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1.
Abstract

This review summarizes the data for over nine hundred dimeric Cu(II) coordination compounds. There are several types of the bridges, from which doubly bridges by far prevail. The most common ligands are O? and N? donors. From the stereochemical point of view, a square-pyramidal arrangement with different degrees of distortion about Cu(II), is the most common. Several relationships were found between the Cu-Cu distances and the Cu-L-Cu bridge angle and the type of bridging, between the intra-ligand L-Cu-L ring angles and coordination numbers.  相似文献   

2.
Abstract

This review classifies almost 600 polymeric Cu(II) compounds. The various geometries are found in increasing number in the order: four-(mostly square-planar) ? five- (mostly square-pyramidal) ? six-coordinate (mostly tetragonal-bipyramidal). The most common ligands are oxygen and nitrogen atoms. The ligands range from mono- to undecadentate. In most examples, apical positions are occupied by oxygen-donor ligands. In general, the mean Cu-L(equatorial) bond length is shorter than the respective Cu-L(apical) bond length. The shortest Cu-Cu distance in the series of four-coordinate derivatives is 2.95 Å, five-coordinate 2.652(2) Å and six-coodinate 2.977(2) Å. Several relationships between the various structural parameters were found and are discussed.  相似文献   

3.
Abstract

This review summarizes the data for over five hundred and fifty six-, seven- and eight-coordinate Cu(II) coordination compounds. The six-coordinate derivatives are mostly distorted tetragonal (elongation along a single C 4 axis). The seven-coordinate derivatives are only penta-gonal-bipyramidal with different degrees of distortion and the eight-coordinate complexes are dodecahedral. The most common ligands are O- and N-donors. There is a trend for the Cu-L distance to increase with covalent radius of the coordinated atom and also increasing coordination number. In general, Cu(II) compounds “prefer” a monoclinic class and are blue or green. Several relationships were found and discussed. The data are compared and discussed with those of four- and five-coordinate Cu(II) compounds.  相似文献   

4.
Abstract

Zinc has a relatively low abundance in nature (10?6 of the earth's crust) but the chemistry of zinc compounds has been extensively investigated, and the relation-ships between structure and biomedical activity are of major importance. Zinc appears to bc one of the more biologically important metals,1 second only to iron among the heavy metals (i.e. excluding sodium, potassium, magnesium and calcium).  相似文献   

5.
Abstract

The new 1,2-dithiolene, 1,4-butanediyldithioethylene-1,2-dithiolate, has been isolated. In addition, new monoanionic bis-complexes with nickel and copper have been prepared and isolated. The formal Ni(III) complex crystallizes in the orthorombic space group, Pbca, with a = 9.762(9), b = 12.53(2), and c = 23.166(3) Å, with 4 molecules in the unit cell. The structure was refined to an R = 9.01% (Rw = 8.95%). The formal Cu(III) complex crystallizes in the monoclinic space group, C2/c, with a = 25.567(6), b = 8.011(3), c = 14.504(3) Å, and β = 106.17(2)° with 4 molecules in the unit cell. The structure refined to R = 4.2% with R w = 4.3%. Comparisons to similar 1,2-dithiolenes suggest this ligand produces only modest structural and electronic differences when compared to the 1,3-propanediyldithioethylene-1,2-dithiolate complexes. The oxidation (to a neutral complex) and reduction (to a dianion) for the Ni(III) and Cu(III) complexes show large differences from those of maleonitriledithiolate. Other physical data are presented as well.  相似文献   

6.
Abstract

A number of oxo-centred trinuclear complexes have been obtained, of general formula [M3O(OOCR)6L3]X (R?H, CH3; M?Cr(III), Fe(III); L=pyridine, 4-picoline; X?NO? 3, ClO? 4). The behaviour of these compounds in absolute methanol and in dimethylsulphoxide was investigated by the conductometric method. Dissociation constants of the complexes were determined. Molar conductivities and solvodynamic radii of the cations were also evaluated. It has been shown that the cations do not undergo solvation to any measurable extent.  相似文献   

7.
8.
铜(Ⅱ)络合纤维的配位结构与抗菌性   总被引:5,自引:0,他引:5  
用蚕丝、粘胶纤维素、聚乙烯醇纤维在铜氨溶液中的多相配位取代反应制备了铜(Ⅱ)络合纤维.用电子自旋共振(ESR)波谱等研究了铜(Ⅱ)络合纤维的配位结构.对金黄色葡萄球菌的抗菌实验表明:铜(Ⅱ)络合纤维的配位结构越不稳定抗菌性越强,但耐洗性将会下降.在此基础上设计了配位结构稳定性适中的柠檬酸修饰纤维素铜(Ⅱ)络合纤维  相似文献   

9.
Abstract

The grinding of a 2: 1 molar ratio mixture of isonitrosoacetylacetone and 1,3-diaminopropan-2-ol led to formation of the tribasic ligand (H3L), (1) with two oxime groups and a flexible alcoholic backbone. The 1:2 molar ratio reaction of (1) with CuX2 produced the planar dinuclear complexes LCu2(X) nH2O; × = acetate (2), phenylacetate (3), formate (4), monochloroacetate (5), dichloroacetate (6), trichloroacetate (7), benzoate (8), and p-hydroxybenzoate (9); n = 1 for (2) and (8); n = 2 for (3)-(7); and n = 4 for (9). The copper(II) ions are bridged by the carbox-ylate and the alcoholic oxygen. The strong antiferromagnetic interactions in (2)-(9) are impeded in (5)-(7) by the chloroacetate bridge withdrawing electron density from the carboxylate. The latter bridge is replaced by picrate in the 1:1 molar ratio reaction of (2) with picric acid (10). The 1:1 molar ratio reaction of (1) with copper(II) acetate produced the tetranuclear [HLCu]2[LCu2(OAc)] 5H2O (11), whereas the 2:1 molar ratio reaction, similar to the reaction which led to (8), produced HLCu (12). The latter complex reacted (1:1 molar ratio) with either copper(ll) acetate or nickel(II) acetate to produce complexes (2) and the heterodinuclear LNi-Cu(OAc) 2H2O (13), respectively. Similar reactions with (11) gave the same complexes (2) and (13). The acid adducts of (9) with p-hydroxybenzoic acid (14) and LCu2(X)-HX (15); × = p-aminobenzoic acid were isolated. The cobalt(II) analogue of the mononuclear (12), HLCo 2H2O (16) was obtained from the 1:1 molar reaction of (1) with cobalt(II) acetate. The supramolecular structure of (11), (12) and (16) took place via intermolecular hydrogen bonding of the alcoholic proton with the oximato oxygen of the adjacent molecule which mediated electron density and allowed for a magnetic exchange interaction. The suggested structures of the ligand and metal complexes are in accordance with analytical, spectral and magnetic moment data.  相似文献   

10.
Abstract

The reaction of pyridine-2-carbonitrile (2-CNpy) with 2-amino-2-hydroxymethyl-1,3-propanediol (L1) and 2-amino-2-methyl-1-propanol (L2) in methanolic solutions of anhydrous copper(II) chloride at room temperature led to the formation of solid complexes containing 2-(2-pyridinyl)-4,4-bis(hydroxynmethyl)-2-oxazoline (pyoxaL1) and 2-(2-pyridinyl)-4,4-dimethyl-2-oxazoline (pyoxaL2), respectively. With copper(II) bromide instead of copper(II) chloride, along with the oxazoline complexes, the complex dibromo-bis(pyridine-2-carbox-amidine)copper(II) was isolated. Under several hour reflux, the complexes dihalogenobis(pyridine-2-carboxamidine)copper(II) are the only isolable products both for chloride and bromide starting salts. The stereochemistry of the complexes and the mode of ligand coordination have been determined by spectroscopic and conductometric measurements. The crystal structure of bromobis[(2-(2-pyridinyl)-4,4-dimethyl)-2-oxazoline]copper(II) bromide hydrate was solved by X-ray diffraction techniques. The mechanism of 2-CNpy transformation to the final products is proposed.  相似文献   

11.
Abstract

Nickel(II) complexes with a combination of trithiocyanuric acid and diamines or triamines of composition [Ni(aepa)(ttcH)(H2O)], [Ni(dien)(ttcH)(H2O)], [Ni(dpta)(ttcH)(H2O)] H2O, [Ni(phen)2(ttcH)]H2O, [Ni(phen)3](ttcH)-5H2O and [Ni(1,2-pn)3](ttcH)-H2O (aepa = N-(2-aminoethyl)-1,3-propanediamine,dien = diethylenetriamine,dpta = dipropylenetnamine, phen = 1,10-phenanthroline, 1,2-pn = 1,2-diaminopropane. ttcH3 = trithiocyanuric acid) have been prepared. The compounds have been characterized by means of elemental analysis, IR and electronic spectroscopies and magnetochemical measurements. Selected complexes were studied by thermal analysis. The compounds can be characterized as distorted octahedral Ni(II) complexes. It was found that the trithiocyanuric dianion can act either as a bidentate ligand or be situated out of the coordination sphere of nickel. The crystal and molecular structure of [Ni(dpta)(ttcH)(H2O)] H2O was determined. Crystals are monoclinic, space group P21/n, with a = 20.316(4), b = 7.967(2), c = 21.401(4) Å, β = 99.23(3)°, K=3419.1(13)Å3, Z = 4, T = 293 K. The nickel(II) atom is six-coordinated by three nitrogen atoms from dipropylene-triamine, nitrogen and sulphur from trithiocyanuric acid, and an oxygen atom from a water molecule in a distorted octahedral geometry.  相似文献   

12.
Abstract

Solubilities and derived transfer chemical potential trends are reported for several tris(hydroxamato)-aluminium(III) and iron(III) complexes in methanol-water and in t-butylalcohol-water solvent mixtures. These trends are discussed in terms of hydrophilic and hydrophobic characteristics of the peripheries of these complexes.  相似文献   

13.
Abstract

The preparation and properties of new complexes containing the biometals Fe(III), Co(II) and Ni(II) coordinated to the anti-inflammatory drug Suprofen are reported. The elemental analyses, together with the magnetic and thermal behavior and electronic, IR and Raman spectra, indicated the following stoichiometries for the latter two complexes: [M(Sup)2(H2O)4]. For the Fe(III) complex, the generation of a dinuclear species may be proposed on the basis of 57Fe Mössbauer measurements.  相似文献   

14.
Abstract

Tetraalkylthiuram disulfides react with Cu(I) halides to give materials of composition Cu2(dtc)3X2, which are presumed to be the ionic species Cu (dtc)2 +Cu (dtc)X2 + containing Cu(II) and Cu(III), on the basis of magnetic susceptibilities, IR and ESCA spectroscopies. In the presence of triphenylphosphine, sulfur abstraction from the monosulfides leads to known monosulfide complexes of Cu(I). Some of the dithiocarbamate complexes are also accessible through degradation of alkylimonium trithiolane and tetrathiolane halocuprate(I) compounds.  相似文献   

15.
The preparation and some properties of the deprotonated complexes of oxamic acid with Au(III) and Rh(III) are reported. On the basis of analytical results, conductometric measurements, magnetic moments and spectral data (IR and UV-visible), a square planar structure is proposed for K[AuL(OH)2] and octahedral for K3[RhL 3] 3H2O (whereLH2=oxamic acid).L 2– acts as a bidentate, non-bridging ligand.
Komplexe der Oxamidsäure mit Au(III) und Rh(III)
Zusammenfassung Es wird über die Darstellung und einige Eigenschaften von deprotonierten Komplexen der Oxamidsäure mit Au(III) und Rh(III) berichtet. Auf der Grundlage von analytischen Ergebnissen, Leitfähigkeitsmessungen, magnetischen Momenten und IR- und UV(vis)-spektroskopischen Daten wird für K[AuL(OH)2] eine quadratisch planare und für K3[RhL 3] 3 H2O eine oktaedrische Struktur vorgeschlagen (LH2=Oxamidsäure).L 2– reagiert als zweizähniger, nicht überbrückender Ligand.
  相似文献   

16.
Abstract

The complexes [TlR2(Td)], [TlR2(BTd)], [HgR(Td)] and [HgR(BTd)] (R = Me, Ph; HTd = thiohydantoin; HBTd = 5-(benzylidene)-2-thiohydantoin) were prepared by reacting the appropriate ligand with the appropriate diorganothallium hydroxide or mono-organomercury acetate. They have been studied in the solid state (by vibrational spectroscopy and mass spectrometry) and in solution (by using NMR). In addition, the crystal structure of [TlMe2(BTd)] has been determined by X-ray diffraction. The crystals have a polymeric structure in which each thallium atom is coordinated to the two methyl C atoms, the S and N atoms of one BTd ligand. the S atom of another and the O atom of a third. The coordination modes of the two ligands in the other complexes are discussed on this basis in the light of spectroscopic data.  相似文献   

17.
The synthesis and characterization of heteroleptic complexes with the formulations [(η6-arene)RuCl(fcdpm)] (η6-arene = C6H6, C10H14) and [(η5-C5Me5)MCl(fcdpm)] (M = Rh, Ir; fcdpm = 5-ferrocenyldipyrromethene) have been reported. All the complexes have been characterized by elemental analyses, IR, 1H NMR and electronic spectral studies. Structures of [(η6-C6H6)RuCl(fcdpm)] and [(η6-C10H14)RuCl(fcdpm)] have been determined crystallographically. Chelating monoanionic linkage of fcdpm to the respective metal centres has been supported by spectral and structural studies. Further, reactivity of the representative complex [(η6-C10H14)RuCl(fcdpm)] with ammonium thiocyanate (NH4SCN) and triphenylphosphine (PPh3) have been examined.  相似文献   

18.
Abstract

The V(III)-pyrazine system was examined spectroscopically in the isoamyl alcohol solution. An unstable, violet-red, binuclear vanadium(III) complex [V2(pyraz)Cl4]2+ was found to be formed. On exposure to air it was slowly converted into a sparingly soluble green vanadium(IV) compound, [VO(pyraz)OH]Cl.H2O. This compound was examined by the analytical, spectroscopic (electronic and infra-red spectra) and magnetic methods.  相似文献   

19.
Abstract

The coordination properties of 5-amino-1,3,4-thiadiazole-2-sulfonamide (Hats) with Cu(II), Ni(II) and Zn(II) ions, are analyzed. Although the ligand presents several donor atoms, we have only observed three coordination behaviors: (i) as a monodentate ligand through the Nsulfonamido atom, (ii) as a bridging ligand linking the metal ions through the Nsulfonamido and Nthiadizole atoms and (iii) as a bridging ligand linking metal ions through the N and O atoms of the sulfonamidate group. It is noteworthy that coordination mode (iii) is observed for the first time in heterocyclic sulfonamides complexes. In addition, the conformation of the Hats as counter-ion is analyzed and compared with the conformations that the ligand adopts in metal complexes.  相似文献   

20.
Abstract

Anhydrous vanadium trichloride reacts with azoles in low concentrated ethyl alcohol solution of V(III) to produce 1:1 electrolytic complexes of the type [V (azole)4Cl2]+. Studies of the visible spectra of all the above complexes demonstrate that the vanadium(III) is octahedrally co-ordinated. The room temperature magnetic moments of the complexes (~ 2.8 B.M.) are consistant with the presence of two unpaired electrons per vanadium atom. At higher concn. of V(III) the polynuclear violet-red complexes probably are formed.  相似文献   

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