Comparative Studies of Some Novel Cu(II) Polymeric Complexes Derived from Cyanoacetylhydrazine (CAH;L). The Role of Solvents Used on the Structure and Geometry of the Isolated Cu²⁺Complexes

Novel polymeric Cu2+ complexes derived from the reaction of cyanoacetylhydrazine (CAH;L) with CuCl2•2H2O in different solvents were synthesized and characterized. The isolated solid polymeric complexes were investigated using modern conventional physicochemical and spectral (IR, 1H-NMR, UV-Vis. ESR, Raman), magnetic and thermal studies. The results revealed that CAH behaves in different ways towards the coordination of the Cu2+ ion. The promotion of solvents to the cyano group was discussed on the basis of the solvent and the Cu2+ ion used. Magnetic and spectral studies suggest octahedral geometry is proposed for the Cu2+ complexes. EPR studies indicate the existence of polymeric complexes depending on the results of g-values. The results suggest that the number of copper atoms ranges from three to twelve atoms. The molecular modeling is drawn and some chemical characteristics are calculated such as chemical reactivity and energy components are investigated between the different types of the ligands.

Synthesis, Characterizations, Biological, and Molecular Docking Studies of Some Amino Acid Schiff Bases with Their Cobalt(II) Complexes

The synthesis and structural characterization of cobalt(II) complexes of amino acid Schiff bases was prepared from Salicylaldehyde and three amino acid (Valine, Leucine, and Isoleucine)?in basic medium. The metal complexes was synthesized by treating an ethanolic solution of the ligand with appropriate amount of metal salts [1:2] [M:L] ratio. The synthesized Schiff bases and their metal complexes have been investigated on the bases of elemental chemical analysis, FTIR, electronic spectral,?1HNMR,?13CNMR, MS, molar conductance and magnetic susceptibility measurements. The electronic spectra of the metal complexes and their magnetic susceptibility measurements suggest octahedral structures are the probable coordination geometries for the isolated complexes. The Schiff bases and their metal complexes were preliminary scanned against various strains of microbes to study their biological effect.

FERROMAGNETICALLY COUPLED Gd(III)Cu(II)Gd(III)TRINUCLEAR COMPLEXES

Three new heterotrinuclear complexes have been synthesized and characterized, namely {[Gd(L)(2)](2)[Cu(pbaOH)]}(ClO4)(4), where pbaOH denotes 2-hydroxy-1,3-propylenebis(oxamato), L stands for 1,10-phenanthroline (phen), 5-nitro-1,10-phenanthroline (NO2-phen) or 2,2'-bipyridyl (bpy). The temperature dependence of the magnetic susceptibility of ([Gd(phen)(2)(ClO4)](2)[Cu(pbaOH)])(ClO4)(2) has been studied in the 4-300K range, giving the exchange integral J = 6.69 cm(-1). This indicates a weak ferromagnetic interaction between the copper(II) and gadolinium(III) ions.

SYNTHESIS AND CARACTERIZATION OF TERNARY COMPLEXES CONTAINING Cu(II),L-HISTIDINE AND NUCLEOTIDE

The ternary complexes containing Cu(II),L-His and nucleotide (5'-GMP and 5'-IMP)were synthesized and characterized.IR and ~1H NMR spectra show that Cu(II)binds to carboxylate oxygen and imidazole nitrogen of L-His and purine N_7 of 5'-GMP and 5'-IMP.The interaction of Cu(II)with Po_3^(2-)of 5'-GMP is present,but that for 5'-IMP is not present.

Kinetic parameters and thermal decomposition for Novel 1,1-Malonyl-bis(4-p-Chlorophenylthiosemicarbazide) and Cu(II), Co(II), Zn(II) and Sn(II) complexes(H₄pClMaTS) synthesized by electrochemical method

Anodic oxidation of Co, Cu, Zn, and Sn metals in an acetone solution of 1,1-malonayl-bis(4-p- Chlorophenylthiosemicarbazide) yields complexes of composition with general formula [Co2(pClMaTS)(H2O)6]·2H2O, [Cu2(pClMaTS)(H2O)6], [Zn2(pClMaTS)(H2O)6] and [Sn2(pClMaTS)(H2O)6]·2H2O. Chelation was investigated based on elemental analysis, conductivity, magnetic moment, spectral (UV-Vis, IR, Raman, 1HNMR, mass), thermal, and ESR studies. The Raman and infrared spectral studies suggests the tridentate behavior of the ligand from each tail. Since the ligand has two thiose- micarbazide groups, it may acts in an SNO tridentate fashion from each side with one of the two metal ions forming a polynuclear complex coordinating through both of the lone pair of electrons the enolic oxygen of the carbonyl group (C=O), the azomethine nitrogen (C=N) and the thioenol form of the thiocarbonyl group (C=S). The differential thermogravimetric analysis (DTG) curves were used to study the decomposition steps of the isolated complexes using Horowitz-Metzger (HM) and Coats-Redfern (CR) methods. The kinetic thermodynamic parameters such as: E*, ΔH*, ΔS*and ΔG* are calculated from the DTG curves.

Two Cu(II)-Nitronyl Nitroxide Complexes Including Cyclic Dimer: Synthesis, Structures and Magnetic Interactions

Using two new flexible and functional nitronyl nitroxide radicals as ligands, two copper (II) complexes {[Cu(hfac)2]3(NITmPhO3Py)2}n (1) and [Cu(hfac)2 (NIToPhO3Py)]2 (2) (NITmPhO3Py = 2-[(3-methoxy-pyridinyl)phen-3-yl]- 4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, NIToPhO3Py = 2-[(3-methoxy-pyridinyl)phen-2-ly]-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, hfac = hexafluoroacetylacetone), have been characterized structurally and magnetically. The X-ray crystal analyses showed that complex 1 displayed a chain polymer structure which formed with {[Cu(hfac)2]3(NITmPhO3Py)2}n due to the cross-linking of two cyclic binuclear fragments {[Cu(hfac)2]2(NITmPhO3- Py)2} via the bridging unit [Cu(hfac)2];complex 2 presented a binuclear cyclic structure [Cu(hfac)2]2(NIToPhO3Py)2. The magnetic behaviors of the two complexes 1 and 2 have been investigated. Magnetic studies showed that antiferromagnetic interactions dominated in complex 1, while there existed ferromagnetic interactions between Cu(II) and coordinated NO group in complex 2.

SYNTHESIS AND STRUCTURE OF Cu(Ⅱ)COMPLEXES BY OXIDATIVE ADDITION OF DIBENZOYL PEROXIDE ON METALLIC COPPER

Dibenzoyl peroxide undergoes oxidative addition on metallic copper powder with 2,2′-bipyridine(or imidazole)in a mixed solvent(methanol and tetrahydrofuran),and affords the Cu(Ⅱ)complexes-[Cu(Ce(C_6H_5COO)_2(2,2'-bipy)]H_2O(1) and[Cu(C_6H_5COO)_2(C_3H_4N_2)_2](2).The structure was solved by direct methods and Fourier synthesis.C_(24)H_(20)N_2O_5Cu (1),Mr=479.78,space group P2(1)/c,a=6.986(7), b=18.833(I),c=17.021(3),α=γ=90°,Z=4,V=2218.1~3,Dc=1.443g/cm\+3,R=0.055 Rw=0.062.Complex(2),C_(20)H_(18)N_4O_4Cu(2),Mr=441.74,space group P2(1)/n,a=8.699(4), b=9.840(6),c=12.399(5),α=γ=90°,β=100.8°,Z=4,V=1010.9~3,Dc=1.654g/cm\+3,R=0.055, Rw=0.062.

Synthesis and Crystal Structure of a Dinuclear Cu(II) Complex with Tridentate Schiff Base and Azido Bridge

A new dinuclear copper(II) complex ([Cu(C12H17N2O)(N3)]2, C24H34Cu2N10O2) has been synthesized and characterized by X-ray structure determination. It crystallizes in the monoclinic system, space group P21/c with a = 18.529(4), b = 10.933(2), c = 14.534(3) ?, β = 111.07(3)°, V = 2748(1) ?3, Z = 4, Mr = 621.69, F(000) = 1288, Dc = 1.503 g/cm3 and μ(MoKα) = 1.590 mm?1. The structure was refined to R = 0.0647 and wR = 0.1846 for 4406 observed reflections (I > 2σ(I)). The asymmetric unit comprises two halfmolecules. The complex is a centrosymmetric dimmer in which the copper atoms are penta-coordinated by three coordination atoms from the corresponding tridentate Schiff base ligand and two bridging azide anions. The Cu(II)…Cu(II) average distance is 3.350(1) ?.

Crystal Structures of Co(Ⅱ) and Cu(Ⅱ) Complexes and Ammonium Salt Involving Ethylenediamine

The Co（II） complex I and ammonium salt II were synthesized from the direct reaction of 1,2-ethylenediamine and cobaltous acetate tetrahydrate and manganese acetate tetrahydrate in anhydrous ethanol. Treatment of N,N＇-bis（salicylidene）ethylenediamine with Cu（OAc）2·H2O results in the formation of Cu（II） complex III. C14H37CoNaO8 （I）： triclinic, space group P1, a = 8.6296（12）, b = 12.0291（17）, c = 12.1108（17） A, α = 75.335（2）, β = 69.991（2）, γ = 72.248（2）°, V= 1109.4（3） A3, Z = 2, ρcaloa = 1.342 g/cm3, the final R= 0.0342 for 4817 observed reflections with I 〉 2σ（I） and Rw = 0.1263 for all data. C6H16N204 （II）： space group P1, a = 5.5513（10）, b = 5.5589（11）, c = 7.4437（14） A, α = 94.332（4）, β = 104.497（4）, γ = 103.487（4）°,V= 214.06（7） A3, Z = 1, ρcalcd = 1.398 g/cm3, the final R = 0.0431 for 829 observed reflections with I〉 2σ（I） and Rw = 0.1263 for all data. C14H37CuN40 （III）, space group P21/n, a = 9.050（9）, b = 18.434（17）, c = 11.659（11） A, β = 107.134（19）°, V= 1859（3） A3, Z = 4, ρcalcd =1.443 g/cm3, the final R = 0.0616 for 3308 observed reflections （O 〉 2σ（I）） and Rw = 0.1229 for all data. Their structures were all determined by X-ray diffraction, elemental analysis and IR.

Synthesis,Structure and Properties of a Novel Copper(Ⅱ)-2,2'- biimidazole Complex-supported Compound:[Cu(H_2biim)_2]{[Cu(H_2biim)_2 ]_2[H_(10)W_(12)O_(44)]}·8H_2O

A new copper（II）-2,2＇-biimidazole metal-organic POMs-supported compound [Cu（H2biim）2]{[Cu（H2biim）212[H10W12O44]}＇8H2O （H2biim = 2,2＇-biimidazole） has been success- fully synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and TG. The crystal adopts space group Pi with a = 11.800（2）, b = 13.437（3）, c = 13.685（3） A, V = 1922.5（7） A3, D,. = 3.507 g/cm3, C36H62Cu3N24W12O52, M,. = 4059.92, F（000） = 1837,μ = 18.796 mm-1, Z = 1, R = 0.0579 and wR = 0.1465 for 8734 observed reflections （I 〉 2σ（I））. X-ray crystallography analysis exhibits that the title compound consists of one [H10W12044]6- polyanion and three [Cu（H2biim）2] units. And significant π-π stacking interactions and intermolecular O-H-,.O or N-H.＇-O hydrogen-bonding interactions lead to a three-dimensional supramolecular framework. Thermal stability and magnetic property of the complex have also been investigated.

Preparation, Characterization and Antimicrobial Studies of Mn(II) and Fe(II) Complexes with Schiff Base Ligand Derived from 2-aminophenol and 3-formyl-2-hydroxy-6-methoxyquinoline

Schiff base derived from 2-aminophenol and 3-formyl-2-hydroxy-6-methoxyquinoline and its Mn(II) and Fe(II) complexes were synthesized and characterized by melting point and decomposition temperature, elemental analysis, molar conductivity, infrared (IR) spectral analysis, atomic absorption spectroscopy (AAS) analysis, solubility test, and magnetic susceptibility. The Fourier-transform infrared spectroscopy (FTIR) spectral data of the Schiff base determined showed a band at 1622 cm−1 and this was assigned to the v (C=N), which is a feature of azomethine group. The same band was observed to shift to lower frequencies 1577 and 1599 cm−1 in the complexes suggesting coordination of the Schiff base with the respective metal(II) ions. Molar conductance values 14.58 and 12.65 Ω−1∙cm2∙mol−1 show that the metal complexes were non-electrolyte in nature. The magnetic susceptibility of the complexes was determined and the gram magnetic susceptibility of the complexes was found to be positive, revealing that they are paramagnetic. The elemental analysis of the complexes for C, N and H determined suggested 1:1 metal to ligand ratio. The result of the antimicrobial studies showed that, the metal(II) complexes exhibited better antibacterial and antifungal activity than the Schiff base.

Synthesis and Crystal Structure of a Dinuclear Cu(II) Complex [Cu(C_(12)H_(17)N_2O)(NCS)]_2 with Tridentate Schiff Base Ligand N-(Salicylidene)-3-dimethylaminopropylamine

A new dinuclear copper(II) complex (Cu(C12H17N2O)(NCS)2, C26H34Cu2N6O2S2) has been synthesized and characterized by X-ray structure determination. It crystallizes in the triclinic system, space group P1 with a = 11.289(2), b = 12.071(2), c = 12.113(2) ?, α = 72.90(3), β = 83.76(3), γ = 65.60(3)°, V = 1436.7(5) ?3, Z = 2, Mr = 653.79, F(000) = 676, Dc = 1.511 g/cm3, μ(MoKα) = 1.660 mm?1, the final R = 0.0334 and wR = 0.0856 for 5047 observed reflections (I > 2σ(I)). The asymmetric unit comprises two half-molecules. The complex is a centrosymmetric dimmer in which each copper(II) is coordinated in the equatorial plane to the N-(salicylidene)-3- dimethylaminopropylamine ligand through the deprotonated phenolic oxygen atom as well as the nitrogen atoms of imine and amine. The fourth coordination site is occupied by the nitrogen atom of NCS?, while the axial one by the symmetrically related phenoxy oxygen of the other monomeric unit. The Cu(II)…Cu(II) average distance is 3.110(1) ?.

Synthesis,Structure and Magnetism of Two Cu(Ⅱ) 4,5-Dichlorophthalate Complexes

Two 4,5-dichlorophthalate-based metal complexes, {[Cu（bipy）（dcpa）].H2O}n, （1） and {[Cu2Coipy）2（Hdcpa）3]·H2O·C2H5OH.Hdcpa} （2, H2dcpa = 4,5-dichlorophthalic acid and bipy = 2,2＇-bipyridine）, were synthesized and characterized structurally and magnetically. Complex 1 is of orthorhombic system, space group Fdd2 with a = 20.5821（8）, b = 20.9013（12）, c = 17.0270（7） A, V= 7324.9（6） A3, Dc = 1.707 g/cm3, Mr = 470.74, Z = 16, F（000） = 3792, p = 1.519 mm^-1, the final R = 0.0223 and wR = 0.0549 for 9239 observed reflections with I〉 2σ（I）. Complex 2 crystallizes in triclinic, space group P1 with a = 14.1439（12）, b = 14.2981（12）, c = 15.1054（14） A, a = 72.121（2）, β = 77.703（2）,γ = 81.829（2）°, V= 2830.9（4） A3, Dc = 1.689 g/cm3, M,. = 1439.55, Z = 2, F（000） = 1452,μ = 1.207 mm^-1, the final R = 0.0536 and wR = 0.0981 for 16422 observed reflections with 1 〉 2σ（I）. Complex 1 exhibits a diamond-like framework with centrosymmetric binuclear subunits extended by pairs of doubly deprotonated dcpa2- linkers. By contrast, 2 is an asymmetric binuclear entity bridged by carboxylate group of mono deprotonated Hdcpa- ligands. Weak anti- and ferromagnetic interactions are respectively mediated in the carboxylate aggregated binuclear subunits of 1 and 2.

SYNTHEIS， SITUCTURE AND CHARACTERIZATION OF BINUCLEAR Cu（II） COMPLEX ［Cu（C6H5COO）2（C5H6N2）］2．（C4H8O）2

At room temperature,dibenzoyl peroxide undergoes oxidative addition on metallic Copper Powder and 2-aminopyridine in a solvent(acetone and tetrahydrofuran), which affords the product as a binuclear Cu(II)complex [Cu (C5 H5 COO)2(C5 H5 N2)]2. (C4 H5 O)2. The structure of the complex was characterized by elemental analyses. IR spectra, TG-DTA. The structure of the compound has been solved by direct method and Fourier synthesis, and refined by block-diagonal and full matrix least-squares method to a final R of 0.04329 for 3671 independent reflection of I>e(I). The crystals are triclinic, C46H45N4O10Cu2.Z=1, Mr=943.93, space group P-1, with cell parameters, a=10.806(1); b=11.169(3);c=11.729(2)A; α=71.99(2),β=89.38(1)°; γ=81.37(1); V=1330.1A3; Dc=1.172g.cm-3;μ=8.5cm-1. The copper(II) ion is coordinated by four bridging bidentate benzoate and two 2-aminopyridine to form dimeric molecules.

CRYSTAL STRUCTURE OF A 2D SHEET－LIKE μ－CYANIDO－OXAMIDATO BRIDGED Fe（III）－Cu（II） HETERNUCLEAR COMPLEX

The synthesis is and crystal structure are reported for the sheet-like compourd [CU2(oxpn)Fe(CN )5(NO)]. there oxpn is the dianion of M, M'-bis(3-aminopropyl)oxamide. This compound crustallizes in the orthogonal space group Puma. with a=11 .413(4), b=22.242(5), c=7.736(2) A, and Z=4.The structure was refined to conventionat discrepancy factors R=0.047 and Pw=0.054. The Cu(II ) and Fe(III)centers are bridged by oxpn and cyanide, the formal behaves as a his-terdentate tigand bound to cooper(II)ion to form (II) dimers. whereas the latter bridges Cu(II) and Fe(III) centers in both symmetric and asymetric end- to-end bis-monodentate fashions, spreading out along be plane to form a 20 network. The Structure is made up of CuFe unit with Cu(II) and Fe(III) ions locating in a distorted square-based pyramid and a compressed octahedron, respectively.

Synthesis, Characterization and Biological Activity Studies on Novel 4-Chloro-2- [(1-Phenyl-1H-Tetrazol-5-Ylimino)-Methyl] Phenol and Its Metal Complexes

Novel 4-Chloro-2-[(1-phenyl-1H-tetrazol-5-ylimino)-methyl] phenol (Cl-PTMP) and its transition metal complexes were synthesized and characterized by FT-IR, 1H-NMR, UV-Vis spectroscopy, Mass spectrometry, TGA and SEM. The pH-metric technique was applied to get an insight of the number of dissociable protons and protonation sites in candidate compound. The pH-Metric studies were also carried out in presence of metal ions to establish the formation of corresponding metal complexes in solution. Further, the metal ligand compositions of Cu (II) and Co (II) complexes were determined spectrophotometrically by employing Job’s continuous variation method. To know the molecular properties in title imine compound suitable for metal ion coordination, the computational studies were carried out by employing HyperChem 7.5 tools. The energies of HOMO and LUMO frontier orbitals and their electron density contour maps were generated with geometry optimized molecule. Biological activity of Cl-PTMP and its metal complexes was investigated by disc diffusion method.

Spectral, Thermal and Antibacterial Studies for Bivalent Metal Complexes of Oxalyl, Malonyl and Succinyl-bis-4-phenylthiosemicarbazide Ligands

The thermogravimetry (TG) and derivative thermogravimetry (DTG) have been used to study the thermal decomposition of some oxalyl (H4OxTSC), malonyl (H4MaTSC) and succinyl-bis-4-phenyl- thiosemicarbazide (H4SuTSC) ligands and their metal complexes using Horowitz-Metzger (HM) and Coats-Redfern methods. The kinetic thermodynamic parameters such as: E*, ΔH*, ΔS*and ΔG* are calculated from the DTG curves. The isolated complexes have the general composition [M2(L) (H2O)6], where M=Cu(II), Zn(II), L=MaTSC and M=Co(II), Cu(II) or Sn(II) and L=Su TSC and [M2(L) (H2O)n]·nH2O where M=Cu(II), Co(II) or Sn(II), L=OxTS or Ma TSC. The tested compounds show a good activity against four strains of bacteria Gram negative Escherichia coli, Pseudomonas aeruginosa species and gram-positive Bacillus cereus and Staphylococcus aureus.

Adsorption of Cu(II) on maghnite from aqueous solution: Effects of pH, initial concentration, interaction time and temperature

The adsorption behaviour of Cu2+ onto maghnite was conducted under batch conditions. The effect of time, pH of the dispersion, temperature and initial metal concentration on the adsorption of Cu2+ onto maghnite was investigated. In this study, 94% of Cu(II), was adsorbed on the maghnite clay when the equilibrium was reached at 120 min. The adsorption of Cu2+ was a fast process that followed the pseudo-second-order kinetics. This process could be described by the Langmuir model and gave a maximum Cu2+ adsorption capacity of 21.78 mg/g at 293 K. The thermodynamic parameters such as variation of enthalpy ΔH, variation of entropy ΔS and variation of Gibbs free energy ΔG were calculated from the slope and intercept of lnKd vs. 1/T plots. The adsorption was endothermic reaction. The adsorption process for this natural maghnite is more spontaneous because the values of ΔG are less negative. The results suggested that natural maghnite was suitable as sorbent material for the recovery and adsorption of metal ion from aqueous solutions.

A Three-dimensional Porous Metal-organic Framework Based on Cyano Unit and 1,4-Bis(1,2,4-triazol-1-yl)butane(btb):{[Cu_8(btb)_2(CN)_8].3H_2O}_n

The title coordination polymer 1,{[Cu8（btb）2（CN）8].3H2O}n（btb = 1,4-bis（1,2,4-triazol-1-yl）butane）,has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction.Complex 1 crystallizes in monoclinic,space group C2/c with a = 1.2938（3）,b = 1.9422（5）,c = 0.9406（2） nm,β = 121.891（4）°,V = 2.0066（9） nm3,C24H30Cu8N20O3,Mr = 1155.00,Dc = 1.912 g/cm3,μ（MoKα） = 4.209 mm？1,F（000） = 1140,GOF = 1.184,Z = 2,the final R = 0.0634 and wR = 0.1503 for I 2σ（I）.In complex 1,one-dimensional CuCN zigzag chains are linked by triazolyl groups of btb ligands to form two-dimensional networks,which are further bridged by 1,4-butyl moieties of btb ligands to fabricate a three-dimensional order framework,in which one-dimensional ellipsoid-like channels are observed.