相似文献   

14.

A tridentate ONN donor ligand, 5-methyl-3-(2-hydroxyphenyl)pyrazole; H2L, was synthesized by reaction of 2-(3-ketobutanoyl)phenol with hydrazine hydrate. The ligand was characterized by IR, 1H NMR and mass spectra. 1H NMR spectra indicated the presence of the phenolic OH group and the imine NH group of the heterocyclic moiety. Different types of mononuclear metal complexes of the following formulae [(HL)2M][sdot]xH2O (M=VO, Co, Ni, Cu, Zn and Cd), [(HL)2M(H2O)2] (M=Mn and UO2) and [(HL)LFe(H2O)2] were obtained. The Fe(III) complex, [(HL)LFe(H2O)2] undergoes solvatochromism. Elemental analyses, IR, electronic and ESR spectra as well as thermal, conductivity and magnetic susceptibility measurements were used to elucidate the structures of the newly prepared metal complexes. A square-pyramidal geometry is suggested for the VO(IV) complex, square-planar for the Cu(II), Co(II) and Ni(II) complexes, octahedral for the Fe(III) and Mn(II) complexes and tetrahedral for the Zn(II) and Cd(II) complexes, while the UO2(VI) complex is eight-coordinate. Transmetallation of the UO2(VI) ion in its mononuclear complex by Fe(III), Ni(II) or Cu(II) ions occurred and mononuclear Fe(III), Ni(II) and Cu(II) complexes were obtained. IR spectra of the products did not have the characteristic UO2 absorption band and the electronic spectra showed absorption bands similar to those obtained for the corresponding mononuclear complexes. Also, transmetallation of the Ni(II) ion in its mononuclear complex by Fe(III) has occurred. The antifungal activity of the ligand and the mononuclear complexes were investigated.  相似文献   

15.
Copper(II) complexes with (1R*,4S*)-1-N-morpholino-n-menth-8-en-4-one (HL), namely, [Cu2(HL)2Cl4] (I) and [Cu2(HL)LCl3] · CH3CN (II), were synthesized and characterized by X-ray diffraction analysis, magnetic susceptibility, and EPR methods. The complexes have binuclear structures. In compound I, the coordination polyhedron of CuCl3N2 is a square pyramid in planar Cu2Cl2 metal cycle; the exchange couplings of unpaired electrons of Cu(II) ions are weak. Complex II incorporates polyhedra of CuCl2N2 (flattened tetrahedron) and of CuCl2N2O (trigonal bipyramid). The Cu2ClNO metal cycle is nonplanar with antiferromagnetic exchange coupling and exchange parameter –2J = 182 cm–1. The EPR spectrum of compound I are analyzed.  相似文献   

16.
Crystal structure of 2,3-dihydroxypyridine (H2L) is determined. Mn(HL)Cl · H2O, Co(HL)Cl · 2H2O, Cu(HL)Cl, Ni(HL)OH · H2O, and Zn(HL)OH · H2O complexes are synthesized by reacting Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) chlorides with H2L in ethanol solutions and identified. In these complexes, 2,3-dihydroxypyridine is involved in coordination as a monoanion. Spectral parameters of neutral and anionic forms of a ligand are determined and the acidity and complex formation constants are calculated. The compositions of complexes are established.  相似文献   

17.
Potentially tetradentate ligands N,N"-di(2-hydroxybenzyl)ethylenediamine (L1) and N,N"-di(2-hydroxybenzyl)o-phenylenediamine (L2) and complexes of Cu(II), Co(II), and Ni(II) with L1and L2were synthesized. The EPR and electronic spectroscopy methods were used to reveal the octahedral structure of the Cu(II) complex with L1in the solid state. In water–alcohol solutions, the Cu(II) and Ni(II) complexes with both ligands have distorted octahedral structures. The Co(II) complexes form dioxygen adduct with L1. In the presence of oxygen, the ligands in the obtained complex compounds can undergo oxidative dehydrogenation with selective formation of the respective disalicylaldimines. In the case of L2, the oxidative dehydrogenation is observed for the complexes of all studied metals in comparatively mild conditions (T= 30°C, methanol and other solvents), while in the case of L1, it occurs only with the Co(II) complexes in the presence of pyridine.  相似文献   

18.
Summary New complexes of general formulae [Ni(HL)2], [ML]·H2O and [Cu(HL)X] (H2L = pyrrole-2-aldehyde Schiff bases ofS-methyl- andS-benzyldithiocarbazates; X = Cl or Br; M = NiII, CuII, ZnII or CdII) were prepared and characterized by a variety of physicochemical techniques. The Schiff bases coordinate as NS bidentate chelating agents in [Ni(HL)2] and [Cu(HL)X], and as tridentate NNS chelates in [ML] (M = NiII, CuII, ZnII or CdII). Both the [Ni(HL)2] and [NiL] complexes are diamagnetic and square-planar. Based on magnetic and spectroscopic evidence, thiolate sulphur-bridged dimeric square-planar structures are assigned to the [Cu(HL)X] and [ML] (M = NiII or CuII) complexes. The complexes ML (M = ZnII or CdII) are polymeric and octahedral.  相似文献   

19.
Thermal decomposition of Ni(II), Pd(II), and Pt(II) complexes of N-pyrimidin-2ylthiourea (AllPmTu) have been studied by TG, DTG, and DTA and by electron impact (EI) mass spectra. The complexes have the molecular formulae as [Ni(AllPmTu)Cl2(H2O)], [Ni(AllPmTu)2Cl2(H2O)2], and [M(AllPmTu)Cl2], where M = PdII or PtII, and [Pt(AllPmTu)2]. The TG curves show that Ni(II) complexes decompose in three stages to yield NiO as a residue, while Pd(II) and Pt(II) decompose in two stages to yield MS residues. The initial mass losses correspond to elimination of allylamine for Pd(II) and Pt(II) complexes but, allyisothiocyanate for both Ni(II) complexes revealing that sulfur atom of thiourea part is involved in coordination to Pd(II) and Pt(II) but does not to Ni(II). Kinetic parameters (E #, n, ΔH #, ΔS #, ΔG #) of the decomposition stages are determined and correlated with bonding and structural properties of the complexes. The EI mass spectra of the complexes show fragments corresponding to the evolved and intermediate species.  相似文献   

20.
Summary The syn-2-picolyl phenyl ketoxime (HL1) and the syn-2-quinaldyl phenyl ketoxime (HL2) give [M(HL)LX], [M(HL)2X2] and [ML] solid complexes (M=Co, Ni and Cu; X=Cl, Br and NO 3 which have been characterized by elemental analysis, room temperature magnetic moments and electronic and i.r. spectral measurements.  相似文献   

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