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1.
Four new ternary complexes of CuII with l-methionine and the nucleotides 5AMP (adenosine 5-phosphate), 5GMP (guanosine 5-phosphate) and 5IMP (inosine 5-phosphate), and with l-tryptophan and 5AMP, were synthesized and characterized by elemental analysis and i.r. spectroscopy. One ternary complex of NII with l-cysteine and 5IMP was also prepared and characterized. The study of the three ternary compounds of CuII, of general formulae Cu-5NMP-l-methionine, indicates coordination of the phosphate group and of N(7) of the purinic ring. l-Methionine is bound by the carboxylic and amino groups. The ternary complex obtained from a mixture of Cu-5AMP and l-tryptophan is a dimer in which the nucleotide bridges the two copper atoms. In the complex of Ni-5IMP and l-cysteine, the nucleotide seems to bind the metal through the N(7) of the heterocyclic ring, and the l-cysteine is coordinated as a bidentate chelate by the carboxyl and thiol groups. E.s.r. spectra of the copper complexes are in good agreement with the low symmetry structure proposed. The one-electron reduction potentials Ec(Fc+/Fc) (V) of CuII to CuI were established for the four copper complexes from cyclic voltammetry studies. The one-electron oxidation potential Ea(Fc+/Fc+) (V) of NiII to NiIII was also measured for the nickel complex.  相似文献   

2.

In this study, a mononuclear CuL complex was prepared by the use of bis-N,N′-(salicylidene)-1, 3-propanediamine (LH2) and Cu2+ ion. NiCl2 and NiBr2 salt were treated with this complex in dioxanewater medium and two new complexes [(CuL)2NiCl2(H2O)2] and [(CuL)2NiBr2(H2O)2)] with Cu(II)–Ni(II)–Cu(II) nucleus structure were obtained. In addition to this bis-N,N′-(2-hydroxybenzyl)-1,3-diaminopropane (LHH2) was prepared by the reduction of LH2 with NaBH4 in MeOH medium. The treatment of this reduced complex with Cu2+ ion resulted a complex [(CuLH)2CuCl2] with a structure of Cu(II)–Cu(II)–Cu(II). The complexes prepared were characterized by the use of elemental analysis, IR spectroscopy, thermogravimetric and X-ray diffraction methods. The crystal structures of [(CuL)2NiBr2(H2O)2] (СIF file CCDC 1448402) and [(CuLH)2CuCl2] (СIF file CCDC 1448401) complexes were elucidated. It was found that halogen ions are coordinated to terminal Cu2+ ions which are in a distorted square pyramid coordination sphere. It was determined that the central Cu(II), which joins terminal square pyramidal Cu(II), was coordinated only by the phenolic oxygens of the ligand while the central Ni(II) was coordinated by two phenolic oxygens of the organic ligand and two water molecules. These complexes were investigated by XPS and it was found that the terminal and central Cu2+ ions were different in Cu(II)–Cu(II)–Cu(II) complex. Also, the thermal degradation of the CuLH complex unit was observed to exothermic in contrast to the expectations.

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3.
Ion-exchange reactions M2+ Fe3+ and Fe3+ M2+ (M = Mn, Co, Ni, Cu, Zn, Cd) were studied in metal(II) hexacyanoferrate(II) gelatin-immobilized matrices M2[Fe(CN)6] in contact with aqueous FeCl3 solutions and Fe4[Fe(CN)6]3 in contact with aqueous MCl2 solutions. It was shown that in both cases, M2+ was replaced by Fe3+ and Fe3+ was replaced by M2+ to some extent, but no complete replacement was observed in the M2[Fe(CN)6]–FeCl3 or Fe4[Fe(CN)6]3–MCl2 systems under study. No electrophilic substitution Fe3+ Mn2+ was found to occur in any noticeable degree during the contact of Fe4[Fe(CN)6]3 with aqueous MnCl2 solutions even when this contact occurred for 1 h and longer.  相似文献   

4.
Summary MnII, NiII and CuII complexes of (1,3-bis-aminomethyl)-cyclohexane-N,N,N,N-tetrakisbenzimidazole (CDTB) have been prepared and characterized by spectral techniques. The complexes are monomeric and pseudo-octa-hedral, as evidenced by their e.p.r. spectra and analytical data. Parameters 2, 2, 2 and for CuII complexes, and the crystal field splitting parameter (10 Dq) together with the Nephelauxetic ratio (), for NiII complexes, are reported.  相似文献   

5.
6.
Novel complexing processes in the CuII–8-mercaptoquinoline, CuII–5,8-dimercaptoquinoline and CuII–5-thiomethyl-8-mercaptoquinoline systems proceeding in the copper(II)hexacyanoferrate(II) gelatin-immobilized matrix in contact with aqueous solutions of the ligands indicated, have been studied. Under the conditions specified for complexing in the CuII–8-mercaptoquinoline system, only a monomeric water-insoluble coordination compound was formed. In the CuII–5,8-dimercaptoquinoline system, three coordination compounds were formed and, in the CuII–5-thiomethyl-8-mercaptoquinoline system, two such compounds were formed. Conversely, complexing in solution or solid phase results in the formation only coordination compounds in each of the system studied.  相似文献   

7.
Introduction In recent years, much attention has been paid to the research of novel, high-quality nonlinear optical (NLO) crystals, especially those metalorganic complex crystals that can generate high efficient second-harmonic blue-violet light using GaAlAs laser diodes. In order to find this type of crystals, much work has been done in our laboratory on the complex crystals of MM'(SCN)4 and MM'(SCN)·nL, where M = Zn, Cd, Mn; M' = Cd, Hg and L = adduct1-6. A 404.5nm blue-violet lig…  相似文献   

8.
Summary The binuclear metal complexes [Cu(sampn)Co(L)2] (L=bipy, phen), have been prepared by the reaction of sodiumN,N-1,2-propanedisalicylamidatocuprate(II) heptahydrate, Na2[Cu(sampn)] 7H2O, with a divalent metalion, and 2,2-bipyridine or 1, 10-phenathroline. The complexes were characterized by variable-temperature magnetic susceptibility measurements; the results indicate that a weak antiferromagnetic spin-exchange interaction operates between the metal ions.  相似文献   

9.
Abstract

The coordination in aqueous solution of 4-chloro-1,2-phenylenediamine-N',N',N',N'-tetraacetic acid (4-Cl-o-PDTA) with Be(II) and with the transition metal cations cobalt(II), nickel(II) and copper(II) was reported in earlier publications.1,2 In this note a study is presented of the coordination in aqueous solution (25°C, 1 = 0.1 M in KC1) of 4-CI-o-PDTA acid with magnesium(II), calcium(II), strontium(II), barium(II), zinc(II) and cadmium(II).  相似文献   

10.
Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) complexes of the type Na4[ML(H2O)2] of the ligand, 3,3′-bis[N,N-di(carboxymethyl)-aminomethyl]-o-cresol sulphonphthalein (Xylenol Orange, Na4H2L), have been synthesized and characterized by different physico-chemical (elemental analyses, solubility, electrolytic conductances, magnetic susceptibility measurements) and spectral (u.v.-vis, i.r., e.s.r., and powder X-ray diffraction) techniques for their structure determination. The data suggest 1?:?1 (M?:?L) compositions and octahedral geometries around M(II) except for Cu(II). Antifungal activity of the complexes measured against ten fungi show significant activity against Alternaria brassicicola, Alternaria solanai, Cercospora species and Helminthosporium oryzae and moderate antifungal activity against Curvularia species, Curvularia lunata, Curvularia penniseti, Colletotrichum capsici, Aspergillus niger, Aspergillus flavus Erysiphae pisi and Fusarium udum fungi.  相似文献   

11.
本文为了进一步了解具有生物活性的木杨醛缩氨基硫脲在溶液中与常见金属离子的作用本质, 在半微量恒温滴定池上用PH电位法研究了该物质与铜(II)、锌(II)、镍(II)、钴(II)、锰(II)及镉(II)等二价金属离子的配位作用.  相似文献   

12.
房喻  孙作民 《化学学报》1989,47(5):487-490
本文为了进一步了解具有生物活性的木杨醛缩氨基硫脲在溶液中与常见金属离子的作用本质, 在半微量恒温滴定池上用PH电位法研究了该物质与铜(II)、锌(II)、镍(II)、钴(II)、锰(II)及镉(II)等二价金属离子的配位作用.  相似文献   

13.
Summary The reactions of manganese(II), cobalt(II) and nickel(II) acetates (1 mole) with antipyrine-4-azo--ethylcyanoacetate (HL1) and antipyrine-4-azo--acetylacetone (HL2) (1 mole) produce complexes of the M(L)2 type. K2PdCl4 (1 mole) reacts with HL1 and HL2 (1 mole) to yield complexes of the general formula PdLCl, the ligands behaving as monobasic tridentates. The electronic spectral and magnetic data show the complexes to be high-spin octahedral, whereas the palladium(II) complexes are diamagnetic square planar. The complexes were characterized by elemental analyses, conductance measurements and i.r. and electronic spectra as well as magnetic susceptibility measurements and thermal (t.g.a. and d.t.a.) analysis.Nuclear Material Authority.  相似文献   

14.
A project related to the crystal engineering of hydrogen-bonded coordination complexes has been initiatied and some of our first results are presented here. The compounds [Mn(DMU)6](ClO4)2 (1), [Ni(DMU)6](ClO4)2 (2), [Cu(OClO3)2(DMU)4] (3) and [Zn(DMU)6](ClO4)2 (4) have all been prepared from the reaction of N,N-dimethylurea (DMU) and the appropriate hydrated metal perchlorate salt. Crystal structure determinations of the four compounds demonstrate the existence of [M(DMU)6]2+ cations and ClO4 counterions in (1), (2) and (4), whereas in (3) monodentate coordination of the perchlorate groups leads to molecules. The [M(DMU)6]2+ cations and ClO4 anions self-assemble to form a hydrogen-bonded one-dimensional (1D) architecture in (1) and different 2D hydrogen-bonded networks in (2) and (4). The hydrogen bonding functionalities on the molecules of (3) create a 2D structure. The complexes were also characterised by room-temperature effective magnetic moments and i.r. studies. The data are discussed in terms of the nature of bonding and the known structures.  相似文献   

15.
Abstract

The title complex has been prepared and its structure determined by X-ray diffraction. The complex crystallizes in space group C2/c with a = 26.892(5), b = 10.479(4), c = 14.179(2) Å, β = 98.59(2)°. Isonicotinate anions bridge adjacent Cu(II) atoms through the pyridine N atom and the carboxyl O atom to form zigzag polymeric chains along the b axis. The carboxyl group of the isonicotinate anion coordinates to the Cu(II) atom as a unidentate. Based on the molecular structure the infrared spectrum is discussed.  相似文献   

16.
Complexes of Co(II), Ni(II), Cu(II), and Zn(II) with N,N′-(aldose)2–thiocarbohydrazide (LH2) were synthesized, isolated as solid products and characterized by analytical means as well as by spectral techniques, FTIR, 1H NMR, EPR, UV spectroscopy, and CD. All the metal ions formed M[LH]X complexes. Molar conductance values in DMF indicate non-electrolytic complexes. In DMSO with tetramethylammonium chloride supporting electrolyte, the copper complex displays irreversible cyclic voltammetric responses with E p near ?0.621 and 0.461 V versus Ag/AgCl at scan rate of 0.1 V s?1. Probable structures for the complexes are proposed.  相似文献   

17.
A new 1,2-diamine ligand, N,N-bis(2-hydroxyethyl)stilbenediamine (L), has been prepared by reduction of the condensation product of benzaldehyde with 2-aminoethanol with Al amalgam. Mononuclear complexes of the [CuL(H2O)]X2 type where X=Cl or AcO with CuII and PdLCl2 with palladium(II) have been prepared and characterized by elemental analysis and i.r., u.v.–vis. or 1H-n.m.r. spectroscopy.  相似文献   

18.
A new mononuclear Zn(II) complex, [ZnL(HOAc)] (1) (H2L = 6,6′-diethoxy-2,2′-[1,2-ethylenedioxybis(nitrilomethylidyne)]diphenol), was synthesized by reaction of H2L and Zn(II) acetate under solvothermal conditions. Complex 1 acts as a metallohost possessing a pentadentate O5 donor. Complex 1 molecules bonded to one Sr(II) or Ba(II) form two new hetero-trinuclear complexes, [(ZnL)2M(OAc)2] (M = Sr (2), Ba (3)). In 2 and 3, Zn(II) ions are 5-coordinate, but the Sr(II) or Ba(II) ion is 10-coordinate by four μ-phenolic oxygens from two L2? units, four oxygens from four ethoxy groups and two oxygens from two μ-acetato ligands. Furthermore, 13 exhibit blue emissions with the maximum emission wavelengths λmax = 477, 500, and 471 nm when excited at 360 nm.  相似文献   

19.
Using spectrophotometry we found that ligand exchange in the systems of H2L-[MX2]-DMF, where M denotes Co2+, Cu2+, and Zn2+; X means Acac?, Val?, dpm?; Hdpm? is hexamethyldipyrrolylmethene, H2L is bis(2,4,7,8,9-pentamethyldipyrrolylmethene-3-yl)methane, proceeds through successive stages of formation of hetero- and homoleptic binuclear complexes. Conventional sensitivity of the spectrophotometric determination of Co2+, Cu2+, and Zn2+ reaches 10?9 M.  相似文献   

20.
New complexes of type [M(HL)(CH3COO)(OH2)m]·nH2O (where M:Co, m = 2, n = 2; M:Ni, m = 2, n = 1.5; M:Zn, m = 0, n = 2.5 and M:Cd, m = 0, n = 0; H2L:5-bromo-N,N′-bis-(salicylidene)-o-tolidine) have been synthesized and characterized by microanalytical, IR, UV–Vis-NIR and magnetic data. Electronic spectra of Co(II) and Ni(II) complexes are characteristic for an octahedral stereochemistry. The IR spectra indicate a chelate coordination mode for mono-deprotonated Schiff base and a bidentate one for acetate ion. The thermal transformations are complex according to TG and DTA curves including dehydration, acetate decomposition and oxidative degradation of the Schiff base. The final product of decomposition is the most stable metallic oxide.  相似文献   

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