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1.
Five novel zinc(II) complexes of salicylaldehyde 3-hexamethyleneiminyl thiosemicarbazone were synthesized and physico-chemically characterized. The complexes were given the formulae [Zn(HL)2] (1), [Zn(L)py] (2), [Zn(L)bipy] · 3.5H2O (3), [Zn(L)phen] · H2O (4) and [Zn(L)γ-pic] (5). The thiosemicarbazone binds the metal as a dianionic ONS donor ligand in all the complexes, except in 1. Compound 1 is a homoleptic complex with zinc occupying the center of a distorted tetrahedral environment and being coordinated by two azomethine nitrogen and two thiolate sulfur atoms.  相似文献   

2.
A new semicarbazone (HL) based on di-2-pyridyl ketone and its three cadmium(II) complexes [CdL(CH3COO)]2 · 2CH3OH (1), Cd(HL)Br2 (2) and [Cd2L2N3]2 · H2O (3) were synthesized and characterized by different physicochemical techniques. The complex, [CdL(CH3COO)]2 · 2CH3OH (1) is having a dimeric structure. In complexes 1 and 3, the ligand moieties are coordinated as monoanionic (L) forms and in complex 2, the ligand is coordinated as neutral (HL) one. The coordination geometry around cadmium(II) in 1 is distorted octahedral, as obtained by X-ray diffraction studies.  相似文献   

3.
Five new transition metal complexes [MnL(OAc)]·H2O (1), [FeLCl2] (2), [NiL2]·H2O (3), [CuLCl] (4) and [ZnL2]·2H2O (5) have been synthesized using a tridentate Schiff base ligand, HL (quinoxaline-2-carboxalidine-2-amino-5-methylphenol) and the complexes have been characterized by physicochemical and spectroscopic techniques. The spectral analyses reveal an octahedral geometry for 3, square pyramidal structure for 2 and square planar structure for 4. Analytical and physicochemical data indicate tetrahedral structure for 1 and octahedral structure for 5. The crystallographic study reveals that [NiL2]·H2O shows distorted octahedral geometry with a cis arrangement of N4O2 donor set of the bis Schiff base and exhibits a two-dimensional polymeric structure parallel to [0 1 0] plane. The complexes were screened for catalytic phenol hydroxylation reaction. Coordinatively unsaturated manganese(II), iron(III) and copper(II) complexes were found to be active catalysts. The poor catalytic activity of the nickel(II) complex is due to coordinatively saturated octahedral nature of the complex. Maximum conversion of phenol was observed for the copper(II) complex and the major product was catechol.  相似文献   

4.
5.
The organotin(IV) complexes R2Sn(tpu)2 · L [L = 2MeOH, R = Me (1); L = 0: R = n-Bu (2), Ph (3), PhCH2 (4)], R3Sn(Hthpu) [R = Me (5), n-Bu (6), Ph (7), PhCH2 (8)] and (R2SnCl)2 (dtpu) · L [L = H2O, R = Me (9); L = 0: R = n-Bu (10), Ph (11), PhCH2 (12)] have been synthesized, where tpu, Hthpu and dtpu are the anions of 6-thiopurine (Htpu), 2-thio-6-hydroxypurine (H2thpu) and 2,6-dithiopurine (H2dtpu), respectively. All the complexes 1-12 have been characterized by elemental, IR, 1H, 13C and 119Sn NMR spectra analyses. And complexes 1, 2, 7 and 9 have also been determined by X-ray crystallography, complexes 1 and 2 are both six-coordinated with R2Sn coordinated to the thiol/thione S and heterocyclic N atoms but the coordination modes differed. As for complex 7 and 9, the geometries of Sn atoms are distorted trigonal bipyramidal. Moreover, the packing of complexes 1, 2, 7 and 9 are stabilized by the hydrogen bonding and weak interactions.  相似文献   

6.
Four supramolecular complexes [MnL1(H2O)2] (1), {[CoL2(OAc)(H2O)]2Co}·5CH3CH2OH (2), {[NiL3(OAc)(CH3OH)]2Ni}·2CH3COCH3·2CH3OH (3) and {[ZnL2(OAc)]2Zn}·CHCl3 (4), have been synthesized and characterized by elemental analyses, IR, UV–Vis spectra and X-ray diffraction techniques. All the complexes have the trinuclear configuration except for MnII complex being mononuclear configuration. Every trinuclear complex contains two acetate ions coordinate to the three metal ions via a familiar M–O–C–O–M (M = Co, Ni, Zn) coordinated mode. Although complexes 1 and 3 display 1D supramolecular chains, the different coordination environments (mononuclear in 1, trinuclear in 3) provoke divergence in the structures and aggregations of the chain subunits. Complex 2 forms a 3D hydrogen-bonding supramolecular networks possessing a channel composing of six O–H···O hydrogen bonds, while complex 4 exhibits a 2D hydrogen-bonding supramolecular networks with the formation of “grottos” occupied by chloroform molecules through intermolecular hydrogen-bond interactions. The spectral properties of the title complexes have been further discussed in detail.  相似文献   

7.
The reactions of palladium(II) chloride, PPh3 and heterocyclic-N/NS ligand in a mixture of CH3CN (5 ml) and CH3OH (5 ml) produced [PdCl2(PPh3)(L1)]·(CH3CN) (1) (L1 = ADMT = 3-amino-5,6-dimethyl-1,2,4-triazine), [PdCl2(PPh3)(L2)] (2) (L2 = 3-CNpy = 3-cyanopyridine), [PdCl(PPh3)(L3)]2·(CH3CN) (3), [PdCl(PPh3)2(HL3)]Cl (4) (HL3 = Hmbt = 2-mercaptobenzothiazole). The coordination geometry around the Pd atoms in these complexes is a distorted square plane. In 3, L3 acts as a bidentate ligand, bridging two metal centers, while in 4, HL3 appears as monodentate ligand with one nitrogen donor atom uncoordinated. Complexes 1-4 are characterized by IR, luminescence, NMR and single crystal X-ray diffraction analysis. All complexes exhibit luminescence in solid state at room temperature.  相似文献   

8.
Four new solvent-induced Cu(II) complexes with the chemical formulae [{Cu(HL)(CH3OH)}2Cu] · CH3OH (1), [{(Cu(HL))2(CH3CH2OH)2}Cu] (2), [{CuL(H2O)}2Cu2] · 2CH3CH2CH2OH (3) and [{(Cu(HL))2(CH3CH2CH2CH2OH)2}Cu] (4), where H4L = 6,6′-dihydroxy-2,2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenol, have been synthesized and characterized by elemental analyses, 1H NMR, FT-IR, UV–Vis spectra, TG-DTA, molar conductances and X-ray crystallography. Complexes 1, 2 and 4 have an elongated square-pyramidal geometry with an unusually long bond from the penta-coordinated Cu(II) centres to the oxygen atoms of the apically coordinated solvent (methanol, ethanol or n-butanol) molecules for the terminal Cu(II) ions, and a square planar geometry distorted tetrahedrally for the central Cu(II) ion. In complex 3, the terminal Cu(II) ions have trigonal bipyramidal coordination geometries constituted by equatorial O2N donor sites, with one oxygen atom from one of the coordinated water molecules and one nitrogen atom from a completely deprotonated L4− ligand unit in the axial positions, and the central Cu(II) ions are in slightly tetrahedrally distorted square planar geometries constituted by four phenoxo oxygen donors from two completely deprotonated L4− ligand units, and these form a tetrametal Cu–O–Cu–O–Cu–O–Cu–O eight-membered ring. These four complexes exhibit strong hydrogen bonding interactions in the solid state. Moreover, co-crystallizing n-propanol molecules link two other adjacent complex molecules into a self-assembled infinite 2D supramolecular structure via the intermolecular hydrogen bonds in complex 3.  相似文献   

9.
Five new Cu(II) complexes [Cu(psa)(phen)] · 3H2O (1), [Cu(psa)(2bpy)] · 0.5H2O (2), [Cu(psa)(2bpy)(H2O)] · 3H2O (3), [Cu(psa)(4bpy)] · H2O (4), and [Cu(psa)0.5(N3)(2bpy)] (5) (H2psa = phenylsuccinic acid, phen = 1,10-phenanthroline, 2bpy = 2,2′-bipyridine, and 4bpy = 4,4′-bipyridine) were obtained under solvothermal conditions and characterized by single-crystal X-ray diffraction. Complexes 2 and 3 were formed by one-pot reaction. In complex 2, Cu(II) ion is four-coordinated and locates at a slightly distorted square center. In complex 3, the coordinated water molecule occupies the axial site of Cu(II) ion forming a tetragonal pyramid geometry. Complexes 1 and 3 are of 1D chain structures, and extended into 2D supramolecular network by hydrogen bonds. Complex 2 is of zipper structure, and further assembled into 2D supramolecular network by hydrogen bonds and π–π stacking interactions. Complex 4 is a 3D CdSO4-like structure with twofold interpenetration, while complex 5 is a dinuclear compound. The different structures of complexes 15 can be attributed to using the auxiliary ligands, indicating an important role of the auxiliary ligands in assembly and structure of the title complexes.  相似文献   

10.
The synthesis of lanthanide hydroxo complexes stabilized by a carbon-bridged bis(phenolate) ligand 2,2’-methylene-bis(6-tert-butyl-4-methylphenoxo) (MBMP2−) was described, and their reactivity toward phenyl isocyanate was explored. Reactions of (MBMP)Ln(C5H5)(THF)2 with a molar equiv. of water in THF at −78 °C afforded the bis(phenolate) lanthanide hydroxides as dimers [{(MBMP)Ln(μ-OH)(THF)2}2] [Ln = Nd (1), Yb (2)] in high yields. Complexes 1 and 2 reacted with phenyl isocyanate in THF, after workup, to give the desired O−H addition products, [(MBMP)Ln(μ-η12-O2CNHPh)(THF)2]2 [Ln = Nd (3), Yb (4)] in excellent isolated yields. These complexes were well characterized, and the molecular structures of complexes 2 to 4 were determined by X-ray crystallography. The ytterbium atom in complex 2 is coordinated to six oxygen atoms to form a distorted octahedral geometry, whereas each metal center in complexes 3 and 4 is seven-coordinated, and the coordination geometry can be best described as a distorted pentagonal bipyramid.  相似文献   

11.
The coordination behaviour of a series of pyridyl azamacrocyclic ligands, some of them containing cyanomethyl and cyanoethyl pendant-arms, towards Mn(II) ion was studied. All the complexes were characterized by microanalysis, LSI mass spectrometry, IR, UV-Vis spectroscopy and magnetic measurements. Crystal structures of [MnL1][MnBr4] (1), [MnL3][MnBr4] · 2CH3CN (3), [Mn2L5Br4] · 2CH3CN (5) and [Mn2L6Br4] (6) complexes have been determined. The X-ray studies show the presence of an ionic mixed octahedral-tetrahedral complex for 1 and 2, with the manganese ion of the cation complex, endomacrocyclicly coordinated by the six nitrogen donor atoms from the macrocyclic backbone in a distorted octahedral geometry. Instead, the complexes 5 and 6 are dinuclear, and both manganese ions are coordinated by one pyridinic and two amine nitrogen atoms from the macrocyclic backbone and two bromide ions, being the geometry around the metal better described as distorted square pyramidal. In all cases, the nitrile pendant-arms do not show coordination to the metal ion.  相似文献   

12.
The preparation of the N-heterocyclic carbene coordinated gallium complexes [GaH3(IXy)] (1), [GaH3(IDipp)] (2), [GaClH2(IMes)] (3) and [GaCl2H(IMes)] (4), where IXy = 1,3-bis(2,6-dimethylphenyl)imidazol-2-ylidene, IDipp = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene and IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene, are reported. All four complexes have been characterised by 1H, 13C NMR and IR spectroscopy and, for complexes 2, 3 and 4, single crystal X-ray structure determination. These compounds represent some of the most thermally stable molecular gallium hydrides known, with 4 being the most thermally stable gallium hydride reported (dec. 274 °C). These remarkable thermal stabilities translate to significant aerobic stability such that all four compounds may be handled in dry air without significant decomposition. Compounds 2, 3 and 4 exist as distorted tetrahedra in the solid state with gallium to carbene C-donor bonds that shorten with increasing Lewis acidity of the gallium centre. Compound 2 co-crystallizes with 1 equiv. of 2,6-diisopropylphenylaniline and exhibits several weak intermolecular bonding interactions in the solid-state.  相似文献   

13.
Treatments of nitrogen-containing heterocyclic dithioether ligands, 1,2-bis(4-(pyridin-3-yl) pyrimidin-2-ylthio) ethane (L1) and 1,3-bis (4-(pyridin-3-yl) pyrimidin-2-ylthio) propane (L2), with zinc or cadmium salts have resulted in the interesting frameworks with structural motifs from a mononuclear macrocycle or a dinuclear macrocycle to an one-dimensional structure. A small difference of the alkyl length between L1 and L2 led to conspicuous changes of the fluorescent properties of both ligands and their complexes. Mainly due to the size of metal atoms, structures of [ZnL2I2] (1) and [CdL2I2] (2) are varied from a mononuclear macrocycle to a 1D framework, while {[ZnL2(H2O)4](ClO4)2}2 (3) and {[CdL2(H2O)4](ClO4)2}2 (4) are dinuclear macrocycles in which perchlorate anions may play an important template role. As for complexes 58 ([ZnL1I2]n (5), [CdL1I2]n (6), {{[ZnL12(H2O)4](ClO4)2}0.5 · L10.5 · CH3OH} (7), {{[Cd0.5L1(H2O)2](ClO4)}2 · CH3OH · L1} (8)), the self-assemble processes were mainly directed by the organic ligand in the reactions of L1 with metal salts. Complexes 14 exhibit blue fluorescence emissions, among which 1 and 2 may be suitable as candidates for blue fluorescent materials.  相似文献   

14.
The ortho-metallated complexes [Pd22(C,C)-C6H4(PPh2CHC(O)C6H5R}2(μ-Cl)2] (R = Ph (1a), NO2 (1b), Br (1c)) were prepared by refluxing equimolar mixtures of Ph3PCHC(O)C6H5R, (R = Ph, NO2, Br) and Pd(OAc)2 in MeOH, followed by an excess of NaCl. The dinuclear complexes (1a-1c) react with silver trifluoromethylsulfonate and bidentate ligands [L = bipy (2,2′-bipyridine), phen (phenanthroline), dppe (bis(diphenylphosphino)ethane), dppp (bis(diphenylphosphino)propane)] giving the mononuclear stabilized orthopalladated complexes in endo position [Pd{κ2(C,C)-C6H4(PPh2CHC(O)R}L](OTf) [R = Ph, L = phen (2a), bipy (3a), dppe (4a), dppp (5a); R = NO2, L = phen (2b), bipy (3b), dppe (4b), dppp (5b); R = Br, L = phen (2c), bipy (3c), dppe (4c), dppp (5c); OTf = trifluoromethylsulfonate anion]. Orthometalation and ylidic C-coordination are demonstrated by an X-ray diffraction study of 2c and 3c. In the structures, the palladium atom shows a slightly distorted square-planar coordination geometry.  相似文献   

15.
Novel rhenium complexes containing the maltolate (mal) or kojate (koj) anions as chelating ligands have been synthesized: [ReOCl(mal)2] (1), [ReOCl2(mal)(PPh3)] (2), [ReOBr2(mal)(PPh3)] (3), [ReOCl2(koj)(PPh3)] (4) and [ReOBr2(koj)(PPh3)] (5). The products have been characterized by FTIR, 1H, 13C, and 31P NMR spectroscopies and elemental analysis. The crystal and molecular structures of all complexes were determined. Complex 1 crystallizes monoclinic, space group C2/c, Z = 8. It contains two O,O′-bidentate maltolate ligands and one chloro ligand at the (ReO)3+ unit, so that a distorted octahedral geometry is adopted by the six-coordinated rhenium(V) center. The chloro ligand occupies a cis position to the oxo ligand. Complexes 2 and 3 are isostructural and crystallize orthorhombic, space group Pbca and Z = 8. The isostructural complexes 4 and 5 crystallize monoclinic, space group P21/n and Z = 4. In complexes 25, the (ReO)3+ unit is coordinated by a monoanionic O,O-bidentate unit of the maltolate (2 and 3) or kojate (4 and 5) ligand, one triphenylphosphine and two halogeno ligands (Cl in 2 and 4; Br in 3 and 5), with the rhenium(V) center in a distorted octahedral environment. The halide ligands are in cis positions to each other.  相似文献   

16.
The crystal structures of compounds Na[Cr(dipic)2] · 2H2O (1) and [Cr(dipic)(phen)Cl] · 1/2H2O (2), dipic = dipicolinate, phen = 1,10-phenantroline, were determined. In both complexes, Cr(III) is in a distorted octahedral environment. In complex (1), the metal is coordinated to two nearly perpendicular dipic anions acting as tridentate ligands through one oxygen of each carboxylate group and the pyridinic nitrogen atom. In complex (2), Cr(III) ion is similarly coordinated to a dipic anion, defining a ligand equatorial plane. The phen molecule bridges the remaining equatorial coordination site and one of the axial positions through its N-atoms. The other axial position is occupied by a chloride ion.  相似文献   

17.
18.
Five new mixed ligand coper(II) complexes, viz. [Cu(SAA)(H2O)] (1), [Cu(SAA)(MeImH)] (2), [Cu(SAA)(EtImH)] (3), [Cu(SAA)(BenzImH)] (4) and [Cu(SAA)(MebenzImH)] (5), where SAA = salicylideneanthranilic acid, MeImH = 2-methylimidazole, EtImH = 2-ethylimidazole, BenzImH = benzimidazole, MebenzImH = 2-methylbenzimidazole, have been synthesized and characterized by means of elemental analysis, FAB mass spectrometry, magnetic susceptibility, X-band EPR, electronic spectroscopy, IR and cyclic voltammetry. The frozen solution EPR spectra of the complexes have shown axial features. Single crystal X-ray analysis of 2 and 3 has revealed the presence of a distorted square planar geometry (N2O2) in the complexes. The superoxide dismutase (SOD) activity of the present complexes has also been measured and discussed.  相似文献   

19.
The coordination geometry and supramolecular structures of three copper(II) complexes of two α-hydroxycarboxylates and one α-methoxycarboxylate with nitrogen donor co-ligands are discussed. The complexes have been characterized by elemental analysis, ESI-MS, IR and electronic spectroscopy, thermogravimetric analysis and magnetic measurements. The X-ray structure analysis of all the complexes, namely [(BPCA)CuII(MA)] (1), [(BPCA)CuII(MPA)(H2O)] (2) and [(BPCA)CuII(BA)]n (3), where BPCA = bis(2-pyridylcarbonyl)amidate, MA = racemic mandelate, MPA = racemic α-methoxy phenylacetate and BA = benzilate anion, shows the copper(II) ion in a distorted square-pyramidal geometry. In 1 the mandelate anion is coordinated to the copper(II) center in a bidentate fashion while in 2 the α-methoxycarboxylate is monodentate. In both cases a one-dimensional supramolecular array is formed through hydrogen bonds: the mononuclear units are directly connected in 1 by the MA hydroxyl group, whereas in 2 is the coordinated water that operates as H donor towards the MPA carboxylate group and the BPCA carbonyl oxygens of nearby complexes. In 3 the benzilate anion, acting as bridging ligand between copper ions, gives rise to a one-dimensional coordination polymer. In the latter, intra- and inter-chain π?π stacking interactions between pyridines and one phenyl ring of benzilate anions are observed in the packing.  相似文献   

20.
A polydentate ligand, H2L “[1-(5-isopropyl-2-methyl phenoxy)-3-(N-2-hydroxy benzyl-N-((pyridine-2-yl)amino) propan-2-ol]”, containing a N2O2 donor moiety was synthesized by refluxing 2-((5-isopropyl-2-methylphenoxy)methyl)oxirane and HBPA (N-(2-hydroxybenzyl)-N-(2-pyridylmethyl)amine). This synthesized ligand was used for the preparation of complexes with different metal ions, viz. [Cu(HL)Cl] (1), [Ni(HL)Cl] (2), [Zn(HL)Cl] (3) and [Fe(HL)Cl2] (4). The ligand and metal complexes were characterized by 1H NMR, mass, ESI-MS, elemental analysis, IR, UV-Vis and electron paramagnetic resonance (EPR) spectroscopy. The crystal structure for one of the complexes, [Cu(HL)Cl], was solved from the X-ray crystallography data. The structure of the complex, based on the trigonality index tau, suggests an intermediate geometry between square pyramidal (sp) and trigonal bipyramidal (tb). Both the ligand and the metal complexes show oxidative cleavage of plasmid DNA (pBR322) without addition of any exogenous agent, even at a concentration of 5 μM. The binding constants for these compounds were found to be in the range 5.33-0.065 × 105 M−1.  相似文献   

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