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1.
Cerium(IV), Thorium(IV) and Uranyl(II) complexes with the ammonium salt of sulfasalazine drug (H2SSZ, HL-) have been studied. The structures of the complexes were elucidated using elemental analysis, IR and mass spectroscopy and thermal analysis. The complexes were isolated in 1:1 and 1:2 (M:L) ratios. The solid monocomplexes (1:1) (M:H(2)SSZ) were isolated in the general formulae [UO2(L)(H2O)2].2H2O and [M(L)(X)z(H2O)n].yH2O (M=Ce(IV) and Th(IV) (X=NO3, z=2, n=2, y=0-3)). The biscomplexes (1:2) (M:H2SSZ) solid chelates found to have the general formulae [UO2(HL)2].2H2O and [M(L)2(H2O)2] (M=Ce(IV) and Th(IV)). The thermal decomposition of the complexes should be discussed in relation to structure, and the thermodynamic parameters of the decomposition stages were evaluated applying Coats-Redfern and Horwitz-Mitzger methods.  相似文献   

2.
Four new azo ligands, L1 and HL2-4, of sulfa drugs have been prepared and characterized. [MX(2)(L1)(H(2)O)(m)].nH(2)O; [(MX(2))(2)(HL2 or HL3)(H(2)O)(m)].nH(2)O and [M(2)X(3)(L4)(H(2)O)].nH(2)O; M=Co(II), Ni(II) and Cu(II) (X=Cl) and Zn(II) (X=AcO); m=0-4 and n=0-3, complexes were prepared. Elemental and thermal analyses (TGA and DTA), IR, solid reflectance spectra, magnetic moment and molar conductance measurements have accomplished characterization of the complexes. The IR data reveal that HL1 and HL2-3 ligands behave as a bidentate neutral ligands while HL4 ligand behaves as a bidentate monoionic ligand. They coordinated to the metal ions via the carbonyl O, enolic sulfonamide S(O)OH, pyrazole or thiazole N and azo N groups. The molar conductance data reveal that the chelates are non-electrolytes. From the solid reflectance spectra and magnetic moment data, the complexes were found to have octahedral, tetrahedral and square planar geometrical structures. The thermal behaviour of these chelates shows that the water molecules (hydrated and coordinated) and the anions are removed in a successive two steps followed immediately by decomposition of the ligand in the subsequent steps. The activation thermodynamic parameters, such as, E*, DeltaH*, DeltaS* and DeltaG* are calculated from the TG curves applying Coats-Redfern method.  相似文献   

3.
Coordination complexes of transition metals (Co, Ni, Cu, Fe, Cr, Ru, Ir, Mn, and Zn) with 6-methoxy-α-methyl-2-naphthalene acetic acid (Naproxen) and triphenylphosphine have been synthesized and characterized by conductance, elemental analysis, UV-Vis, AAS, and FT-IR spectroscopy. The elemental analyses data reveal the presence of 1:1 (metal : ligand) stoichiometry and the IR data suggest that naproxen functions as a bidentate ligand in coordination with transition metals. The anti-inflammatory assays of these complexes have significant effect.  相似文献   

4.
Metal complexes of Schiff base derived from 2-thiophene carboxaldehyde and 2-aminobenzoic acid (HL) are reported and characterized based on elemental analyses, IR, 1H NMR, solid reflectance, magnetic moment, molar conductance and thermal analysis (TGA). The ligand dissociation as well as the metal-ligand stability constants were calculated pH metrically at 25 degrees C and ionic strength mu=0.1 (1M NaCl). The complexes are found to have the formulae [M(HL)2](X)n.yH2O (where M=Fe(III) (X=Cl, n=3, y=3), Co(II) (X=Cl, n=2, y=1.5), Ni(II) (X=Cl, n=2, y=1) and UO2(II) (X=NO3, n=2, y=0)) and [M(L)2] (where M=Cu(II) (X=Cl) and Zn(II) (X=AcO)). The molar conductance data reveal that Fe(III) and Co(II), Ni(II) and UO2(II) chelates are ionic in nature and are of the type 3:1 and 2:1 electrolytes, respectively, while Cu(II) and Zn(II) complexes are non-electrolytes. IR spectra show that HL is coordinated to the metal ions in a terdentate manner with ONS donor sites of the carboxylate O, azomethine N and thiophene S. From the magnetic and solid reflectance spectra, it is found that the geometrical structure of these complexes are octahedral. The thermal behaviour of these chelates shows that the hydrated complexes losses water molecules of hydration in the first step followed immediately by decomposition of the anions and ligand molecules in the subsequent steps. The activation thermodynamic parameters, such as, E*, DeltaH*, DeltaS* and DeltaG* are calculated from the DrTG curves using Coats-Redfern method. The synthesized ligands, in comparison to their metal complexes also were screened for their antibacterial activity against bacterial species, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus pyogones and Fungi (Candida). The activity data show that the metal complexes to be more potent/antibacterial than the parent Schiff base ligand against one or more bacterial species.  相似文献   

5.
Metal complexes of Schiff base derived from condensation of o-vanilin (3-methoxysalicylaldehyde) and sulfametrole [N(1)-(4-methoxy-1,2,5-thiadiazole-3-yl)sulfanilamide] (H2L) are reported and characterized based on elemental analyses, IR, 1H NMR, solid reflectance, magnetic moment, molar conductance, mass spectra, UV-vis and thermal analysis (TGA). From the elemental analyses data, the complexes were proposed to have the general formulae [M2X3(HL)(H2O)5].yH2O (where M=Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II), X=Cl, y=0-3); [Fe2Cl5(HL)(H2O)3].2H2O; [(FeSO4)2(H2L)(H2O)4] and [(UO2)2(NO3)3(HL)(H2O)].2H2O. The molar conductance data reveal that all the metal chelates were non-electrolytes. The IR spectra show that, H2L is coordinated to the metal ions in a tetradentate manner with ON and NO donor sites of the azomethine-N, phenolic-OH, enolic sulphonamide-OH and thiadiazole-N. From the magnetic and solid reflectance spectra, it is found that the geometrical structures of these complexes are octahedral. The thermal behaviour of these chelates shows that the hydrated complexes losses water molecules of hydration in the first step followed immediately by decomposition of the anions and ligand molecules in the subsequent steps. The activation thermodynamic parameters, such as, E*, DeltaH*, DeltaS* and DeltaG* are calculated from the DrTG curves using Coats-Redfern method. The synthesized ligand, in comparison to their metal complexes also were screened for their antibacterial activity against bacterial species, Escherichia coli, Salmonella typhi, Bacillus subtillus, Staphylococcus aureus and Fungi (Aspergillus terreus and Aspergillus flavus). The activity data show that the metal complexes to be more potent/antimicrobial than the parent Shciff base ligand against one or more microbial species.  相似文献   

6.
The literature data on substituent influence on the CS, CN, NC, NN, and NO stretching frequencies (ν) in the IR spectra and in specific cases on their respective stretching force constants (k) have been analyzed for 28 series of the transition metal complexes. The ν and k values were first established to depend not only on the inductive and resonance effects but on the polarizability of substituents as well. The contribution of the polarizability effect varies from 0 to 57% with the type of series.  相似文献   

7.
Electronic spectra and redox potentials of new mixed-valence RhI-RhIII complexes linked by a cyanide bridge were measured and studied. For these compounds, interaction between rhodium atoms in the molecule is low (a case of fixed valences), and no intervalence transition from RhI to RhIII was observed in the 7000 to 50000 cm–1 range. Some of the complexes in the solid state have additional absorption bands in the diffuse reflectance spectra related to the interaction of orbitals (with appropriate symmetry) of Rh(i) fragments of adjacent complex molecules.Translated fromIsvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 726–732. March, 1996.  相似文献   

8.
A new vic-dioxime ligand containing benzophenone hydrazone units, N′-(benzophenone hydrazone)glyoxime [LH2] has been prepared from benzophenone hydrazone and anti-chloroglyoxime in absolute ethanol. Mononuclear nickel(II), cobalt(II), copper(II), zinc(II), and cadmium(II) complexes were also synthesized. Ligand and complexes were characterized by elemental analyses, FT-IR, 1H NMR, and 13C NMR spectroscopy, magnetic moments, and DTA/TG techniques. On the basis of the magnetic and spectral evidences a square-planar geometry for Ni(II) and Cu(II) complexes, tetrahedral for Cd(II) and Zn(II) complexes, and octahedral for Co(II) complex were proposed. Redox behaviors of ligand and its complexes were also investigated by cyclic voltammetry at the glassy carbon electrode.  相似文献   

9.
Keeping in view the chemotherapeutic of the sulfa-drugs, Schiff base namely 2-thiophene carboxaldehyde-sulfametrole (HL) and its tri-positive and di-positive metal complexes have been synthesized and characterized by elemental analyses, IR, 1H NMR, solid reflectance, magnetic moment, molar conductance, mass spectra, UV-vis and thermal analysis (TGA and DrTG). The low molar conductance values suggest the non-electrolytic nature of these complexes. IR spectra show that HL is coordinated to the metal ions in a tetradentate manner through hetero five-membered ring-S and azomethine-N, enolic sulfonamide-OH and thiadiazole-N, respectively. Zn(II), Cd(II) and UO2(II) complexes are found to be diamagnetic (as expected). The proposed general formulae of the prepared complexes are [M2X4(HL)(H2O)4] (where M=Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II), X=Cl, [Fe2Cl6(HL)(H2O)2], [(FeSO4)2(HL)(H2O)4] and [(UO2)2(HL) (NO3)4].H2O. The thermal behaviour of these chelates shows that the hydrated complexes loss water of hydration in first step in case of uranium complexes followed loss coordinated water followed immediately by decomposition of the anions and ligand molecules in the subsequent steps. The activation thermodynamic parameters, such as DeltaE*, DeltaH*, DeltaS*, and DeltaG* are calculated from the DrTG curves using Coats-Redfern method. The antimicrobial activity of the obtained products was performed using Chloramphenicol and Grisofluvine as standards, indicate that in some cases metallation increase activity than the ligand.  相似文献   

10.
The studied complexes formed by the chelating ion exchanger were characterized by reflectance and infrared spectrometry. The thermal degradation of pure cellulose-hyphan (CH) and its complexes with Hg2+, In3+, Cr3+, Mo4+ and Mn2+ under an atmosphere of air has been studied using thermal gravimetry (TG) and differential thermal analysis (DTG). The results showed that four different stages are accompanying the decomposition of (CH) and its complexes with the studied metals. These stages were found to be affected by the presence of the investigated metal ions. On the bases of the applicability of a non-isothermal kinetic equation it was found to be a first-order reaction with the rate of degradation,k, ranging from 8.3·10?5 to 6.2·10?3 for (CH) and from 1.7·10?5 to 6.6·10?3 s?1 for its complexes. The activation energy,E a, the entropy change, ΔS°, the enthalpy change, ΔH° and Gibbs free energy, ΔG° are calculated by applying the rate theory of the first-order reaction. The effect of the different central metal ions on the calculated thermodynamic parameters is discussed.  相似文献   

11.
Electrospray ionization mass (ESI-MS) spectrometry was used to investigate the nature of metal complexes of alachlor and their dissociations on activation. Ions of the first row transition metal series were employed to react with alachlor and the products were subjected to collision-induced dissociation (CID) for further structural characterization. The formation of diverse complex ions including doubly charged metal/alachlor complexes; [3L + M]2+ and [4L + M]2+ (L: alachlor and M: transition metal ions) were observed depending on the experimental conditions including the tube lens offset voltage (TLOV) and relative concentrations of alachlor and transition metal ions. It is clear that complexation with transition metal ions alters the reactive site of alachlor, promoting the loss of chlorine over the loss of CH3OH that is the major reaction pathway in uncomplexed system. Direct elimination of chlorine from alachlor molecule was confirmed by the use of MnBr2 instead of MnCl2. These evidences clearly illustrate the catalytic activities of the metal ions through insertion mechanism. The function of transition metal ions in complexation was emphasized comparing the fragmentation patterns with those of protonated molecule. A change in the oxidation state of copper from + 2 to + 1 during the dissociation of metal complex was observed in company with elimination of radicals which is specific for the copper complex ions.  相似文献   

12.
Four transition metal complexes with Schiff base and 1,10-phenanthroline, [Cu(L)(phen)]2·C2H5OH (1), [Zn(L)(phen)]2·C2H5OH (2), [Ni(L)(phen)]2·C2H5OH (3), and [Co(L)(phen)]2·C2H5OH (4) (H2L?=?1-((2-hydroxynaphthalen-1-yl)methylene)thiosemicarbazide; phen?=?1,10-phenanthroline) were synthesized and characterized by physico-chemical methods. The crystal structure of 1 was determined by X-ray single-crystal diffraction analysis. 1 crystallizes in the orthorhombic space group Pbca with a?=?15.008(9), b?=?16.100(10), c?=?37.54(2)?Å, V?=?9070(10)?Å3, Z?=?8, GOOF?=?1.002, R 1?=?0.0626, and wR 2?=?0.0912. The fluorescence and urease inhibitory activities of the compounds were tested. The enzymatic activity study indicated that 3 possessed potent inhibition against jack bean urease, with IC50?=?1.2?±?0.1?μM, and about 35 times more than 42.1?±?0.4 acetohydroxamic acid as positive reference. This suggests that inhibitory efficiency of these complexes can be strongly influenced by different transition metal ions.  相似文献   

13.
The electrochemically active polymers have been formed during electro-reduction carried out in solution containing fullerenes, C60 or C70, and transition metal complexes of Pd(II), Pt(II), Rh(III), and Ir(I). In these films, fullerene moieties are covalently bounded to transition metal atoms (Pd and Pt) or their complexes (Rh and Ir) to form a polymeric network. All films exhibit electrochemical activity at negative potentials due to the fullerene cages reduction process. For all studied metal complexes, yields of formation of films containing C70 are higher than yields of electrodeposition of their C60 analogs. C70 /M films also exhibit higher porosity in comparison to C60/M layers. The differences in film morphology and efficiency of polymer formation are responsible for differences in electrochemical responses of these films in acetonitrile containing supporting electrolyte only. C70/M films shows more reversible voltammeric behavior in negative potential range. They also show higher potential range of electrochemical stability. Processes of film formation and electrochemical properties of polymers depend on the transition metal ions or atoms bonding fullerene cages into polymeric network. The highest efficiency of polymerization was observed for fullerene/Pd and fullerene/Rh films. In the case of fullerene/Pd films, the charge transfer processes related to the fullerene moieties reduction in negative potential range exhibit the best reversibility among all of the studied systems. Capacitance performances of C60/Pd and C70/Pd films deposited on the porous Au/quartz electrode were also compared. Capacitance properties of both films are significantly affected by the conditions of electropolymerization. Only a fraction of the film having a direct contact with solution contributes to pseudocapacitance. Capacitance properties of these films also depend on the size of cations of supporting electrolyte. The C70/Pd film exhibits much better capacitance performance comparison to C60/Pd polymer.  相似文献   

14.
4-(Chloroacetyl)diphenyl ether was synthesized from chloroacetyl chloride and diphenyl ether in the presence of AlCl3 as catalyst in a Friedel-Crafts reaction. Then, its keto oxime and dioxime derivatives were prepared. 4-phenoxy-(N-4-chlorophenylamino)phenylglyoxime (H2L) was synthesized from 4-(phenoxy)chlorophenylglyoxime and 4-chloroaniline. Ni(II), Co(II) and Cu(II) complexes of H2L were obtained. The mononuclear Ni(II), Co(II) and Cu(II) complexes of H2L have a metal–ligand ratio of 1:2 and the ligand coordinates through the two N atoms, as do most of the vic-dioximes. The structure of the ligand was identified by FT-IR, 1H NMR, 13C NMR, 13C NMR (APT) spectroscopy and elemental analysis data. The structures of the complexes were characterized on the basis of FT-IR, ICP-AES, UV-Vis, elemental analysis, magnetic susceptibility measurements, and cyclic voltammetry. The electrochemical measurements were obtained by using cyclic voltammetry in DMF solution at room temperature. The electrochemical behaviors of H2L and its complexes showed that the redox process of H2L has one irreversible oxidation wave, whereas the redox processes of the complexes have both oxidation and reduction waves with metal centered.  相似文献   

15.
Ternary Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and UO(2)(II) chelates with tenoxicam (Ten) drug (H(2)L(1)) and dl-alanine (Ala) (HL(2)) and also the binary UO(2)(II) chelate with Ten were studied. The structures of the chelates were elucidated using elemental, molar conductance, magnetic moment, IR, diffused reflectance and thermal analyses. UO(2)(II) binary chelate was isolated in 1:2 ratio with the formula [UO(2)(H(2)L)(2)](NO(3))(2). The ternary chelates were isolated in 1:1:1 (M:H(2)L(1):L(2)) ratios and have the general formulae [M(H(2)L(1))(L(2))(Cl)(n)(H(2)O)(m)].yH(2)O (M=Fe(III) (n=2, m=0, y=2), Co(II) (n=1, m=1, y=2) and Ni(II) (n=1, m=1, y=3)); [M(H(2)L(1))(L(2))](X)(z).yH(2)O (M=Cu(II) (X=AcO, z=1, y=0), Zn(II) (X=AcO, z=1, y=3) and UO(2)(II) (X=NO(3), z=1, y=2)). IR spectra reveal that Ten behaves as a neutral bidentate ligand coordinated to the metal ions via the pyridine-N and carbonyl-O groups, while Ala behaves as a uninegatively bidentate ligand coordinated to the metal ions via the deprotonated carboxylate-O and amino-N. The magnetic and reflectance spectral data confirm that all the chelates have octahedral geometry except Cu(II) and Zn(II) chelates have tetrahedral structures. Thermal decomposition of the chelates was discussed in relation to structure and different thermodynamic parameters of the decomposition stages were evaluated.  相似文献   

16.
In this study, 4-hydroxysalicylaldehyde-p-aminoacetophenoneoxime (LH) was synthesized starting from p-aminoacetophenoneoxime and 4-hydroxysalicylaldehyde. Complexes of this ligand with Co(II), Ni(II), Cu(II) and Zn(II) were prepared with a metal?: ligand ratio of 1?:?2. The ligand and its metal complexes have been characterized by elemental analyses, IR, 1H- and 13C-NMR spectra, magnetic susceptibility measurements and thermogravimetric analyses (TGA).  相似文献   

17.
Metal complexes of omeprazole (OPZ) are prepared and characterized based on elemental analyses, IR, diffuse reflectance, magnetic moment, molar conductance and thermal analyses (TGA and DTA) techniques. From the elemental analyses, the complexes have the general formula [M(L)2]X n [where M = Cr(III) (X = Cl, n = 3), Ni(II) (X = ClO4, n = 2) and Zn(II) (X = Cl, n = 2)], and [M(L)2(H2O)2]X n · yH2O (where M = Fe(III) (X = Cl, n = 3, y = 0), Co(II) (X = Cl or ClO4, n = 2, y = 0–4) and Ni(II) (X = Cl, n = 2, y = 4) and [Cu(L)2]Cl2 · H2O. The molar conductance data reveal that all the metal chelates are 3 : 1 electrolytes (for Cr(III) and Fe(III) complexes) and 2 : 1 (for the remaining complexes). IR spectra show that OPZ coordinates to the metal ions as neutral bidentate with ON donor sites of the pyridine–N and sulphone-O. The magnetic and solid reflectance spectra indicate octahedral (FeCl3, CoCl2, CoClO4 and NiCl2), square planar [Cu(II)] and tetrahedral [Mn(II), Cr(III), NiClO4 and Zn(II)] structures. The thermal behavior of these chelates using thermogravimetric and differential thermal analyses (TGA and DTA) techniques indicate the hydrated complexes lose water of hydration followed immediately by decomposition of the anions and ligand molecules in the successive overlapping OPZ and its metal complexes are screened for antibacterial activity against Escherichia coli, Staphylococcus aureus, Aspergillus flavus and fungi (Candida albicans). The activity data show the metal complexes to be more potent/antibacterial than the parent OPZ ligand against one or more bacterial species.  相似文献   

18.
Transition metal complexes of trimesic acid and hydrazine mixed-ligands with a general formula M(Htma)(N2H4)2, where, M = Mn, Co, Ni, Cu and Zn; H3tma = trimesic acid, have been prepared and characterized by elemental, structural, spectral and thermal analyses. For the complexes, the carboxylate νasym and νsym stretchings are observed at about 1626 and 1367 cm?1 respectively, with Δν between them of ~260 cm?1, showing the unidentate coordination of each carboxylate group. The hydrazine moieties are present as bridging bidentates. Electronic and EPR spectral studies suggest an octahedral geometry for the complexes. All these complexes show three steps of decomposition in TGA/DTA. SEM images of CuO and MnO residues obtained from the complexes show nano-sized clusters suggesting that the complexes may be used as precursors for nano-CuO and nano-MnO preparation. The antimicrobial activities of the prepared complexes, against four bacteria have been evaluated.  相似文献   

19.
Summary A computational approach to conformational analysis is applied to the study of transition metal coordination complexes. The method provides a means of rapidly exploring conformational space without any inherent reliance on energy calculations and is therefore applicable to a wide variety of systems. It has been incorporated into an algorithm which explores the constitutional, configurational and conformational degrees of freedom for a metal ion and a number of potential ligands. The program determines which of the possible coordination complex products could form stable conformations and can therefore be used to rationalise the products obtained from the mixture. The method is illustrated using two cases: the cobalt(III)-triethylenetetramine-glycine system and complexes of diindolopyridine derivatives.Abbreviations en ethylenediamine - trien triethylenetetramine - gly glycine - RMS root mean square - 3D three dimensional  相似文献   

20.
In this work, we aimed to synthesize and characterize a novel tetra-directional ligand, (2E,2′E)-2,2′-((((2-(1,3-bis(4-((E)-(2-carbamothioylhydrazono)methyl)phenoxy)propan-2-ylidene)propane-1,3-diyl)bis(oxy))bis(4,1-phenylene))bis(methanylylidene))bis(hydrazinecarbothioamide) (5), including thiosemicarbazone group and its novel tetra-directional-tetra-nuclear Schiff base complexes. For this purpose, we used 1,4-dibromo-2,3-bis(bromomethyl)but-2-ene (2) as starting material. 4,4′-((2-(1,3-Bis(4-formylphenoxy)propan-2-ylidene)propane-1,3-diyl) bis(oxy))dibenzaldehyde (3) was synthesized by the reaction of an equivalent 1,4-dibromo-2,3-bis(bromomethyl)but-2-ene (2) and 4 equivalents of 4-hydroxybenzaldehyde. Then, compound 5 was synthesized in high yield (86%) by a condensation reaction of compound 3 with thiosemicarbazide (4). Finally, four novel tetra-nuclear Cr(III) or Fe(III) complexes of compound 5 were synthesized. The synthesized compounds were characterized using elemental analyses, 1H NMR, Fourier transform–infrared spectrometry, liquid chromatography–mass spectrometry (ESI+), and thermal analyses. The metal ratios of the prepared complexes were determined using an atomic absorption spectrophotometer. We also investigated their effects on the magnetic behaviors of [salen, salophen, Cr(III)/Fe(III)] capped complexes. The complexes were found to be low-spin distorted octahedral Fe(III) and distorted octahedral Cr(III), all bridged by thiosemicarbazone.  相似文献   

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