Synthesis and crystal structure of a new copper(II) binuclear complex bridged by the reduced derivative of a nitronyl nitroxide biradical

A new copper(II) binuclear complex, [Cu(hfac)₂]₂(IMH)₂Ph(OMe)₂ ((IMH)₂Ph(OMe)₂?=?2,5-dimethoxyl-1,4-bis(4′,4′,5′,5′-tetramethylimidazoline-3′-oxide)benzene, hfac?=?hexafluoroacetonate), bridged by a reduced derivative of a nitronyl nitroxide biradical has been synthesized and characterized by X-ray crystallography. The complex crystallizes in the monoclinic space group P2₁/n, with a?=?10.002(14), b?=?19.950(3), c?= 14.504(2) Å, β?=?108.842(3)° and Z?=?2. The structure refined to a final R value of 0.0644. The complex contains two copper(II) ions bridged by a reduced derivative of a nitronyl nitroxide biradical with a Cu?···?Cu separation of 8.430(2) Å.     

Self-assembly and crystal structure of a three-dimensional copper(II) complex

A copper(II) complex of a sulfonate derivative of chrysin, 5,7-bihydroxyflavone-6-sulfonate, Cu(C₁₅H₈O₇S)(3H₂O), has been prepared. The complex was characterized by elemental analysis, spectroscopic measurements and single-crystal X-ray diffraction studies. It crystallizes in the monoclinic space group C2/c, with a?=?16.036(18), b?=?6.944(8), c?=?28.03(3)?Å, β?=?94.463(17)°, V?=?3112(6)?ų, Z?=?8. In the complex, Cu(II) is five-coordinate and all donors are oxygen atoms. Hydrogen bonds and π–π stacking interactions in the crystal lead to the formation of a three-dimensional supramolecular motif.     

The structure of di-μ-chloro- bis - {chloro( N,N -diethylethane-1,2-diamine-κ 2)copper(II)}

Dichloro(N,N-diethyl-ethane-1,2-diamine)copper(II) has copper(II) ions in square pyramidal coordination. The two nitrogen atoms of the diamine {Cu–N_primary?=?1.979(3), Cu–N_tertiary?=?2.108(2)?Å} and two chloride ions are in the basal plane {Cu–Cl1?=?2.2680(9), Cu–Cl2?=?2.2989(8)?Å}. A centrosymmetrical dimer di-μ-chloro-bis{chloro(N,N-diethylethane-1,2-diamine-κ²)copper(II)}, C₆H1₆Cl₂CuN₂, is formed by axial coordination by Cl2, trans to the tertiary nitrogen, to a second copper(II) ion, with Cu?···?Cuⁱ?=?3.4855(9) and Cl2–Cuⁱ?=?2.7860(8)?Å. The dimer is also linked by H-bond N1–H?···?Cl1ⁱ.     

Synthesis,structure and antimicrobial study of two new copper(II) complexes derived from N-(3-aminopropyl) benzylamine ligand (apba) and N-salicylidene-apba

Two new copper(II) complexes were synthesized by reaction of N-(3-aminopropyl)benzylamine (L1: apba, for complex 1) and N-salicylidene-apba (L2: for complex 2) with Cu²⁺. Crystals of complex 1 were orthorhombic, space group pccn, with a?=?15.2149(10), b?=?25.0071(16), c?=?7.6280(5)?Å and α?=?β?=?γ?=?90°. Complex 2 crystals were monoclinic, space group P2₁/c, with a?=?8.688(6), b?=?12.812(9), c?=?16.022(11)?Å and β?=?99.241(10)°. Structures of the two complexes were centro-symmetric and both Cu(II) atoms were four coordinate with a distorted square-planar geometry. The toxicity of the complexes was evaluated by testing antimicrobial activity against bacterial strands.     

A linear trinuclear complex of copper(II) with N,N′-bis(2-hydroxy-5-methoxybenzelidene)-1,3-diiminopropane

The synthesis and X-ray crystal structure of a linear phenolate-bridged Cu(II) complex 1 with a Cu–Cu bond distance of 2.9260(5)?Å is reported. The complex consists of three Cu(II) ions with two molecules of the N,N′-bis(2-hydroxy-5-methoxybenzelidene)-l,3-diiminopropane ligand and two nitrate ions in such a manner that one ligand is connected with two Cu(II) ions. The complex is monoclinic, space group P2₁/n, with a?=?10.6305(5), b?=?13.0719(7), c?=?14.6336(8)?Å and β?=?102.549(1)° at 293?K, Z?=?2. The structure shows deprotonation of the phenolate oxygen to form a μ₂ bridge. The magnetic moment (1.627 BM per Cu₃ unit) at 300?K reveals that the spin doublet state is the ground state.     

Synthesis,molecular structure,DNA binding and cleavage properties of a novel ternary Cu(II) complex containing dipyrido[3,2-a : 2′3′-c]phenazine and L-tryptophanate

A ternary Cu(II) complex with dipyrido[3,2-a?:?2′3′-c]phenazine(dppz) and L-tryptophanate (L-trp) has been synthesized and investigated by elemental analysis, molar conductivity, IR and X-ray diffraction. The complex crystallizes in the monoclimic space group P2₁ with two molecules in a unit cell of dimensions, a?=?7.949(2)?Å, b?=?10.724(3)?Å, c?=?18.580(5)?Å, β?=?93.697(5)°, V?=?1580.7(8)?ų, R ₁?=?0.0310, and wR ₂?=?0.0382. The central copper(II) ion has a distorted square-pyramidal geometry, in which the N,O-donor tryptophanate and N,N-donor heterocyclic base dppz are in the basal plane and a water molecule is coordinated at the axial site. DNA binding properties of the complex were studied by electronic absorption spectroscopy, fluorescence spectroscopy, and viscosity measurement. The DNA cleavage of the complex was investigated by agarose gel electrophoresis. The results show that the complex can bind DNA by intercalation and cleave pBR322 DNA in the presence of ascorbate.     

Synthesis and crystal structure of a copper(II) complex of the tridentate ligand di-(2-benzimidazolylmethyl)imine

A copper complex [Cu(IDB)Cl] · 0.5[CuCl₄]?·?H₂O (1) (IDB?=?di(2-benzimidazolylmethyl)imine) was synthesized and its structure was determined by X-ray single crystal diffraction. In this complex, the central copper(II) ion is four-coordinate, IDB serves as a neutral tridentate chelating ligand for the tetragonal copper ion. The cyclic voltammogram of complex 1 in CH₃CN gave two reversible redox waves (E _1/2,1?=??0.14?V and E _1/2,2?=?0.08?V versus SCE) which correspond to the Cu(II,?II)/Cu(I,?II) and Cu(II,?II)/Cu(II,?I) redox processes, respectively.     

Synthesis,crystal structure and antimicrobial properties of a copper(II) complex of an unsymmetrical tripodal ligand

A new copper(II) complex of an unsymmetrical tripodal ligand (NN₂O222) derived from tris(2-aminoethylamine)amine (tren) by substitution of one aminoethyl group by an hydroxyethyl group has been synthesized and characterized by X-ray crystallographic methods as [(NN₂O222)Cu(ImH)](ClO₄)₂·0.5H₂O (NN₂O222?=?2-[bis(2-aminoethyl)amino]ethanol; ImH?=?imidazole). Crystals of the complex are orthorhombic, space group Pna2₁, with a?=?29.983(10), b?=?15.568(5), c?=?8.127(3)?Å. Two similar monometallic cations exist in the asymmetric unit and in each case the Cu(II) ion is five-coordinate with tetragonally distorted trigonal bipyramidal geometry. Variable-temperature magnetic measurements show that there is very weak antiferromagnetic interaction between the metal ions. Cyclic voltammetry indicates quasi-reversible Cu^II/Cu^I redox behavior at +44?mV vs SCE. An antimicrobial activity study found that the complex is active against Candida albican, Staphylococcus aureus, Bacillus pumilus, Klebosiella pneumoniae and Escherichia coli, but to no greater extent than Cu(ClO₄)₂·6H₂O.     

Synthesis,DFT analysis and DNA studies,cytotoxicity and luminescence properties of a dinuclear copper(II) complex with 1,10-phenanthroline and 4-aminobenzoate

The dinuclear copper(II) complex, [Cu₂(phen)₂(4-aminobenzoate)₂(H₂O)₂](NO₃)₂·2(4-aminobenzoic acid)·3H₂O (phen = 1,10-phenanthroline), has been synthesized and structurally characterized by elemental analyses, IR, EPR, UV-visible and single-crystal X-ray crystallography. The complex crystallized in a monoclinic system with space group C2/c, a?=?26.0022(10) Å, b?=?10.2524(4) Å, c?=?20.9983(7) Å, α?=?90°, β?=?106.9550(10)° and γ?=?90°. The Cu(II) ion adopts a distorted square-pyramidal geometry formed by two N atoms from the phen ligand and two O atoms of the two 4-aminobenzoic acid ligands and one water O atom. The Cu…Cu separation is 3.0570(5) Å. A twofold axis passes through the midpoint of the Cu-Cu vector. The complex has intraligand (π–π*) fluorescence properties. The binding of this dinuclear copper(II) complex with calf thymus DNA (CT-DNA) was investigated by UV-vis absorption, fluorescence spectroscopic, cyclic voltammetric and viscosity techniques. Also, the cleavage of pBR322 DNA with dinuclear copper(II) complex was studied using gel electrophoresis method. The exhibited potent cytotoxic effects against human cell line (HepG2) and it was found to have good antimicrobial activities. The primary coordination sphere of dinuclear copper(II) complex is optimized, structural parameters are calculated and energy gaps of frontier orbital (HOMO-LUMO) have been calculated with B3LYP/6-31G/LANL2DZ level of theory in the gaseous phase. The calculated geometric and spectral results reproduced the experimental data with well agreement. Theoretical calculated molecular orbitals (HOMO-LUMO) and their energies have been calculated that suggest charge transfer occurs within the complex.     

Spectrothermal properties and crystal structure of a polynuclear µ-squarato(O1,O3)bis(monoethanolamine)copper(II) complex, [Cu(µ-sq)(mea)2] n

Catena-poly-trans-µ-(squarato-O¹,O³)bis(monoethanolamine)copper(II), [Cu(µ-C₄O₄)(C₂H₇NO)₂] _n has been prepared and characterized by elemental analysis, IR, UV-Vis, EPR, thermal analysis and single crystal X-ray diffraction. The compound crystallizes in the triclinic system, space group P-1, with a?=?5.1435(7), b?=?7.2931(10), c?=?7.5198(11)?Å, α?=105.940(11)°, β?=?98.731(11)°, γ?=?101.981(11)° and Z?=?1. The structure contains chains of squarato-O¹,O³-bridged polynuclear copper(II) units. The configuration around each copper is distorted octahedral with two nitrogen and two oxygen atoms of two bidentate neutral monoethanolamine (N,?O) ligands and two oxygen atoms of two squarato (μ-O¹,O³) ligands. These chains are held together by an extensive three-dimensional network of N-H?···?O type intermolecular hydrogen bonds and van der Waals forces. The IR, UV-Vis and EPR spectra, magnetic study and thermal analysis of the complex are described.     

Hydrothermal synthesis,structures and characterization of two new copper(II) triphosphonate compounds

Two copper(II) triphosphonate compounds, Cu[(APTPH₄)(phen)(H₂O)]?·?2.16H₂O (1) and [Cu(APTPH₄)(2,2′-bipy)(H₂O)]?·?2.63H₂O (2), have been prepared by a low temperature hydrothermal reaction from 1-aminopropane-1,1,3-triphosphonic acid (APTPH₆), CuO and a second ligand, phen?=?1,10-phenanthroline, or 2,2′-bipy?=?2,2′-bipyridyl. These two compounds were characterized by single crystal X-ray diffraction, elemental analysis, IR and TG. Crystal data for 1: Monoclinic, space group P2₁ /c, a?=?14.4830(7)?Å, b?=?9.1721(5)?Å, c?=?16.7403(8)?Å, β?=?90.101(2)°. For compound 2: Triclinic, space group P 1, a?=?7.1215(7)?Å, b?=?10.460(2)?Å, c?=?14.671(2)?Å, α?=?82.983(2)°, β?=?83.882(2)°, γ?=?80.617(2)°. In both compounds, each Cu²⁺ ion is five-coordinate with two oxygen atoms from the triphosphonate, two nitrogen atoms from the second ligand and one water molecule, to form a distorted square-pyramidal geometry. Both complexes have 3D supramolecular structures constructed by hydrogen bonds and π–π stacking interactions.     

Synthesis and crystal structure of a Cu(II) complex with mixed malonate/1,10-phenanthroline ligands

A Cu(II) complex with mixed ligands, [Cu₃(mal)₃(phen)₃(H₂O)₂]?·?11H₂O (mal?=?malonate, phen?=?1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR, UV, electron paramagnetic resonance (EPR) and luminescence spectra and single-crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group Cc with a?=?13.1631(10)?Å, b?=?20.1089(10)?Å, c?=?20.1267(13)?Å, β?=?103.500(3)°, V?=?5180.2(6)?ų, Z?=?4, and R ₁?=?0.0476 for 7993 observed reflections. In the complex, one Cu is coordinated by a mal dianion and a phen molecule, exhibiting N₂O₂ square-planar geometry, while the other two Cu atoms are coordinated, respectively, by a mal dianion, a phen and water molecules, exhibiting N₂O₃ square pyramidal coordination geometry.     

Crystal structure and spectroscopic properties of a new syn-anti carboxylate-bridged polymeric chain copper(II)–glycylglycine complex

A new polymer complex of copper(II)–glycylglycine?{[Cu(glygly)(H₂O)][Cu(glygly)(H₂O)₂]} _n ·5nH₂O (1) is reported. It crystallizes in the P2₁/c space group, with a?=?14.669(2), b?=?9.8480(10), c?=?14.053(2)?Å,?β?=?102.730(10)°?and Z?=?4. Compound 1 consists of [Cu(glygly)(H₂O)] _n 1D carboxylate-bridged polymeric chains, monomer Cu(glygly)(H₂O)₂ molecules which form hydrogen-bonded chains and uncoordinated water molecules. In all cases, the geometry around copper(II) is a slightly distorted square pyramid with the water oxygen at the apex of the pyramid. The ESR, UV-Vis and IR spectroscopy of the compound were also studied.     

Synthesis,crystal structure,spectroscopy, and nuclease activity of copper(II) complexes containing N,N-bis(2-pyridylmethyl)amine ligand

[Cu(bpea)Cl]ClO₄ (1) and a new copper(II) complex [Cu(bpma)(Ph-COO)(H₂O)]ClO₄ (2) [bpea?=?N,N-bis(2-pyridylmethyl)ethylamine; bpma?=?N,N-bis(2-pyridylmethyl)methylamine] have been synthesized. Complex 2 was crystallized in monoclinic space group P2₁/c with unit cell parameters a ?=?16.460(6)?Å, b ?=?11.222(4)?Å, c?=?12.522(5)?Å, and β?=?97.985(6)°. Interactions of the complexes with calf thymus DNA (CT-DNA) have been investigated by UV absorption, fluorescence, and cyclic voltammetry; thus, modes of CT-DNA binding for the complexes have been proposed. Furthermore, DNA cleavage activities by the complexes were performed in the absence of any external agents. The influence of complex concentration or reaction time on the DNA cleavage was studied.     

Synthesis,structure, and DNA-binding studies of a dicopper(II) complex with N-phenolato-N′-[2-(dimethylamino) ethyl]oxamide as ligand

A new µ-oxamido-bridged dicopper(II) complex, [Cu₂(pdmaeox)(bpy)(H₂O)](pic)?·?H₂O [H₃pdmaeox?=?N-phenolato-N′-[2-(dimethylamino)ethyl]oxamide, Hpic?=?2,4,6-trinitrophenol, bpy?=?2,2′-bipyridine], has been synthesized and characterized by elemental analyses, molar conductivity measurement, infrared, and electronic spectra studies, and X-ray single-crystal diffraction. The complex crystallizes in the triclinic system, P 1 space group, with crystallographic data: a?=?10.7815(2)?Å, b?=?11.3598(2)?Å, c?=?14.1389(3)?Å, and z?=?2. In [Cu₂(pdmaeox)(bpy)(H₂O)]⁺, one copper(II) resides in the inner site with a square-planar coordination geometry and the other is chelated by the two exo-oxygen atoms of the cis-pdmaeox^3? ligand in a square-pyramidal environment. The Cu···Cu separation through cis-pdmaeox^3? bridge is 5.1834(4)?Å. The crystal structure is stabilized by hydrogen bonds and π–π stacking interactions. The interaction of the dicopper(II) complex with herring sperm-DNA (HS-DNA) has been investigated by electronic absorption titration, fluorescence titration, electrochemical titration, and viscosity measurements. The results reveal that the interaction of the dicopper(II) complex with HS-DNA might be electrostatic binding. The effects of bridging ligand on the interaction of the dinuclear complex with HS-DNA were preliminarily investigated.     

Linear oxalato- and 4,4′-dipyridyldisulfide-bridged copper(II) coordination polymer involving in situ ligand synthesis

The reaction of 1,3-bis(pyridyl-4-ylthio)propan-2-one with Cu(ClO₄)₂?·?6H₂O gave a new complex {[Cu₂(4PDS)₂(ox)(H₂O)₄](ClO₄)₂} _n (4PDS?=?4,4′-dipyridyldisulfide, ox?=?oxalate), with 4PDS and ox being created by the Cu(II)-assisted oxidation of 1,3-bis(pyridyl-4-ylthio)propan-2-one. The complex determined by X-ray crystallography is a 1D polymer, in which metallacycles formed by two 4PDS and two Cu(II) ions are further bridged through ox anions. It crystallizes in the orthorhombic system, space group Fddd, with lattice parameters a?=?15.106(2), b?=?23.667(4), c?=?27.637(3)?Å and Z?=?8.     

Ferromagnetic interactions in a Zn(II)–nitronyl nitroxide complex with dicyanoaurate(I) bridges

A two-dimensional Zn(II)-nitronyl nitroxide radical complex, Zn(NIT4Py)₂[Au(CN)₂]₂ (NIT4Py?=?2-(4′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) was synthesized and characterized by elemental analyses, IR spectroscopy and single-crystal X-ray diffraction methods. The complex is monoclinic, space group C2/c, with a?=?26.294(9), b?=?7.167(2), c?=?18.532(6) Å, β?=?111.758(5)°, V?=?3243.6(18) ų, Z?=?4, and R ₁ [I?>?2σ (I)]?=?0.0348, and has an infinite two-dimensional network motif. Magnetic studies showed ferromagnetic coupling between two radicals through Zn(II).     

Synthesis and crystal structure of a heterobinuclear complex [(PhPPy2)2PdCuCl2]ClO4 (PhPPy2=bis(2-pyridyl)phenylphosphine)

The mononuclear palladium(II) complex trans-[PdCl₂(PhPPy₂)₂] (1) reacts with [Cu(CH₃CN)₄]ClO₄ to afford the heterobinuclear [(PhPPy₂)₂PdCuCl₂]ClO₄·2CH₃CN (2), bridged by two PhPPy₂ ligands in a new mode. Complex 2 crystallizes in space group P2₁/c with a?=?12.947(1), b?=?9.142(1), c?=?33.454(2)?Å, β?=?99.698(1)°. The copper(I) and palladium(II) ions in 2 adopt distorted tetrahedral and square-planar geometry, respectively. At room temperature, the complex is photoluminescent in solution.