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1.
Clegg JK Bray DJ Gloe K Gloe K Jolliffe KA Lawrance GA Lindoy LF Meehan GV Wenzel M 《Dalton transactions (Cambridge, England : 2003)》2008,(10):1331-1340
Uncharged complexes, formulated as trimeric metallocycles of type [M3(L(1))3(Py)6] (where M = cobalt(II), nickel(II) and zinc(II) and L(1) is the doubly deprotonated form of a 1,4-phenylene linked bis-beta-diketone ligand of type 1,4-bis(RC(O)CH2C(O))C6H4 (R = t-Bu)) have been synthesised, adding to related, previously reported complexes of these metals with L(1) (R = Ph) and copper(ii) with L(1) (R = Me, Et, Pr, t-Bu, Ph). New lipophilic ligand derivatives with R = hexyl, octyl or nonyl were also prepared for use in solvent extraction experiments. The X-ray structures of H2L(1) (R = t-Bu) and of its trinuclear (triangular) nickel(II) complex [Ni3(L(1))3(Py)6].3.5Py (R = t-Bu) are also presented. Electrochemical studies of H2L(1), [Co3(L(1))3(Py)6], [Ni3(L(1))3(Py)6], [Cu3(L(1))3], [Zn3(L(1))3(Py)6] and [Fe4(L(1))6] (all with R = t-Bu) show that oxidative processes for the complexes are predominantly irreversible, but several examples of quasireversible behaviour also occur and support the assignment of an anodic process, seen between +1.0 and +1.6 V, as involving metal-centred oxidations. The reduction behaviour for the respective metal complexes is not simple, being irreversible in most cases. Solvent extraction studies (water/chloroform) involving the systematic variation of the metal, bis-beta-diketone and heterocyclic base concentrations have been performed for cobalt(II) and zinc(II) using a radiotracer technique in order to probe the stoichiometries of the respective extracted species. Significant extraction synergism was observed when 4-ethylpyridine was also present with the bis-beta-diketone ligand in the chloroform phase. Competitive extraction studies demonstrated a clear uptake preference for copper(II) over cobalt(II), nickel(II), zinc(II) and cadmium(II). 相似文献
2.
Summary The 4-hydroxyphenylthiocarboxyhydrazide (Hoth) ligand has been characterized by i.r.,1H and13C spectral studies. Its metal complexes with FeII, CoII,III, NiII, CuII and ZnII have been prepared and characterized on the basis of elemental analyses, molar conductance, magnetic susceptibility. Mössbauer, visible, e.s.r., i.r.,1H and13C n.m.r. spectral studies. The bonding and stereochemistry of the complexes are discussed. Hoth and its CuII complexes have been screened towards bacteria, viruses and fungi. 相似文献
3.
El-Sawaf Ayman K. West Douglas X. El-Saied Fathy A. El-Bahnasawy Ramadan M. 《Transition Metal Chemistry》1998,23(5):649-655
4–Formylantipyrine N(4)-antipyrinylthiosemicarbazone and its metal complexes have been synthesized and characterized. Elemental analyses, molar conductivities, magnetic measurements and spectral (i.r., electronic, n.m.r., e.s.r.) studies have been used to characterize the complexes. The i.r. spectra show that the thiosemicarbazones behave as bidentate (NS) or tridentate ligands (ONS), either in the thione or thiolato form. Stereochemistries are proposed for the complexes on the basis of both spectral and magnetic studies. 相似文献
4.
El-Sawaf Ayman K. West Douglas X. El-Saied Fathy A. El-Bahnasawy Ramadan M. 《Transition Metal Chemistry》1998,23(5):565-572
2–Formylpyridine N(4)-antipyrinylthiosemicarbazone and its metal complexes have been synthesized and characterized. Elemental analyses, molar conductivities, magnetic measurements and spectral (i.e., i.r., electronic, n.m.r. and e.s.r.) studies have been used to characterize the complexes. The i.r. spectra show that the thiosemicarbazones behave as bidentate or tridentate ligands either in the thione or thiolato form. Ligand field parameters have been calculated and the proposed stereochemistries are based on the various physical and spectral methods. 相似文献
5.
The effects of pH have been examined on the extraction of the title ions by complexing with LIX-64N in kerosene. The extent of metal extraction as a function of pH is: Cu(II) < Fe(III) < Ni(II) < Zn(II) < Co(II). Stripping of all metal ions but cobalt with sulphuric acid from loaded kerosene complexing solutions is easily accomplished. Oxidation of Co(II) to Co(III) in the organic phase prevents stripping of this metal ion. 相似文献
6.
1-Isonicotinoyl-4-benzoyl-3-thiosemicarbazide (IBtsc) and its CrIII, MnII, FeIII, CoII, NiII, CuII and ZnII complexes have been prepared and characterized by elemental analyses, magnetic susceptibility measurements, u.v.–vis., i.r., n.m.r. and FAB mass spectral data. The room temperature e.s.r. spectra of the CrIII, FeIII and CuII complexes yield values, characteristic of octahedral, tetrahedral and square-planar complexes, respectively. The Mössbauer spectra of [Fe(IBtsc-H)Cl2] at room temperature and at 78 K suggest the presence of high-spin FeIII. The NiII, CrIII and CuII complexes show semiconducting behaviour in the solid state, but the ZnII complex is an insulator at room temperature. IBtsc and its soluble complexes have been screened against several bacteria, fungi and tumour cell lines. 相似文献
7.
The self-assembly of unsymmetrical metal ligands from simpler components circumvents complex synthetic approaches. We show herein how a recently developed three-component assembly to create tripicolylamine-like ligands can be extended to the use of azides rather than pyridines. Substituent effects, metal dependence, and reversibility of the assembly are explored. Further, we show that the extent of assembly directly correlates with the differential binding of the templating metals between dipicolylamine-like and tripicolyamine-like ligands. 相似文献
8.
Vettaikaranpudur G. Gnanasoundari Karuppannan Natarajan 《Transition Metal Chemistry》2005,30(4):433-438
A series of new β-diketonato complexes have been synthesized from the reactions of iron(III), cobalt(II), nickel(II) and copper(II) Ph3P complexes with β-diketones (acetylacetone, benzoylacetone and dibenzoylmethane). All the complexes have been characterized by elemental analyses, spectral studies (i.r., electronic., magnetic., e.p.r., 1H-n.m.r.) and cyclic voltammetry. The new complexes have been used as catalysts for aromatic coupling and oxidation reactions. Higher catalytic activity has been observed for the nickel(II) complexes compared to the other complexes. 相似文献
9.
Summary Biacetyldihydrazone (BdH) complexes [M(BdH)3](ClO4)2 (M=CoIIor CuII) and [M(BdH)3](NO3)2,3 (M = NiIIor FeIII) have been prepared and characterized by chemical analysis, conductance measurements, electronic, i.r. and e.p.r. spectral studies and magnetic subsceptibilities measurements. A mononuclear octahedral configuration is proposed for all complexes studied. 相似文献
10.
《Journal of Coordination Chemistry》2012,65(6):1063-1070
Transition metal complexes [Fe(HL)2]Cl3 ? 1.5H2O (1), [Co(L)2] ? ClO4 ? H2O (2), Ni(HL)2(ClO4)2 ? 2H2O (3), Zn(HL)L ? BF4 ? 2H2O (4), and Cd(HL)2(ClO4)2 ? 2H2O (5), where HL = C7H9N5S, 2-acetylpyrazine thiosemicarbazone, have been synthesized. Complex 2 was characterized by elemental analysis, infrared spectra, mass spectra, and single-crystal X-ray diffraction. Preliminary in vitro screening showed that 1, 4, and 5 exhibit higher antitumor activity than 2 and 3 against K562 leucocythemia cancer cell line. 相似文献
11.
Dikonda S. Rani Parupalli V. A. Lakshmi Vuppalapati Jayatyagaraju 《Transition Metal Chemistry》1994,19(1):75-77
Summary Manganese(II), iron(III), cobalt(II), nickel(II), copper(II) and zinc(II) complexes of a new multidentate oxygen-nitrogen donor, bis(N-salicylidene)-2,3-dihydrazino-1,4-quinoxaline (H2BSDHQ) were prepared and characterised by elemental analysis, conductance, thermal, spectral and magnetic data. H2BSDHQ deprotonates to give a dibasic ONNO donor set in a trivalent iron(III) complex, which binds to the divalent metal ions in a bis-tridentate fashion, using two monobasic ONN donor sets, and resulting in polymeric complexes. Octahedral geometries are proposed for all these complexes, and preliminary studies show that they possess potential antimicrobial activity. 相似文献
12.
Acetylsalicylhydroxamic acid (AcSHA) was prepared and characterized. Its pKa value was determined as 7.78. Solid metal complexes of AcSHA were also prepared and characterized by elemental analysis, electronic and i.r. spectroscopies, and by magnetic moment measurements. The shift of both hydroxamic and acetyl carbonyl vibrations to lower frequencies clearly indicates that AcSHA is bonded through oxygen atoms to the metal ions as a tridentate ligand. On the basis of the experimental data, structures for the complexes are purposed. 相似文献
13.
Complexes of CrIII, MnII, FeIII, CoII, NiII and CuII containing a macrocyclic pentadentate nitrogen–sulphur donor ligand have been prepared via reaction of a pentadentate ligand (N3S2) with transition metal ions. The N3S2 ligand was prepared by [1 + 1] condensation of 2,6-diacetylpyridine with 1,2-di(o-aminophenylthio(ethane. The structures of the complexes have been elucidated by elemental analyses, molar conductance, magnetic susceptibility measurements, i.r., electronic and e.p.r. spectral studies. The complexes are of the high spin type and are six-coordinate. 相似文献
14.
El-Saied Fathy A. El-Asmy Ahmed A. Kaminsky Werner West Douglas X. 《Transition Metal Chemistry》2003,28(8):954-960
CoII,III, NiII, and CuII complexes of new dehydroacetic acid N4-substituted thiosemicarbazones have been studied. The substituted thiosemicarbazones, N4-dimethyl-(DA4DM), N4-diethyl-(DA4DE), 3-piperidyl-(DApip) and 3-hexamethyleneiminyl-(DAhexim), when reacted with the metal chlorides, produced two CoII complexes, [Co(DA4DE)Cl2] and [Co(DAhexim)2Cl2]; two CoIII complexes, [Co(DA4DM-H)2Cl] and [Co(DApip-H)(DApip-2H)]; a paramagnetic NiII complex, [Ni(DAhexim)(DAhexim-H)Cl]; three diamagnetic NiII complexes, [Ni(DA4DM-H)Cl], [Ni(DA4DE-H)Cl] and [Ni(DApip-H)Cl]; and four CuII complexes with the analogous stoichiometry of the latter three NiII complexes. These new thiosemicarbazones have been characterized by their melting points, as well as i.r., electronic and 1H-n.m.r. spectra. The metal complexes have been characterized by i.r. and electronic spectra, and when possible, n.m.r. and e.s.r. spectra, as well as elemental analyses, molar conductivities, and magnetic susceptibilities. The crystal and molecular structure of the four-coordinate CuII complex, [Cu(DAhexim-H)Cl] has been determined by single crystal X-ray diffraction and the anionic ligand coordinates via an oxygen of the dehydroacetic acid and the thiosemicarbazone moiety's imine nitrogen and thione sulfur. 相似文献
15.
Benjamin Berisso 《Mikrochimica acta》1970,58(5):965-969
Summary The complex FeI3·3 C9H7N has been verified through topochemical reactions leading to known microcrystalline products. Using the same technique, Fe(III), Co(II), and Ni(II) can be detected in mixtures at concentrations of 1 to 0.01% within an hour.
Presented at the 8th Pan-American Congress of Pharmacy and Biochemistry, November 30-December 7, 1969, Caracas, Venezuela. 相似文献
Zusammenfassung Die Zusammensetzung des Komplexes FeJ3 · (C9H7N)3 wurde durch topochemische Kristallfällungsreaktionen erwiesen. In gleicher Weise lassen sich Fe(III), Co(II) und Ni(II) in Konzentrationen zwischen 0,01 und 1% innerhalb 1 Stunde nebeneinander nachweisen.
Presented at the 8th Pan-American Congress of Pharmacy and Biochemistry, November 30-December 7, 1969, Caracas, Venezuela. 相似文献
16.
S. Sadaoui-Kacel S. Zaater N. Bensouilah S. Djebbar 《Journal of Structural Chemistry》2016,57(8):1519-1530
Novel transition metal complexes with the repaglinide ligand [2-ethoxy-4-[N-[1-(2piperidinophenyl)-3-methyl-1-1butyl] aminocarbonylmethyl]benzoic acid] (HL) are prepared from chloride salts of manganese(II), iron(III), copper(II), and zinc(II) ions in water-alcoholic media. The mononuclear and non-electrolyte [M(L)2(H2O)2]?nH2O (M = Mn2+, n = 2, M = Cu2+, n = 5 and M = Zn2+, n = 1) and [M(L)2(H2O)(OH)]?H2O (M = Fe3+) complexes are obtained with the metal:ligand ratio of 1:2 and the L-deprotonated form of repaglinide. They are characterized using the elemental and molar conductance. The infrared, 1H and 13C NMR spectra show the coordination mode of the metal ions to the repaglinide ligand. Magnetic susceptibility measurements and electronic spectra confirm the octahedral geometry around the metal center. The experimental values of FT-IR, 1H, NMR, and electronic spectra are compared with theoretical data obtained by the density functional theory (DFT) using the B3LYP method with the LANL2DZ basis set. Analytical and spectral results suggest that the HL ligand is coordinated to the metal ions via two oxygen atoms of the ethoxy and carboxyl groups. The structural parameters of the optimized geometries of the ligand and the studied complexes are evaluated by theoretical calculations. The order of complexation energies for the obtained structures is as follows: The redox behavior of repaglinide and metal complexes are studied by cyclic voltammetry revealing irreversible redox processes. The presence of repaglinide in the complexes shifts the reduction potentials of the metal ions towards more negative values.
相似文献
$$Fe(III) complex < Cu(II) complex < Zn(II) complex < Mn(II) complex.$$
17.
Karen A. Ketcham John K. Swearingen Alfonso Castieiras Isabel Garcia Elena Bermejo Douglas X. West 《Polyhedron》2001,20(28):19-3273
Reduction of 2-cyanopyridine by sodium in the presence of 3-piperidylthiosemicarbazide produces 2-pyridineformamide 3-piperidylthiosemicarbazone, HAmpip. Complexes with iron(III), cobalt(II,III) copper(II) and zinc(II) have been prepared and characterized by molar conductivities, magnetic susceptibilities and spectroscopic techniques. In addition, the crystal structures of HAmpip, [Fe(Ampip)2]ClO4, [Cu(HAmpip)Cl2]·CH3OH and [Zn(HAmpip)Br2]·C2H6SO have been determined. Coordination is via the pyridyl nitrogen, imine nitrogen and thiolato or thione sulfur when coordinating as the anionic or neutral ligand, respectively. 相似文献
18.
Summary Complexes of formula [MCl3(glyH)3] (M=Ti, V and Fe) [CrCl3(glyH)2H2O], [MCl2(glyH)2(H2O)2] (M=Co and Cu) and [NiCl2(glyH)3H2O] have been prepared and characterized by potentiometric curves, chemical analysis, magnetic properties, i.r. and electronic spectral data. 相似文献
19.
《Journal of Coordination Chemistry》2012,65(13):1131-1139
Complexes of sulfamethoxydiazine with Cu(II), Zn(II), Ni(II), Cd(II), Cr(III) and Fe(III) have been synthesized and characterized on the basis of conductivity measurements, elemental analyses, UV, IR, 1H?NMR and thermal studies. It is shown that sulfamethoxydiazine behaves as a bidentate ligand, binding the metal ion through the sulfonyl oxygen and sulfonamide nitrogen. In vitro susceptibility tests of these complexes against Escherichia coli, Bacillus subtilis, Proteus vulgaris and Staphylococcus aureus were carried out. The results show that the antibacterial activities of the complexes of Zn(II), Cu(II), Cr(III) and Fe(III) are, in general, stronger than that of sulfamethoxydiazine, while the complexes of Cd(II) and Ni(II) are less active. 相似文献
20.
Athinoula L. Petrou Maria V. Koromantzou John M. Tsangaris 《Transition Metal Chemistry》1991,16(1):48-52
Summary The preparation of complexes of 3,4-dihydroxyphenylpropoionic acid (hydrocaffeic acid): K2[Cu2(hydcafH)2-Cl2]·2KCl·2MeOH, K2[Co(hydcafH)2]·2KCl, K2[Ni2(hydcafH)2Cl2]·2KCl·2MeOH and Fe2 (hydcafH)2Cl2·2KCl·2H2O was achieved. Spectroscopic and magnetic studies are commensurate with tetrahedral structures for the prepared complexes in which the catechol-like coordination is present. 相似文献