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1.
The synthesis and characterization of [Cu(4-MeOsal)2(2-pyme)2] (1) and [Cu(3-Mesal)2(2-pyme)2] (2) (where 4-MeOsal?=?4-methoxysalicylate, 3-Mesal?=?3-methylsalicylate and 2-pyme?=?2-pyridylmethanol) are reported. The composition and stereochemistry as well as the mode of coordination have been determined by elemental analysis, IR, electronic and EPR spectra as well as magnetization measurements over the temperature range 1.8–300?K. The crystal structures of Cu(4-MeOsal)2(2-pyme)2 and Cu(3-Mesal)2(2-pyme)2 have been determined.  相似文献   

2.
The syntheses and characterizations of salicylatocopper(II) complexes of the formula Cu(X-sal)2(2-pyme)2 (X = 3-MeO (1), 4-MeO (2), 3-Me (3), 4-Me (4) and 5-Me (5), where 3-MeOsal = 3-methoxysalicylate, 4-MeOsal = 4-methoxysalicylate, 3-Mesal = 3-methylsalicylate, 4-Mesal = 4-methylsalicylate, 5-Mesal = 5-methylsalicylate anion, and 2-pyme = 2-pyridylmethanol) are reported. The composition was determined by elemental analysis, and ligand coordination modes have been determined by spectroscopic methods (IR, UV-VIS). The crystal structure determination of [Cu(3-MeOsal)2(2-pyme)2] (1) and [Cu(5-Mesal)2(2-pyme)2] (5) have confirmed conclusions originally based on spectral data. EPR measurements of frozen water/methanol solutions containing different copper(II): 2-pyme molar ratios have indicated presence of complexes with only two nitrogen donor atoms bonded to each central atom.   相似文献   

3.
Investigation of salicylatocopper complexes in the presence of a nitrogen donor ligand is a growing research area due to the interesting mimetic activities of such complexes. Here, three X-salicylatocopper (where X = 3-methyl, or 4-methoxy) complexes with three different N-donor ligands, [Cu(μ-menia)(3-Mesal)2(menia)(H2O)]2 (I), Cu(3-Mesal)2(denia)2(H2O)2 (II), Cu(4-MeOsal)2(2-pyme)2 (III), are presented (where 3-Mesal = 3-methysalicylate, 4-MeOsal = 4-methoxysalicylate, menia = N-methylnicotinamide, 2-pyme = 2-pyridylmethanol). The complexes were characterized by elemental analysis, IR and UV-VIS spectrophotometry. Cyclic voltammetry and the superoxide dismutase activity of the prepared complexes in solution were measured and the complexes were characterized by means of the inhibition concentration IC50. In addition, the superoxide dismutase (SOD) activity of these complexes was compared with those of the parent ligand copper acetate, native SOD enzyme, and the related copper complexes containing non-steroidal anti-inflammatory drugs. The resulting SOD activity was correlated to the composition, structure and redox stability of the prepared complexes. The best value of the inhibition concentration was found for complex I (IC50 = 2.24 µM), which classifies this complex into a group of good superoxide scavengers.  相似文献   

4.
The mixed-ligand 3-hydroxybenzoic acid complex of Zn(II) with nicotinamide and N,N-diethylnicotinamide were synthesized and characterized (colorless single crystals, [Zn(3-hba)2(H2O)2(na)2] and [Zn(3-hba)2(H2O)2(dena)2]). The chemical, FT-IR, thermal, mass spectral analyses, and X-ray data results revealed that both of the compounds contain two water molecules, two 3-hydroxybenzoate (3-hba) and two nicotinamide (na) or two N,N-diethylnicotinamide (dena) ligands per formula unit. 3-hba and na or dena ligands bind to the Zn(II) ion monodentately through their acidic oxygen and pyridinic nitrogen atoms, respectively. The coordination of metal atoms are completed by two molecules of aqua ligands. The charge balance of complexes is accommodated by two molecules of 3-hba ions. The unit cell has two molecules coordination molecules and each of them was as settled to four surfaces of unit cell cage in na complex. There is one mole molecule that was occupied to center of unit cell cage in dena complex. The two dimensional network structure of the complex is like a hexagonal for na and square plane for dena complexes. The thermal decomposition takes place in three steps; first, dehydration of the two aqua ligands, second, elimination of the two nicotinamide ligands, finally, burning of the two benzoate ion ligands.  相似文献   

5.
The synthesis and characterisation of Cu(meclof)2H2O and Cu(meclof)2L2 (meclof = meclofenamate; L = 2-pyridylcarbinol (2-pyca), 3-pyridylcarbinol (3-pyca), nicotinamide (na), N,N-diethylnicotinamide (dena) are reported. The characterisation of the compounds were based on elemental analyses, electronic, IR and EPR spectra. The carboxyl group of the meclofenamate anions coordinates to the Cu(II) atom as an unidentate or as a chelating ligand. The crystal and molecular structures of one of the products, namely Cu(meclof)2(2-pyca)2 were measured. The EPR spectra of the studied complexes show they are monomeric, except for Cu(meclof)2 · H2O which shows triplet state feature. On the basis of the spectroscopic parameters observed, a monomeric structure with a tetragonally Jahn–Teller distorted octahedron around the Cu(II) atom is deduced for Cu(meclof)2L2 and for Cu(meclof)2 · H2O a dimeric structure is proposed. The degree of distortion in the series of the Cu(meclof)2L2 complexes increases in the order of L: na < 2-pyca < 3-pyca < dena.  相似文献   

6.
The synthesis and characterization of four new solid complexes, Cu(tolf)2L2 (tolf = tolfenamate, L = 2-pyridylmethanol (2-pyme), 3-pyridylmethanol (3-pyme), nicotinamide (na)) and Cu(tolf)2(dena)2(H2O)2 (dena = N,N-diethylnicotinamide) is reported. The composition and stereochemistry as well as the mode for ligand coordination have been determined by elemental analysis, IR, electronic and EPR spectra. The carboxyl group of the tolfenamate anion coordinates to the Cu(II) atom as an unidentate or as a chelating ligand. The EPR spectra of the powdered solids are consistent with spin S = ½. The crystal structure of Cu(tolf)2(dena)2(H2O)2 has been determined at 293 K. The Cu(II) atom has a tetragonal–bipyramidal arrangement (CuO4N2). The spectroscopic data indicate that each copper(II) atom in Cu(tolf)2L2 has a tetragonal–bipyramidal environment built up by bidentate unsymmetrically coordinate tolfenamates and unidentate N-donor atom ligands.  相似文献   

7.
Two new uranyl complexes [UO2(DPDPU)2(NO3)2](C6H5CH3) (1) and [UO2(PMBP)2 (DPDPU)](CH3C6H4CH3)0.5 (2), (DPDPU?=?N,N′-dipropyl-N,N′-diphenylurea, HPMBP?= 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5) were synthesized and characterized. The coordination geometry of the uranyl atom in 1 is distorted hexagonal bipyramidal, coordinated by two oxygen atoms of two DPDPU molecules and four oxygen atoms of two bidentate nitrate groups. The coordination geometry of the uranyl atom in 2 is distorted pentagonal bipyramidal, coordinated by one oxygen atom of one DPDPU molecule and four oxygen atoms of two chelating PMBP molecules.  相似文献   

8.
Summary The reaction of monochloropentaphenoxycyclotriphosphazene with 3-(aminomethyl)pyridine yields 3-(aminomethyl)pyridylpentaphenoxycyclotriphosphazene (1), a new N-donor ligand with five nitrogen atoms as potential coordination centers. Complex formation with copper(II) nitrate yields compound2 with the general structure Cu(1)2(NO3)2. The X-ray structure analysis shows that the copper ion is coordinated by two nitrogen atoms of the pyridine rings and four oxygen atoms of the unsymmetrical bidentate nitrate groups in aJahn-Teller distorted octahedral arrangement.
Synthese von 3-(Aminomethyl)pyridylpentaphenoxycyclotriphosphazen und seine Komplexibildung mit Kupfer(II)nitrat. Molekülstruktur von {Cu[N3P3(OC6H5)5(NHCH2(3-C5H4N))]2(NO3)2}
Zusammenfassung Die Reaktion von Monochlorpentaphenoxycyclotriphosphazen mit 3-(Aminomethyl)pyridin ergibt 3-(Aminomethyl)pyridylpentaphenoxycyclotriphosphazen (1), einen neuen N-Donor Liganden mit fünf Strickstoffatomen als potentielle Metallkoordinationszentren. Bei der Umsetzung von1 mit Kupfer(II)nitrat entsteht der Metallkomplex2 mit der Zusammensetzung Cu(1)2(NO3)2. Die durch Röntgenstrukturanalyse ermittelte Molekülstruktur zeigt, daß das Kupferion von zwei Stickstoffatomen der Pyridinringe sowie vier Sauerstoffatomen der unsymmetrisch zweizähnigen NitratgruppenJahn-Teller-verzerrt oktaedrisch umgeben ist.
  相似文献   

9.
Four copper(II) complexes and one copper(I) complex with pyridine-containing pyridylalkylamide ligands N-(pyridin-2-ylmethyl)pyrazine-2-carboxamide (HLpz) and N-(2-(pyridin-2-yl)ethyl)pyrazine-2-carboxamide (HLpz?) were synthesized and characterized. The X-ray crystal structures of [Cu2(Lpz)2(4,4?-bipy)(OTf)2] (1, OTf?=?trifluoromethanesulfonate, 4,4?-bipy?=?4,4?-bipyridine) and [Cu(Lpz)(py)2]OTf·H2O (2, py?=?pyridine) revealed binuclear and mononuclear molecular species, respectively, while [Cu(Lpz)(μ2-1,1-N3)]n (3), [Cu(Lpz?)(μ2-1,3-N3)]n (4), and [Cu(HLpz)Cl]n (5) are coordination polymer 1-D chains in the solid state.  相似文献   

10.
Summary Dimeric and polymeric copper(II) complexes containing BPCA (N-2-pyridinylcarbonyl-2-pyridinecarboximidate), having general formulae Cu(BPCA)X·nH2O (X=Cl, Br, NCS, NCO, N3, or CN) and Cu2(BPCA)2-X·nH2O [X=oxalate anion (OX), chloranilate anion (CA) or the dianion of 2,5-dihydroxy-1,4-benzoquinone (DHBQ)] have been synthesized by the copper(II)-assisted hydrolysis of 2, 4, 6-tris(2-pyridyl)-1, 3, 5-triazine. Spectroscopic results indicate five-coordinate, approximately square-pyramidal, geometry around the copper(II) ion. Half-field absorption in the M s=±2 region of the X-band e.p.r. powder spectra has been observed for the dimeric species.  相似文献   

11.
Nickel(II) and cobalt(II) complexes with optically active diaminodioxime (H2L, the derivative of 3-carene) of the compositions [Ni(H2L)NO3]NO3 (I), Ni(H2L)Cl2 (II), [Ni(HL)]ClO4 · H2O (III), and Co(H2L)Cl2 (IV), were synthesized. According to X-ray diffraction data, the structures of the paramagnetic compound I and diamagnetic complex III are ionic. In the cation of I, the distorted NiN4O2 octahedron is formed by the N atoms of the tetradentate cyclic ligand (H2L molecule) and by the O atoms of NO3 –; anion functioning as bidentate cyclic ligands. In the cation of III, the NiN4 coordination unit is a distorted square formed upon coordination of the tetradentate cyclic ligand, HL–; anion. The data of magnetochemistry and UV-Vis, IR, and Raman spectroscopy suggest that paramagnetic complexes II and IV contain a distorted octahedral polyhedron MCl2N4 (M = Ni, Co).  相似文献   

12.
Reactions of copper salts, zoledronic acid, and 2,2′-bipyridine/1,10-phenanthroline in aqueous ethanolic solutions afforded four phosphonate oxygen-bridged copper complexes, Cu(bipy)(H4zdn)(HSO4) (1), [Cu2(bipy)2(H2zdn)(H2O)(Cl)]·4H2O (2), [Cu2(phen)2(H2zdn)(H2O)(Cl)]·2.5H2O (3), and [Cu3(bipy)3(H4zdn)(H2zdn)(SO4)]·5H2O (4) (H5zdn = zoledronic acid, bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline). The copper centers of 14 have square pyramidal coordination geometries. The Cu(II) ions are coordinated to bipy/phen, zoledronate, and HSO4?/Cl? forming mononuclear units for 1, dinuclear for 2 and 3, and trinuclear for 4. These building units are further extended into 3-D supramolecular networks via multiple hydrogen bond interactions. Temperature-dependent magnetic properties of 2 and 4 suggest weak antiferromagnetic coupling (J = ?4.53(8) cm?1 for 2, J = ?1.69(4) cm?1 for 4). The antitumor activity of 2 was evaluated against the human lung cancer cell line and indicates effective time- and dose-dependent cytotoxic effects.  相似文献   

13.
Tetradentate Schiff-base carboxylate-containing ligands, bis(2-pyridylmethyl)amino-3-propionic acid (Hpmpa) and bis(2-pyridylmethyl)amino-4-butyric acid (Hpmba), react with CuCl2 to give rise to the mononuclear complexes [Cu(Hpmpa)Cl]Cl · 2H2O (1) and [Cu(Hpmba)Cl2]· H2O (2). These complexes have been characterized by X-ray crystallography, spectroscopic and cyclic voltammetry. Crystal structure of (1) shows that the copper(II) ion has a distorted square-pyramidal geometry with the three nitrogen atoms of the Hpmpa ligand and one chloride anion occupying the basal plane and an oxygen atom from the carboxylate group coordinating the axial position. In (2), the coordination environment around the copper(II) ion reveals a distorted square-pyramids with three nitrogen atoms of the Hpmba ligand and one chloride anion that comprise the basal plane, whereas the apical position is filled by the chloride anion. Cyclic voltammetry of the complexes gives two one-electron waves corresponding to CuII/CuIII and CuIII/CuI processes. The electronic spectra and redox potentials of the complexes are influenced significantly by the N-pendant carboxylate groups.  相似文献   

14.
The crystals of copper(I) π-complexes CuBF4 · 2C6H4N3(OC3H5) · H2O (I) and CuCF3COO · C6H4N3(OC3H5) (II) were obtained by alternating-current electrosynthesis and studied by X-ray diffraction: I, space group P21/n, a = 10.226(8), b = 13.233(10), c = 16.30(1) Å, β = 98.13(1)°, V = 2249(2) Å3, Z = 4, R = 0.0705, 577 reflections; I, space group P $ P\bar 1 The crystals of copper(I) π-complexes CuBF4 · 2C6H4N3(OC3H5) · H2O (I) and CuCF3COO · C6H4N3(OC3H5) (II) were obtained by alternating-current electrosynthesis and studied by X-ray diffraction: I, space group P21/n, a = 10.226(8), b = 13.233(10), c = 16.30(1) ?, β = 98.13(1)°, V = 2249(2) ?3, Z = 4, R = 0.0705, 577 reflections; I, space group P , a = 8.8625(7), b = 9.0647(4), c = 9.1650(5) ?, α = 68.37(2)°, β = 85.31(3)°, γ = 69.86(2)°, V = 646(4) ?3, Z = 2, R = 0.1354, 2669 reflections. In compound I, the tetrahedrally distorted trigonal pyramidal environment of the copper atom comprises two nitrogen atoms of two organic molecules (L), the C=C bond of another L molecule, and the O atom of the water molecule. Due to the bridging function of L molecule, infinite chains [Cu · 2C6H4N3(OC3H5) · H2O] n are formed in the structure along the y axis. The chains are, in turn, assembled into layers through strong O-H…F hydrogen bonds involving both hydrogen atoms of the water molecule and fluorine atoms of the BF4 anion. In compound II, two bridging oxygen atoms of two trifluoroacetate anions and two copper atoms form a centrosymmetric dimer. The nitrogen atom of the benzotriazole ring of one molecule L and the C=C double bond of the allyl group of the other molecule L complete the distorted coordination tetrahedron of the metal atom. Owing to the bridging function of the L molecule, the [CuCF3COO · C6H4N3(OC3H5)]2 dimers are connected to form infinite double chains associated in a three-dimensional framework by only weak interactions. The replacement of the covalently bonded trifluoroacetate anion by an outer-sphere tetrafluoroborate ion opens up the possibility for metal atom binding to three L molecules simultaneously. Original Russian Text ? E.A. Goreshnik, M.G. Mys’kiv, 2008, published in Koordinatsionnaya Khimiya, 2008, Vol. 34, No. 11, pp. 826–830.  相似文献   

15.
New antimony(III) chloride complexes with heterocyclic thioamides, thiourea (TU), 2-mercapto-5-methyl-benzimidazole (MMBZIM), 3-methyl-2-mercaptobenzothiazole (MMBZT), 2-mercaptopyrimidine (PMT), 2-mercaptopyridine (PYT) of formulae [SbCl3(TU)2] (1), [SbCl3(MMBZIM)2] (2), [SbCl3(MMBZT)2] (3), [SbCl3(PMT)2] (4), [SbCl3(μ 2-S)(PYT)2] (5) were synthesized and characterized by elemental analysis, FT-IR and FT-Raman spectroscopies, and TG-DTA analysis. The crystal structure of 5 was also determined by X-ray diffraction. [C10H10Cl3N2S2Sb] (5) crystallizes in space group C2/c, with a?=?25.0169(10)?Å, b?=?9.7952(3)?Å, c?=?12.9329(5)?Å, β?=?109.702(4)°, and Z?=?8. Crystals of 5 grown from acetonitrile solutions adopt a square-pyramidal geometry. The equatorial plane is formed by three chlorides and one sulfur atom from the thione ligand while the second sulfur is axial. The complexes were evaluated for their biological activities and compared with [SbCl3(MMI)2] (6) (MMI?=?2-mercapto-1-methylimidazole) and other isostructural ones. The complexes showed moderate cytostatic activity against murine leukemia cells (L1210), murine mammary carcinoma cells (FM3A), human T-lymphocyte (Molt4/C8, CEM), and human cervix carcinoma (HeLa) cells. The chloro and iodo derivatives show better cytostatic activity than the bromo ones.  相似文献   

16.

A novel hybrid compound, [(CH3)2NH2]6[Cu(DMF)4(GeW12O40 4-)2] [sdot] 2DMF, has been synthesized from H4GeW12O40 [sdot] n H2O, CuCl2 and N, N -dimethylformamide (DMF) in aqueous solution and characterized by elemental analysis, UV and IR spectra. Single crystal X-ray structure analysis shows that the crystal consists of a α-Keggin heteropolyanion-supported anion [Cu(DMF)4(GeW12O40 4-)2], two free N, N-dimethylformamide molecules, six protonated dimethylamine (DMA) molecules, and that the coordinating atoms of DMF are the oxygen atoms of C=O group. Thermal analysis indicates that the thermal stability of the GeW12O40 4- anion in the title compound is stronger than that in acid.  相似文献   

17.
Two new salts of the cation [CuI(dmp)2]+ (dmp is 2,9‐dimeth­yl‐1,10‐phenanthroline, C14H12N2), namely bis­[bis­(2,9‐dimeth­yl‐1,10‐phenanthroline‐κ2N,N′)copper(I)] bis­(hexa­fluorophos­phate) hemi[bis­(4‐pyridylmethyl­idene)hydrazine] acetonitrile solvate, [Cu(C14H12N2)2]2(PF6)2·0.5C12H10N4·C2H3N or [Cu(dmp)2]2(PF6)2·0.5(bpmh)·CH3CN [bpmh is bis­(4‐pyridylmethyl­idene)hydrazine, C12H10N4], (I), and bis­(2,9‐dimeth­yl‐1,10‐phenanthroline‐κ2N,N′)copper(I) dicyanamide, [Cu(C14H12N2)2](C2N3) or [Cu(dmp)2][N(CN)2], (II), are reported. The Cu—N bond lengths and the distortion from idealized tetra­hedral geometry of the dmp ligands are discussed and compared with related compounds. The bpmh molecule in (I) is π–π stacked with a dmp ligand at a distance of 3.4 Å, rather than coordinated to the metal atom. The molecule lies across an inversion center in the crystal. In (II), the normally coordinated dicyanamide mol­ecule is present as an uncoordinated counter‐ion.  相似文献   

18.
The blue copper complex compounds [Cu(phen)2(C6H8O4)] · 4.5 H2O ( 1 ) and [(Cu2(phen)2Cl2)(C6H8O4)] · 4 H2O ( 2 ) were synthesized from CuCl2, 1,10‐phenanthroline (phen) and adipic acid in CH3OH/H2O solutions. [Cu(phen)2‐ (C6H8O4)] complexes and hydrogen bonded H2O molecules form the crystal structure of ( 1 ) (P1 (no. 2), a = 10.086(2) Å, b = 11.470(2) Å, c = 16.523(3) Å, α = 99.80(1)°, β = 115.13(1)°, γ = 115.13(1)°, V = 1617.5(5) Å3, Z = 2). The Cu atoms are square‐pyramidally coordinated by four N atoms of the phen ligands and one O atom of the adipate anion (d(Cu–O) = 1.989 Å, d(Cu–N) = 2.032–2.040 Å, axial d(Cu–N) = 2.235 Å). π‐π stacking interactions between phen ligands are responsible for the formation of supramolecular assemblies of [Cu(phen)2(C6H8O4)] complex molecules into 1 D chains along [111]. The crystal structure of ( 2 ) shows polymeric [(Cu2(phen)2Cl2)(C6H8O4)2/2] chains (P1 (no. 2), a = 7.013(1) Å, b = 10.376(1) Å, c = 11.372(3) Å, α = 73.64(1)°, β = 78.15(2)°, γ = 81.44(1)°, V = 773.5(2) Å3, Z = 1). The Cu atoms are fivefold coordinated by two Cl atoms, two N atoms of phen ligands and one O atom of the adipate anion, forming [CuCl2N2O] square pyramids with an axial Cl atom (d(Cu–O) = 1.958 Å, d(Cu–N) = 2.017–2.033 Å, d(Cu–Cl) = 2.281 Å; axial d(Cu–Cl) = 2.724 Å). Two square pyramids are condensed via the common Cl–Cl edge to centrosymmetric [Cu2Cl2N4O2] dimers, which are connected via the adipate anions to form the [(Cu2(phen)2Cl2)(C6H8O4)2/2] chains. The supramolecular 3 D network results from π‐π stacking interactions between the chains. H2O molecules are located in tunnels.  相似文献   

19.
采用新的方法合成了1-亚甲基苯并咪唑-1,4,7-三氮环壬烷配体, 利用该配体合成了一个新的铜配合物[Cu(C14H21N5)Br]2•[CuBr4] ([Cu(C14H21N5)Br]•[CuBr4]2-•[Cu(C14H21N5)Br]), 并测定了它的晶体结构, 结果表明: 该配合物的晶体属于单斜晶系的C2/c空间群, 晶胞参数a=1.96209(15) nm, b=0.82319(5) nm, c=2.39249(15) nm, α=90.00°, β=102.996(2)°, γ=90.00°, V=3.7653(4) nm3, Z=4, μ(Mo Kα)=8.083 mm-1, Dc=2.097 Mg/m3, F(000)=2308, R=0.0417, wR=0.0945, GOF=0.933. 该配合物由两个1-亚甲基苯并咪唑-1,4,7-三氮环壬烷一溴合铜配阳离子和一个四溴合铜配阴离子组成. 在两个配阳离子中, 每个Cu(II)离子与五个配位原子配位(四个氮原子和一个溴阴离子), 位于一个变形四方锥的中心. 在配阴离子中, Cu(II)离子与四个溴阴离子配位, 位于一个稍变形四面体的中心.  相似文献   

20.
Three new copper(II) complexes with isonicotinic acid N-oxide (HL) and 1,10-phenanthroline (phen) as ligands, [Cu(L)(phen)(H2O)]2(NO3)2···2H2O (1), [Cu(L)(phen)(H2O)]2(ClO4)2···2H2O (2), and [Cu(L)(phen)Br]2- [Cu(L)(phen)(H2O)]2Br2···6H2O (3) have been synthesized and structurally characterized. The structures of all three complexes feature a Cu2 dimer formed by two Cu(II) ions interconnected by two bridging ligands. Each copper(II) ion has a distorted square pyramidal coordination geometry with elongated axial coordination by an aqua ligand or halogen anion. The isonicotinic acid N-oxide anion is bidentate, being coordinated to two Cu(II) ions through its N-O oxygen and one of its carboxylate oxygen atoms. Magnetic susceptibility measurements show a Curie–Weiss paramagnetic behavior characteristic of one unpaired electron for a copper(II) ion for all three complexes.  相似文献   

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