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961.
《Journal of Coordination Chemistry》2012,65(2):289-297
Abstract CuL 5H2O (H2L = 1, 15-diaza-3, 4; 12, 13-dibenzo-5, 8, 11 -trioxacyclo-octadecane-N,N′-diacetic acid) crystallized from water. Its crystal structure was determined by X-ray diffraction analysis and refined in space group Pnma, a = 20.1784(11), b = 15.8745(9), c = 8.9266(5)Å, V = 2859.4(3)Å3, Z = 4, ?(MOKα) = 0.71073, RW . = 0.0294 for 1822 observed reflection [I > 2[sgrave](I)]. The copper atom is surrounded by two nitrogen atoms, two oxygen atoms from the carboxyl groups in the ligand and one oxygen atom from a coordinated water to form a distorted square pyramidal arrangement. The three ether oxygen atoms in the cycle have no contact with the copper ion. The stability constant for the 1 :1 complex of copper(II) and protonation constants for the ligand have been determined by potentiometric titration in water (I = 0.1, KNO3) at 25°C. Electronic spectra, conductivity measurements, thermal analysis, and the EPR of the complex are discussed in terms of the crystal structure. 相似文献
962.
《Journal of Coordination Chemistry》2012,65(7):1224-1237
Two new cobalt(II) complexes, [Co(L3)2]·CH3OH·CH3COCH3 (1) (HL3 = 1-(2-{[(E)-3,5-dichloro-2-hydroxybenzylidene]amino}phenyl)ethanone oxime) and Co(L4)2 (2) (HL4 = 1-(2-{[(E)-3,5-dibromo-2-hydroxybenzylidene]amino}phenyl)ethanone oxime), have been synthesized via complexation of Co(II) acetate tetrahydrate with HL1 and HL2. HL1, HL2, and their corresponding Co(II) complexes were characterized by IR, 1H NMR spectra, as well as by elemental analysis and UV–Vis spectroscopy, respectively. The crystal structures of the complexes have been determined by single-crystal X-ray diffraction. 1 and 2 display that extensive hydrogen bonds and C–X···π bonding interactions construct the 1-D infinite chain [Co(L3)2]·CH3OH·CH3COCH3 and Co(L4)2 into 2-D supramolecular frameworks. The electrochemical properties of two Co(II) complexes were also investigated by cyclic voltammetry. 相似文献
963.
《Journal of Coordination Chemistry》2012,65(24):4009-4017
Microwave chemistry is a green chemical method that improves reaction conditions and product yields while reducing solvent amounts and reaction times. The main aim of this article is to synthesize the tetradentate N2O2 ligand [HO(Ar)CH=N–(CH2)2–N=CH(Ar)OH] and manganese(II), cobalt(II), nickel(II), and zinc(II) complexes of the type ML by classical and microwave techniques. The resulting Schiff base and its complexes are characterized by 1H NMR, infrared, elemental analysis, and electronic spectral data. The ligand and its Co(II) and Mn(II) complexes were further identified by X-ray diffraction and mass spectra to confirm the structure. The results suggest that the metal is bonded to the ligand through the phenolic oxygen and the imino nitrogen. 相似文献
964.
《Journal of Coordination Chemistry》2012,65(9):1015-1024
Mercury(II) and lead(II) complexes with 2,2′-bis(4,5-dimethylimidazole) (DmImH), [Hg(DmImH)(SCN)2] and [Pb(DmImH)(NCS)2], have been synthesized and characterized by IR specta and elemental analyses. The molecular structure of [Pb(DmImH)(NCS)2] n is polymeric with four-coordinate lead atoms. The [Hg(DmImH)(SCN)2] complex is built up of monomeric Hg(SCN)2 units with one “DmImH” ligand coordinated to the Hg atom via the two N atoms in a distorted tetrahedral environment. The thiocyanate ligands are coordinated to lead via nitrogen, but to mercury via the sulfur. There are π–π stacking interactions between the parallel aromatic rings in the mercury(II) complex. 相似文献
965.
《Journal of Coordination Chemistry》2012,65(11):2004-2011
The reaction of Cu(Ac)2·4H2O with 2-[(3,5-dichloro-2-hydroxy-benzylidene)-amino]-2hydroxymethyl-propane-1,3-diol (H4L) and 4,4′-bipyridyl-N,N′-dioxide (4,4′-bipy-NO) in DMF under solvothermal conditions leads to the formation of a di-radical dinuclear copper complex [Cu2(4,4′-bipy-NO)(dcdmap)4] (1) (dcdmap is the anion of 2,4-dichloro-6dimethylaminomethyl-phenol, synthesized by an in situ reaction). Compound 1 was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. Complex 1 displays dominant anti-ferromagnetic interaction between oxyradicals and copper ion and oxyradical. 相似文献
966.
《Journal of Coordination Chemistry》2012,65(24):4345-4354
Reactions of 1,2-di(o-aminophenylthio)ethane with 3-ethoxy-2-hydroxybenzaldehyde yield the new hexadentate N2S2O2 donor thioether Schiff base 1,2-bis(2-((2-(thio)phenylimino)methyl)-6-ethoxyphenol)ethane (H2L). Ni(II), Zn(II), Cd(II), and Hg(II) complexes of this ligand were prepared. Of these complexes, [NiL]·2H2O has been structurally characterized by X-ray crystallography. The coordination geometry around Ni(II) was described as octahedral. Zn(II), Cd(II), and Hg(II) complexes and the Schiff base ligand have been characterized by CHN analyses, molar conductivity, UV–vis, FT-IR, 1H, and 13C NMR spectroscopy. 相似文献
967.
968.
《Journal of Coordination Chemistry》2012,65(4):651-662
Mixed ligand complexes of the type MLL′Cl2 (where M?=?Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II), L?=?ligand derived from the reaction between benzofuran-2-carbohydrazide and 3,4,5-trimethoxybenzaldehyde (TMeOBFC), and L′?=?ortho-phenylenediamine (opd)/2,6-diaminopyridine (2,6-dap)) have been synthesized. The complexes have been characterized by analytical data, IR, UV-Vis, 1H NMR, DART-MS and ESR spectral data, and magnetic studies. Molar conductance values indicate that the complexes are non-electrolytic in DMF. Antibacterial and antifungal activities of the ligands and complexes have been screened against bacteria Escherichia coli and Staphylococcus aureus and against fungi Aspergillus niger and Aspergillus flavus. 相似文献
969.
《Journal of Coordination Chemistry》2012,65(5):819-827
A series of anionic five-coordinate binary oxorhenium(V) complexes with dithiolato ligands, Bu4N[ReO(L1)2] (1a), Bu4N[ReO(L2)2] (1b), and Bu4N[ReO(L3)2] (1c), and a series of neutral octahedral ternary oxorhenium(V) complexes of mixed dithiolato and bipyridine ligands, [ReO(L1)(bpy)Cl] (2a), [ReO(L2)(bpy)Cl] (2b), and [ReO(L3)(bpy)Cl] (2c) (where L1H2 = ethane-1,2-dithiol, L2H2 = propane-1,3-dithiol, L3H2 = toluene-3,4-dithiol, and bpy = 2,2′-bipyridine), were isolated and characterized by physicochemical and spectroscopic methods. The solid state structure of 1c was established by X-ray crystallography. All the mononuclear oxorhenium(V) complexes are diamagnetic. The redox behavior of all the complexes has been studied voltammetrically. 相似文献
970.
《Journal of Coordination Chemistry》2012,65(12):1345-1353
A binuclear complex {[Mn(bpy)2(CuL)(H2O)2](ClO4)2} (2) and its CuL (1) precursor (H2L?=?2,3-dioxo-5,6?:?14,15-dichlorobenzo-7,13-diphenyl-1,4,8,12-tetraazacyclo-pentadeca-7,12-diene; bpy?=?2,2′-dipyridyl) have been synthesized and characterized structurally. Complex 1 consists of the neutral [CuL] fragments and methanol molecules. In complex 2, [Mn(bpy)2(CuL)]2+ cation, two water molecules and two perchloric anions make up of the crystal. Mn(II) is coordinated by four nitrogen atoms from two 2,2′-dipyridyl and two oxygen atoms from the Cu(II) precursor. Magnetic characterization of 2 exhibits an antiferromagnetic interaction between Cu(II) and Mn(II) ions, with J?=??74.1?cm?1. 相似文献