Structure of Dicopper Complexes of N,N,N',N'-Tetrakis[(2-benzimidazolyl)methyl]-2-hydroxy-1,3-diaminopropane with Coordinated Thiocyanate Counterions

The structures of five dicopper complexes of binucleating ligand HL-H (N,N,N',N'-tetrakis[(2-benzimidazolyl)methyl]-2-hydroxy-1,3-diaminopropane) with thiocyanate and some other counterions were investigated by the X-ray diffraction method. In Cu(2)(HL-H)(NCS)(2)Cl(2).6H(2)O.CH(3)OH, 1 (a = 12.524(5) ?, b = 14.429(4) ?, c = 16.343(3) ?, alpha = 109.01(2) degrees, beta = 92.62(2) degrees, gamma = 115.27(3) degrees, Z = 2, triclinic, P&onemacr;), one chloride is not coordinated. Distorted square pyramidal (SP) geometry is found for both CuN(3)ClN and CuN(3)ON coordination sites in which the N(3) tripodal coordination sites come from the two symmetric halves of HL-H and the other nitrogen atoms come from thiocyanate ions. In Cu(2)(HL-H)(NCS)(2)(ClO(4))(2).6H(2)O.2EtOH, 2 (a = 10.955(2) ?, b = 15.366(5) ?, c = 18.465(9) ?, alpha = 65.57(4) degrees, beta = 89.73(3) degrees, gamma = 79.81(2) degrees, Z = 2, triclinic, P&onemacr;), the coordination environments for the two copper ions are both CuN(3)ON. However, their geometries are different: one is distorted SP and the other is distorted trigonal bipyramid (TBP). In Cu(2)(HL-H)(NCS)(2)(ClO(4))(2)Cl.H(3)O.3.5H(2)O, 3 (a = 11.986(6) ?, b = 12.778(5) ?, c = 17.81(1) ?, alpha = 82.41(4) degrees, beta = 75.44(5) degrees, gamma = 78.46(4) degrees, Z = 2, triclinic, P&onemacr;), the chloride ion does not coordinate to copper ion, but it is hydrogen bonded to the hydroxy hydrogen. The coordination environments for the two copper ions are both CuN(3)ON with distorted SP geometries. In Cu(2)(HL-H)(NCS)Cl(3).6H(2)O, 4 (a = 12.026(5) ?, b = 14.369(6) ?, c = 16.430(6) ?, alpha = 111.64(3) degrees, beta = 90.51(4) degrees, gamma = 113.90(3) degrees, Z = 2, triclinic, P&onemacr;), one chloride does not coordinate. The coordination environments for the two copper ions are CuN(3)ON in severely distorted TBP geometry and CuN(3)Cl(2) in SP geometry. In Cu(2)(HL-H)(NCS)(3)OH.2H(2)O.3CH(3)OH.Et(2)O, 5 (a = 18.322(5) ?, b = 15.543(6) ?, c = 19.428(7) ?, beta = 102.78(3) degrees, Z = 4, monoclinic, P2(1)/c), the hydroxide ion does not coordinate. The coordination environments for the two copper ions are CuN(3)N(2) with a geometry inbetween SP and TBP but slightly closer to SP and CuN(3)ON in distorted SP geometry. The distances between the copper ions are in the range 4.45-7.99 ?, indicating negligible interaction between the copper ions. The hydroxy groups of HL-H in 1-5all coordinate to copper ions either in a terminal mode (in complexes 1, 4, and 5, denoted as OHR(t)) or in a bridging mode (in complexes 2 and 3, denoted as OHR(b)). These hydroxy groups do not lose their protons in all cases. All thiocyanate anions coordinate to copper ions through nitrogen atoms. All copper ions in 1-5 are pentacoordinated. The fact that the CuN(3) geometries of the tripodal coordination sites in HL-H do not allow the formation of a square planar complex, may be the driving force for the formation of pentacoordinated complexes. From the structurally known dicopper complexes of the HL-H type ligands, the relative coordinating abilities of ligands to CuN(3) are OHR(t) > NCS(-) > Cl(-)(t) > OHR(b) approximately Cl(-)(b), where the letters b and t in parentheses denote bridging and terminal coordination modes respectively.     

Spectroscopic, thermal and voltammetric studies of crystalline complex trans-N,N'-bis(salicylidene)-1',2'-cyclohexanediamine with Cu(II)

The dimeric complex, [C20H20CuN2O2]2, has been prepared and characterized by thermal analysis, IR spectroscopy and single-crystal X-ray diffraction techniques. The Cu atom in the binuclear complex exists in a distorted square-pyramidal configuration, defined by three O atoms and two N atoms. The crystal structure is stabilized by intermolecular C-H...O hydrogen bonding interaction. The electrochemical property of the complex was investigated in CH2Cl2 by cyclic voltammetry at 100 mV s(-1) scan rate.     

Mixed-valence copper coordination polymers based on CuSCN or CuN_3 as bridging motifs

Two novel mixed valence copper coordination polymers, [Cu(2-pac)2(CuN3)(H2O)]n (1) and [Cu(2-pac)2(CuSCN)2]n (2), have been prepared through hydrothermal synthesis and analyzed for structure determination, which exhibit two and three-dimensional structures respectively. In complex (1), zigzag chains of [CuN3]n running parallel to the c direction are interconnected by Cu(2pac)2 to form a two-dimensional layer structure. In complex (2), the arrangement ofμ-1,1,3 bridging thiocyanate ligand leads to the formation of ten-membered Cu-SCN-Cu-S-Cu-NCS rings, and each Cu atom is further linked by Cu(2-pac)2 to afford a three-dimensional configuration.     

Synthesis and Structural Characterization of a Copper Complex with Furaldehyde Salicylylhydrazone

The copper complex Cu（C12H9N2O3）2 has been synthesized by the reaction of furaldehyde salicylylhydrazone （Hfs） and copper acetylacetonate and characterized by X-ray crystal diffraction and spectroscopic studies. The crystal crystallizes in space group P211n with a = 5.9765（3）, b = 15.7196（9）, c = 12.0514（6）A,β= 101.618（3）^o, V = 1109.0（1）A^3, C24H18CuN4O6, Mr = 521.96, Z = 2, Dc = 1.563 g/cm^3, μ = 1.035 mm^-1, F（000） = 534, R = 0.0373 and wR = 0.1058 for 2283 observed reflections （I 〉 2σ（I））. The copper atom has a square-planar CuN2O2 coordination and should be in an octahedral coordination if considering Cu-O （phenol） with distances of 2.796（2）A as weak bonds. The neighboring copper complex molecules are linked together by these weak Cu-O （phenol） bonds, resulting in an extended 1D chain. The title compound exhibits paramagnetic property and fluorescence behavior at room temperature supported by the EPR and fluorescence spectra.     

Solubility of <Emphasis Type="Italic">d</Emphasis>-element salts in organic and aqueous–organic solvents: II. Effect of halocomplex formation on solubility of cobalt bromide and chloride and nickel chloride

Solubility of salts in the systems MCl₂–H₂O–Solv (M = Co, Ni) and CoBr₂–H₂O–Solv (Solv = dimethyl sulfoxide, dimethyl formamide, and dimethyl acetamide) at 25°C was measured experimentally. Dominating species of cobalt and nickel halides existing in various concentration regions were identified by analysis of electron absorption spectra. It was shown that the major factor defining solubility is the interaction of halocomplexes of metal ions with solvent molecules.     

Photoluminescence of the Coordination Zinc Compounds with 3-Methyl-4-Formyl-1-Phenylpyrazol-5-one Acylhydrazones

Russian Journal of Coordination Chemistry - New coordination zinc compounds based on 3-methyl-4-formyl-1-phenylpyrazol-5-one acylhydrazones [Zn(L)(CH3COO)Solv] (Solv is H2O (I), Py (II)) are...     

A Cu(Ⅱ) Complex with IM-MeImz-к2 N,O Mode in [Cu(IM-MeImz)2]·(SCN)2: Synthesis, Crystal Structure and Magnetic Properties

A new copper(Ⅱ) compound with imino nitroxide radicals [Cu(IM-MeImz)2]·(SCN)2 (IM-meImz =2-(5-methylimidazol-4-yl)-4,4,5,5-tetramethyl-2-imidazoline-1-oxyl) has been synthesized and characterized structurally and magnetically. It crystallizes in monoclinic, space group P21/c with a = 9.3604(7), b = 10.3012(7), c = 16.6684(12) (A), β = 105.0290(10)°, V = 1552.25(19)(A)3, C24H34CuN10O2S2, Mr = 622.27, Z = 2, Dc = 1.331 g/cm3, μ(MoKα) = 0.876 mm-1, F(000) =650, the final R = 0.0374 and wR = 0.1079. X-ray analysis demonstrates that the IM-MeImz ligand is coordinated to the copper(Ⅱ) ion as an unusual didentate chelate with a κ2 N(MeImz),O(IM) mode in the complex. The square-planar coordination sites at Cu(Ⅱ) are occupied by two O and two N atoms from the imino nitroxide radicals. The complex molecules are connected as a onedimensional polymer structure by intermolecular interactions. Magnetic measurements show that there are intramolecular antiferromagnetic interactions between the Cu(Ⅱ) ion and radicals.     

A Cu(II) Complex with IM-MeImz-κ~2 N,O Mode in [Cu(IM-MeImz)_2]·(SCN)_2: Synthesis, Crystal Structure and Magnetic Properties

A new copper(II) compound with imino nitroxide radicals [Cu(IM-MeImz)2]?(SCN)2 (IM-meImz =2-(5-methylimidazol-4-yl)-4,4,5,5-tetramethyl-2-imidazoline-1-oxyl) has been synthesized and characterized structurally and magnetically. It crystallizes in monoclinic, space group P21/c with a = 9.3604(7), b = 10.3012(7), c = 16.6684(12) , β = 105.0290(10)o, V = 1552.25(19) 3, C24H34CuN10O2S2, Mr = 622.27, Z = 2, Dc = 1.331 g/cm3, μ(MoKα) = 0.876 mm-1, F(000) = 650, the final R = 0.0374 and wR = 0.1079. X-ray analysis demonstrates that the IM-MeImz ligand is coordinated to the copper(II) ion as an unusual didentate chelate with a κ2 N(MeImz),O(IM) mode in the complex. The square-planar coordination sites at Cu(II) are occupied by two O and two N atoms from the imino nitroxide radicals. The complex molecules are connected as a onedimensional polymer structure by intermolecular interactions. Magnetic measurements show that there are intramolecular antiferromagnetic interactions between the Cu(II) ion and radicals.     

Thermodynamics of Transfer of Atomic and Molecular Species into Binary Solvents

A method was suggested for separation of the Gibbs energy of transfer of atomic, molecularspecies from a solvent Solv1 into a binary solvent (Solv1 + Solv2) into the contribution from solvation of thereaction centers and that from nonspecific interactions, solvent reorganization, and cavity formation. The relationship for calculating the former contribution can be used for thermodynamically adequate comparative estimation of the stability of complex species in solution.     

A 2-D Copper Coordination Polymer [Cu(4,4''''-bpy)(H_2O)_4](C_4H_2O_4)(H_2O)_4 Integrated by Hydrogen Bonds and VDW Interactions

1 INTRODUCTION A great deal of interest in transition metal com- plex assembly has recently been devoted to the development of rational synthetic routes to novel one-, two- and three-dimensional crystal frameworks, due to their potential applications in…     

Efficient visible light induced nuclease activity of a ternary mono-1,10-phenanthroline copper(II) complex containing 2-(methylthio)ethylsalicylaldimine

Ternary Schiff base copper(II) complex [CuL(phen)](ClO(4)), where HL is 2-(methylthio)ethylsalicylaldimine and phen is 1,10-phenanthroline, has been prepared and structurally characterized by X-ray crystallography. The complex shows a CuN(3)OS coordination in a square-pyramidal (4 + 1) geometry with the sulfur as an equatorial ligand. The complex is an avid binder to double-stranded DNA in the minor groove and exhibits both photonuclease and chemical nuclease activity. When exposed to UV light of 312 nm (96 W) or visible light of 532 nm (125 W) under aerobic conditions, the complex causes significant cleavage of supercoiled pUC19 DNA in the absence of any externally added reducing agent or H(2)O(2).     

Microsolvation of the [Ni(acac)(tmen)]+ complex

Microsolvation of the [Ni(acac)(tmen)]⁺ complex by a series of aliphatic n-alcohols (Solv) has been studied in ClCH₂CH₂Cl solutions by spectrophotometry. Based on the changes in the electronic spectrum of the afore-mentioned complex, observed under the influence of any alcohol, the equilibrium constants for the formation of the [Ni(acac)(tmen)Solv]⁺ and [Ni(acac)(tmen)Solv₂]⁺ species have been computed according to the algorithm presented in this work. It was found that, in all the systems studied, the stability of five-coordinated [Ni(acac)(tmen)Solv]⁺ is higher than that of octahedral [Ni(acac)(tmen)Solv₂]⁺. The resulting values are discussed in terms of the Lewis basicity of alcohols.     

Spectroscopic properties and coordination structure studies on the [Cu(l-Glu)(Im)] complex

Summary The electronic absorption spectrum and photoacoustic absorption spectrum of (l-glutamato)(imidazole)copper(II) were recorded and the results are discussed quantitatively with respect to ligand field theory and the radial scaling wave function of a non-free copper(II) ion. The axial interactions are discussed by comparing experimental with calculated values according to CuN(2)O(2) and CuN(2)O(3) chromophores, respectively, and by the bond-strength analysis.Author to whom all correspondence should be directed.     

Relationship between the thermally induced reorientations of aromatic solvate molecules in Cu(hfac)2-nitroxide breathing crystals and the character of the magnetic anomaly

A new group of "breathing" crystals has been synthesized. These are aromatic solvates of the copper(II) hexafluoroacetylacetonate complex with spin-labeled pyrazole Cu(hfac)(2)L·0.5Solv, where L is 2-(1-butyl-1H-pyrazol-4-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl and Solv is benzene, toluene, ethylbenzene, propylbenzene, butylbenzene, styrene, o-xylene, m-xylene, p-xylene, 1,4-bis(trifluoromethyl)benzene, 1-methyl-4-ethylbenzene, 1-methyl-4-vinylbenzene, 1,4-diethylbenzene, 1,2,3-trimethylbenzene, or 1,2,4-trimethylbenzene. The main feature of Cu(hfac)(2)L·0.5Solv single crystals is their remarkable mechanical stability and ability to undergo thermally induced structural rearrangements accompanied by spin-crossover-like phenomena. The structures of Cu(hfac)(2)L·0.5Solv solvates are similar and based on mutually parallel {Cu(hfac)(2)L}(∞) heterospin chains with a "head-to-head" motif. The localization of voids with guest molecules being the same in all crystals, the temperature dependence of the effective magnetic moment (μ(eff)) for Cu(hfac)(2)L·0.5Solv is determined by the structure of the guest molecules, along which the polymer chains are "gliding" when the temperature changes. When the temperature decreased from 300 to 100-50 K, μ(eff) decreased, abruptly or gradually, from 2.7-2.4 to ~1.8 β for the majority of Cu(hfac)(2)L·0.5Solv except the solvates with benzene, toluene, and 1,4-bis(trifluoromethyl)benzene. When Cu(hfac)(2)L·0.5C(6)H(6) and Cu(hfac)(2)L·0.5CH(3)-C(6)H(5) were cooled to 50 K, μ(eff) decreased to ~2.1-2.2 β. When Cu(hfac)(2)L·0.5(1,4-(CF(3))(2)-C(6)H(4)) was cooled to 50 K, μ(eff) initially decreased from ~2.7 to 1.9 β and then abruptly increased to ~2.4 β. A single-crystal X-ray diffraction analysis of each solvate within a temperature range wider than the range of magnetic anomaly temperatures revealed a complex interrelated dynamics of the aromatic solvent guest molecules and heterospin chains. The dynamics largely depended on the orientation of the solvent guest molecules relative to the polymer chains. An analysis of the thermally induced phase transformations revealed a relationship between the structural rearrangement of Cu(hfac)(2)L·0.5Solv and the form of the magnetic anomaly on the μ(eff)(T) curve and between the structural rearrangement of the solvate and the temperature of the magnetic effect.     

[Cu(PTA)(Phen)2](p-MBA)(H6O)配合物的合成、晶体结构及电化学分析

The crystal structure of the title complex with the stoichiometric formula [Cu(PTA)(Phen)₂](p-MBA)(H₆O) (Phen=1,10-phenanthroline, PTA=terephthalic acid, p-MBA=p-toluic acid) has been determined by single-crystal X-ray diffraction. The crystal (C₄₈H₄₀CuN₄O₁₀, M_r=896.38) belongs to the monoclinic space group C2/c, with the following crystallographic parameters: a=1.778 6(3) nm, b=1.912 5(3) nm, c=1.389 9(2) nm, β=114.686(2)°, V=4.295 7(12) nm³, D_c=1.386 g·cm^-3, Z=4, μ(Mo Kα)=0.574 mm^-1, F(000)=1 860, final GooF=1.019, R=0.054 0, wR=0.148 3 for 2 644 observed reflections (I>2σ(I)). The crystal structure shows that the copper(Ⅱ) ion is coordinated with two oxygen atoms from one terephthalic acid molecule and four nitrogen atoms from two 1,10-phenanthroline molecules, forming a distorted octahedral coordination geometry. The cyclic voltametric behavior of the complex is also reported. CCDC: 298809.     

Ungewöhnliche Molekülstrukturen für Platin(II)-at-Komplexe

Unusual Structures of Platinum(II)-ate Complexes X-ray investigations at Pt^II-ate complexes of the type “Li₂[Pt(CH₃)₄](Solv.)₂” revealed a new structure type of organometallic compounds of platinum(II). The synthesis of the highly reactive compounds [Li₂{Pt(CH₃)₄}(Solv.)₂]_n (Solv. = Et₂O, THF, n = 2; TMEDA, PMDTA; n = 1) as well as studies by NMR and DTA will be described.     

Hydrogen-Bonded Aggregates of Scandium(III) Complexes

The influence of the concentration of halide ions and concentration of an organic component (Solv) in solutions on the composition, coordination number, and structure of the scandium(III) complexes in solutions and in crystal is studied. The ⁴⁵Sc NMR data show that the main factor determining Cl^– coordination in the Sc³⁺–Cl^––H₂O–Solv systems is the Solv concentration. According to the X-ray diffraction analysis data, at the molar ratios of X^– : Sc³⁺ < 3 (X^– = Cl, Br), the [Sc(OH)(H₂O)₅]₂X₄ · 2H₂O salts with a coordination number of Sc 7 are isolated from solutions in H₂O and alcohols (coordination core is ScO₇ and X^– ions are not involved in coordination). Supramolecular H-bonded aggregates containing the ScCl₃(H₂O)₃ molecular complex with coordination number of Sc 6 and meridianal arrangement of analogous ligands are isolated from solutions with the Cl^– : Sc³⁺ molar ratios from 3 to 20 (in concentrated HCl) using macrocyclic molecules (1,4,7,10,13,16-hexaoxocyclooctadecane (18C6) and 1,4,10,13-tetraoxo-7,16-diazacyclooctadecane (DA18C6)).     

Syntheses and Crystal Structures of Mono-and Binuclear Copper(Ⅱ) Mixed-ligand Complexes Involving Schiff Base

1 INTRODUCTION The chemistry of copper compounds has been extensively investigated and the relationship be- tween structure and reactivity, ranging from indus- trial catalysis to biochemistry activity, is of major importance. For binuclear copper(II) complexes equa- torially bridged by pair of hydroxide[1] or alkoxide[2, 3] groups, satisfactory linear correlation is found be- tween the Cu–O–Cu bridging angle and spin coupling between the metal centers. However, for binuclear copper(I…     

Synthesis and Crystal Structure of a New Mononuclear Copper（Ⅱ） Complex with 4,4′,6,6′-Tetrabromo-2,2′- [ethylenedioxybis（nitrilomethylidyne）]diphenol

A new mononuclear Cu（II） complex, [Cu（L）] （H2L = 4,4′,6,6v-tetrabromo-2,2′- [ethylenedioxybis（nitrilomethylidyne）]diphenol）, has been synthesized and structurally characterized. X-ray crystal structure of the complex reveals that the Cu（Ⅱ） ion is four-coordinated by two oxygen atoms and two nitrogen atoms from L2- unit. Crystallographic data： monoclinic, space group P21/n with a = 14.076（2）, b = 6.9801（14）, c = 19.858 （2） A, β= 107.613（2）°, C16n10Br4CuN2O4, Mr = 677.44, V = 1859.6（5） A3, Dc = 2.420 g/cm3,μ = 9.796 mm^-1, F（000） = 1284, Z = 4, the final R = 0.0516 and wR = 0.0938 for 1879 observed reflections with I 〉 2σ（/）. The dihedral angel between the two coordination planes of Cu（1）-N（2）--O（4） and Cu（1 ）-N（ 1 ）-O（3）） is 30.08（6）°.     

Syntheses and Crystal Structures of Mono- and Binuclear Copper( Ⅱ ) Mixed-ligand Complexes Involving Schiff Base

The mononuclear copper(Ⅱ) complex [Cu(L)(2-AP)] 1 and binuclear copper(Ⅱ)complex [Cu(L)(py)]2 2 (L = C1oH1 1O5NS, taurine o-vanillin, py = prydine, 2-AP = 2-aminopyridine)with mixed ligand have been synthesized and characterized by X-ray diffraction method. Crystal data for 1: orthorhombic, space group Pbca with a = 11.921(4), b = 15.816(6), c = 17.076(6) (A), V=3219.7(19) (A)3, C15H17CuN3O5S, Z = 8, Mr = 414.92, Dc = 1.712 g/cm3,μ(MoKα) = 1.520 mm-1,F(000) = 1704, the final R = 0.0300 and wR = 0.0705 for 2840 observed reflections with I ＞ 2σ(I);and crystal data for 2: monoclinic, space group P21/c with a = 7.929(3), b = 17.038(5), c = 11.734(4)(A), β = 98.162(6)°, V = 1569.1 (9) (A)3, C15H16CuN2O5S, Z = 4, Mr = 399.90, Dc = 1.693 g/cm3, F(000)= 820,μ(MoKα) = 1.554 mm-1, the final R = 0.0351 and wR = 0.0848 for 2767 observed reflections (I ＞ 2o(I)). The molecular structure of complex 1 consists of one tetra-coordinated Cu(Ⅱ) atom generating a slightly distorted square plane, and a one-dimensional chain structure is formed by intermolecular hydrogen bonds. Complex 2 consists of a diphenolic hydroxyl O-bridged binuclear copper(Ⅱ) structure. The crystal structures of complexes 1 and 2 reveal that the coordinate copper centers are bound to both nitrogen and oxygen atom donors. The usual N,O-trans arrangement of ligands is observed in both cases.