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1.
N,N-bis(N-methyl-2-ylmethylbenzimidazole)aniline (EtAIDB) and its transition metal complexes, [Cu(EtAIDB)Br2]·EtOH {dibromo[N,N-bis(N-methyl-2-ylmethylbenzimidazole)aniline] copper(II) ethanol} (1) and [Zn(EtAIDB)Br2] {dibromo[N,N-bis(N-methyl-2-ylmethylbenzimidazole)aniline] zinc(II)} (2), have been synthesized and characterized by elemental analysis, molar conductivity, UV–visible, and IR spectroscopy. The X-ray crystallographic studies of 1 and 2 have shown two different arrangements: 1 is distorted square-based pyramidal, while 2 can be treated as distorted tetrahedral. The cyclic voltammogram of 1 represents quasi-reversible Cu2+/Cu+ pairs. In vitro antioxidant tests showed that 1 had significant antioxidant activity against superoxide and hydroxy radicals.  相似文献   

2.
Complex [Cu(tbt)Cl2]n (tbt = 1-tert-butyl-1H-tetrazole) was prepared by reaction of tbt with copper(II) chloride in solution. According to single-crystal X-ray analysis, this complex presents 1D coordination polymer, formed at the expense of double chlorido bridges between neighboring pentacoordinate copper(II) cations. 1-tert-Butyl-1H-tetrazole acts as monodentate ligand coordinated by CuII cations via the heteroring N4 atoms. The temperature-dependent magnetic susceptibility measurements of novel complex [Cu(tbt)Cl2]n as well as described previously 1D coordination polymer [Cu(tbt)2Cl2]n, and linear trinuclear complex [Cu3(tbt)6Br6], were carried out. Magnetic studies revealed that the copper(II) ions were weakly ferromagnetically coupled in polymeric copper(II) chloride complexes, whereas complex [Cu3(tbt)6Br6] showed antiferromagnetic coupling.  相似文献   

3.
1‐tert‐Butyl‐1H‐1,2,4‐triazole (tbtr) was found to react with copper(II) chloride or bromide to give the complexes [Cu(tbtr)2X2]n and [Cu(tbtr)4X2] (X = Cl, Br). 1‐tert‐Butyl‐1H‐tetrazole (tbtt) reacts with copper(II) bromide resulting in the formation of the complex [Cu3(tbtt)6Br6]. The obtained crystalline complexes as well as free ligand tbtr were characterized by elemental analysis, IR spectroscopy, thermal and X‐ray analyses. For free ligand tbtr, 1H NMR and 13C NMR spectra were also recorded. In all the complexes, tbtr and tbtt act as monodentate ligands coordinated by CuII cations via the heteroring N4 atoms. The triazole complexes [Cu(tbtr)2Cl2]n and [Cu(tbtr)2Br2]n are isotypic, being 1D coordination polymers, formed at the expense of single halide bridges between neighboring copper(II) cations. The isotypic complexes [Cu(tbtr)4Cl2] and [Cu(tbtr)4Br2] reveal mononuclear centrosymmetric structure, with octahedral coordination of CuII cations. The tetrazole compound [Cu3(tbtt)6Br6] is a linear trinuclear complex, in which neighboring copper(II) cations are linked by single bromide bridges.  相似文献   

4.
Abstract

In the present study, the oxidative dissolution of metallic copper has been explored with the intention to prepare some new complexes with urotropine (hmta) and triethylenediamine (dabco) ligands. All the compounds synthesized were characterized by single-crystal X-ray diffraction and Raman spectroscopy. Reactions performed in a DMSO/CuCl2?2H2O mixture resulted in [(μ-Cl)2CuI(hdabco+)CuI(μ-Cl)(κS-DMSO)]n and [CuICl(hmta)2] complexes. Their isostructural bromide analogs [(μ-Br)2CuI(hdabco+)CuI(μ-Br)(κS-DMSO)]n and [CuIBr(hmta)2] were prepared by the reaction of elemental copper with respective ligands in a DMSO/CBr4 mixture. Early interrupted reaction of the copper wire with the DMSO/CBr4/dabco solution resulted in an appearance of crystals of the [CuI2Br2(CO)2(dabco)]n carbonyl complex on the copper surface. It arises with the participation of in situ formed carbon monoxide. Despite the identical stoichiometry, the crystal structure of the [Cu2Br2(CO)2(dabco)]n complex is markedly different from that of a known [Cu2Cl2(CO)2(dabco)]n analog.  相似文献   

5.
C om m ent Levofloxacin (S-(-)9-fluoro-2,3-dihydro-3-m ethyl- 10-(4-m ethyl-1-piperazinyl)-7-oxo-7H -pyrido[1,2,3-de]- 1,4-benzoxaxin-6-carboxilic acid)(Leof),is a synthetic fluorinated quinolone derivative, having activity a- gainstboth Gram ( )and Gram …  相似文献   

6.
The Schiff N‐allylamine‐4‐(ethylenediamine‐5‐methylsalicylidene)‐1,8‐naphthalimide (H2L) and its copper(II) complex, [Cu(HL)2] · 0.5DMF, were synthesized and characterized. The crystal structure of the CuII complex reveals a slightly distorted square‐planar arrangement provided by two N and O donors from two deprotonated ligands. In addition, the DNA‐binding properties of the ligand and CuII complex were investigated by fluorescence spectra, electronic absorption, and viscosity measurements. The experimental studies of the DNA‐binding properties indicated that the ligand and CuII complex reacted with DNA via intercalation binding mode, and binding affinity for DNA takes the order: ligand > CuII complex. The antioxidant assay in vitro suggested that both exhibited potential intensely antioxidant properties, and the ligand is more effective than its CuII complex.  相似文献   

7.
An unexpected dinuclear Cu(II) complex, [Cu2(L2)2] (H2L2?=?3-methoxysalicylaldehyde O-(2-hydroxyethyl)oxime), has been synthesized via complexation of Cu(II) acetate monohydrate with H4L1. Catalysis by Cu(II) results in unexpected cleavage of two N–O bonds in H4L1, giving a dialkoxo-bridged dinuclear Cu(II) complex possessing a Cu–O–Cu–O four-membered ring core instead of the usual bis(salen)-type tetraoxime Cu3–N4O4 complex. Every complex links six other molecules into an infinite-layered supramolecular structure via 12 intermolecular C–H?···?O hydrogen bonds. Furthermore, Cu(II) complex exhibits purple emission with maximum emission wavelength λmax?=?417?nm when excited with 312?nm.  相似文献   

8.
An unexpected dinuclear Cu(II) complex, [Cu2(L2)2], has been synthesized via complexation of Cu(II) acetate monohydrate with a bis(Salamo) ligand H2L1. Catalysis of Cu(II) ions results in unexpected cleavage of two N–O bonds in H2L1, giving a dialkoxo-bridged dinuclear Cu(II) complex. Each Cu(II) complex possesses a Cu–O–Cu–O four-membered ring instead of the usual bis(Salamo) [Cu2L1] complex with H2L1. The H2L1 molecule is stabilized by intramolecular O1–H1?N1 hydrogen bonds and π?π stacking interactions linking adjacent molecules into a 1-D infinite zigzag chain. In the structure of the Cu(II) complex, intermolecular hydrogen bonds have stabilized the Cu(II) complex to form a self-assembling infinite 1-D linear chain. Furthermore, the H2L1 ligand shows intense photoluminescence with two emissions at ca. 370 and 464 nm upon excitation at 310 nm. The Cu(II) complex shows photoluminescence with maximum emission at ca. 423 nm upon excitation at 370 nm.  相似文献   

9.
One nonlinear and one linear trinuclear copper(II) complex [Cu3(dien)2(pdc)2CH3OH]2?·?6CH3OH (1) and [Cu3(pdc)2(CH3OH)6(H2O)4] (2) were prepared and characterized structurally, where dien is diethylenetriamine and pdc3? the trianion of 3,5-pyrazoledicarboxylic acid. Both complexes consist of 3,5-pyrazoledicarboxylato-bridged trinuclear copper(II) centers. In 1, copper(II) ions are five-coordinate in distorted square pyramids with bond angles 164.78° for Cu(1)–Cu(2)–Cu(3) and 164.51° for Cu(4)–Cu(5)–Cu(6). In 2, the three copper(II) ions are six-coordinate with elongated octahedral geometry. The trinuclear units of 1 and 2 interact through hydrogen bonds to form 3-D and 2-D supramolecular networks, respectively. Variable temperature magnetic susceptibility measurements show that 1 and 2 are antiferromagnetically coupled with J values of ?11.2 and ?13.3?cm?1.  相似文献   

10.
The complexes [Cu(dpp)Br2] ( 1 ) and [Cu(dpp)2][CuBr2] ( 2 ) (dpp = 2,9‐diphenyl‐1,10‐phenanthroline) were synthesized and characterized by single‐crystal X‐ray diffraction methods. Reaction of copper(II) bromide with the dpp ligand in dichloromethane at room temperature afforded 1 , which is a rare example of non‐square planar four‐coordinate copper(II) complexes. Complex 1 crystallizes in the monoclinic space group C2/c with a = 15.352(3), b = 13.192(3), c = 11.358(2) Å, β = 120.61(3)°, V = 1979.6(7) Å3, Z = 4, Dcalc = 1.865 g cm?3. The coordination geometry about the copper center is distorted about halfway between square planar and tetrahedral. The Cu‐N distance is 2.032(2) Å and the Cu‐Br distance 2.3521(5) Å. Heating a CH2Cl2 or acetone solution of 1 resulted in complex 2 , which consists of a slightly distorted tetrahedral [Cu(dpp)2]+ cation and a linear two‐coordinate [CuBr2]? anion. 2 crystallizes in the triclinic space group with a = 10.445(2), b = 11.009(2), c = 18.458(4) Å, α = 104.72(3), β = 94.71(3), γ = 103.50(3)°, V = 1973.3(7) Å3, Z = 2, Dcalc = 1.602 g cm?3. The four Cu(1)‐N distances are between 2.042(3) and 2.067(3) Å, the distance of Cu(2)‐Br(1) 2.2268(8) Å, and the disordered Cu(3)‐Br(2) distances are 2.139(7) and 2.237(4) Å, respectively. Complex 2 could also be prepared by directly reacting CuBr with dpp in CH2Cl2.  相似文献   

11.
A copper(II) complex based on a V-shaped ligand, 2,6-bis(2-benzimidazolyl)pyridine (bbp), has been synthesized and characterized by elemental analysis, molecular conductivity, 1H NMR, IR, UV-Vis spectra, and X-ray single-crystal diffraction. The crystal structure of [Cu(bbp)2](pic)2?·?2DMF (pic?=?picrate) shows copper is six-coordinate forming a distorted octahedron. The interaction between Cu(II) complex and DNA was investigated by spectrophotometric methods and viscosity measurement. The experimental results suggest that the Cu(II) complex binds to DNA via intercalation. Antioxidant assay in vitro also shows that the Cu(II) complex possesses significant antioxidant activities.  相似文献   

12.
Reaction of [Si(3,5‐Me2pz)4] ( 1 ) with [Cu(MeCN)4][BF4] ( 2 ) gave the mono‐ and dinuclear copper complexes [Cu2(FTp*)2] ( 3 ) and [Cu(FTp*)2] ( 4 ). Both complexes contain the so‐far unprecedented boron‐fluorinated FTp* ligand ([FB(3,5‐Me2pz)3]? with pz=pyrazolyl) originating from 1 , acting as a pyrazolyl transfer reagent, and the [BF4]? counter anion of 2 , serving as the source of the {BF} entity. The solid‐state structures as well as the NMR and EPR spectroscopic characteristics of the complexes were elaborated. Pulsed gradient spin echo (PGSE) experiments revealed that 3 retains (almost entirely) its dimeric structure in benzene, whereas dimer cleavage and formation of acetonitrile adducts, presumably [Cu(FTp*)(MeCN)], is observed in acetonitrile. The short Cu???Cu distance of 269.16 pm in the solid‐state is predicted by DFT calculations to be dictated by dispersion interactions between all atoms in the complex (the Cu?Cu dispersion contribution itself is only very small). As revealed by cyclic voltammetry studies, 3 shows an irreversible (almost quasi‐reversible at higher scan rates) oxidation process centred at Epa=?0.23 V (E01/2=?0.27 V) (vs. Fc/Fc+). Oxidation reactions on a preparative scale with one equivalent of the ferrocenium salt [Fc][BF4] (very slow reaction) or air (fast reaction) furnished blue crystals of the mononuclear copper(II) complex [Cu(FTp*)2] ( 4 ). As expected for a Jahn–Teller‐active system, the coordination sphere around copper(II) is strongly distorted towards a stretched octahedron, in accordance with EPR spectroscopic findings.  相似文献   

13.
Three new diclofenac‐based copper(II) complexes, namely tetrakis{μ‐2‐[2‐(2,6‐dichloroanilino)phenyl]acetato‐κ2O:O′}bis(methanol‐κO)copper(II), [Cu2(μ‐dicl)4(CH3OH)2] ( 1 ), bis{2‐[2‐(2,6‐dichloroanilino)phenyl]acetato‐κ2O,O′}bis(1‐vinyl‐1H‐imidazole‐κN3)copper(II), [Cu(dicl)2(vim)2] ( 2 ), and bis{2‐[2‐(2,6‐dichloroanilino)phenyl]acetato‐κ2O,O′}bis(1H‐imidazole‐κN3)copper(II), [Cu(dicl)2(im)2] ( 3 ) [dicl is diclofenac (C14H10Cl2NO2), vim is 1‐vinylimidazole (C5H6N2) and im is imidazole (C3H4N2)], have been synthesized and characterized by elemental analysis, FT–IR spectroscopy, thermal analysis and single‐crystal X‐ray diffraction. X‐ray diffraction analysis shows that complex 1 consists of dimeric units in which the dicl ligand exhibits a bidentate syn,syn‐μ2 coordination mode linking two copper(II) centres. Complexes 2 and 3 have mononuclear units with the general formula [Cu(dicl)2L2] (L is vim or im) in which the CuII ions are octahedrally coordinated by two L and two dicl chelating ligands. The L and dicl ligands both occupy the trans positions of the coordination octahedron. The different coordination modes of dicl in the title complexes were revealed by Fourier transform IR (FT–IR) spectroscopy. The spin matching between the copper(II) centres in the dimeric [Cu2(μ‐dicl)4(CH3OH)2] units was also confirmed by magnetic data to be lower than the spin‐only value and electron paramagnetic resonance (EPR) spectra. The thermal properties of the complexes were investigated by thermogravimetric (TG) and differential thermal analysis (DTA) techniques.  相似文献   

14.
A Schiff base bis(N-salicylidene)-3-oxapentane-1,5-diamine (H2L) and its Cu(II) complex, [Cu2(L)2]?CHCl3, have been synthesized and characterized by physicochemical and spectroscopic methods. Single-crystal X-ray analysis revealed that the complex is a centrosymmetric binuclear neutral entity, in which Cu(II) is a five-coordinate in a distorted trigonal bipyramidal geometry. The DNA-binding properties of the free ligand and the complex have been investigated by electronic absorption, fluorescence, and viscosity measurements. The results suggest that the H2L and the complex to DNA via the intercalation mode and the binding affinity of the complex were higher than that of the H2L. The intrinsic binding constants Kb of the ligand and the complex are 2.2 × 104 and 2.7 × 104 M?1, respectively. Antioxidant assay in vitro shows the Cu(II) complex possesses significant antioxidant activities and better scavenging activity than the H2L and other antioxidants.  相似文献   

15.
Methanol‐ and temperature‐induced dissolution–recrystallization structural transformation (DRST) was observed among two novel CuII complexes. This is first time that the combination of X‐ray crystallography, mass spectrometry and density functional theory (DFT) theoretical calculations has been used to describe the fragmentation and recombination of a mononuclear CuII complex at 60 °C in methanol to obtain a binuclear copper(II) complex. Combining time‐dependent high‐resolution electrospray mass spectrometry, we propose a possible mechanism for the conversion of bis(8‐methoxyquinoline‐κ2N,O)bis(thiocyanato‐κN)copper(II), [Cu(NCS)2(C10H9NO)2], Cu1 , to di‐μ‐methanolato‐κ4O:O‐bis[(8‐methoxyquinoline‐κ2N,O)(thiocyanato‐κN)copper(II)], [Cu2(CH3O)2(NCS)2(C10H9NO)2], Cu2 , viz. [Cu(SCN)2( L )2] ( Cu1 ) → [Cu( L )2] → [Cu( L )]/ L → [Cu2(CH3O)2(NCS)2( L )2] ( Cu2 ). We screened the antitumour activities of L (8‐methoxyquinoline), Cu1 and Cu2 and found that the antiproliferative effect of Cu2 on some tumour cells was much greater than that of L and Cu1 .  相似文献   

16.
A dinuclear copper(II) complex, [CuII2(L)2] is afforded by the reaction of CuCl2 · 2H2O with a triazenido ligand, 1-[(2-carboxymethyl) benzene]-3-[2-carboxybenzene] triazene (H2L). Structural investigation shows that the copper-copper distance [2.3985(7) Å] is significantly shorter than the sum of the van der Waals radii of Cu (1.40 Å), suggesting that there are metal-metal bonds in [CuII2(L)2]. In solid, there is a strong antiferromagnetic interaction between copper(II) ions (J = –135.6 cm–1). In homogeneous environment, [CuII2(L)2] shows electrocatalytic activities for hydrogen generation both from acetic acid with a turnover frequency (TOF) of 32 mol of hydrogen per mole of catalyst per hour [mol(H2) · mol–1(catalyst) · h–1] at an overpotential (OP) of 941.6 mV, and neutral buffer with a TOF of 512 mol(H2) · mol–1(catalyst) · h–1 at an OP of 836.7 mV.  相似文献   

17.
One μ‐alkoxo‐μ‐carboxylato bridged dinuclear copper(II) complex, [Cu2(L1)(μ‐C6H5CO2)] ( 1 )(H3L1 = 1,3‐bis(salicylideneamino)‐2‐propanol)), and two μ‐alkoxo‐μ‐dicarboxylato doubly‐bridged tetranuclear copper(II) complexes, [Cu4(L1)2(μ‐C8H10O4)(DMF)2]·H2O ( 2 ) and [Cu4(L2)2(μ‐C5H6O4]·2H2O·2CH3CN ( 3 ) (H3L2 = 1,3‐bis(5‐bromo‐salicylideneamino)‐2‐propanol)) have been prepared and characterized. The single crystal X‐ray analysis shows that the structure of complex 1 is dimeric with two adjacent copper(II) atoms bridged by μ‐alkoxo‐μ‐carboxylato ligands where the Cu···Cu distances and Cu‐O(alkoxo)‐Cu angles are 3.5 11 Å and 132.8°, respectively. Complexes 2 and 3 consist of a μ‐alkoxo‐μ‐dicarboxylato doubly‐bridged tetranuclear Cu(II) complex with mean Cu‐Cu distances and Cu‐O‐Cu angles of 3.092 Å and 104.2° for 2 and 3.486 Å and 129.9° for 3 , respectively. Magnetic measurements reveal that 1 is strong antiferromagnetically coupled with 2J =‐210 cm?1 while 2 and 3 exhibit ferromagnetic coupling with 2J = 126 cm?1 and 82 cm?1 (averaged), respectively. The 2J values of 1–3 are correlated to dihedral angles and the Cu‐O‐Cu angles. Dependence of the pH at 25 °C on the reaction rate of oxidation of 3,5‐di‐tert‐butylcatechol (3,5‐DTBC) to the corresponding quinone (3,5‐DTBQ) catalyzed by 1–3 was studied. Complexes 1–3 exhibit catecholase‐like active at above pH 8 and 25 °C for oxidation of 3,5‐di‐tert‐butylcatechol.  相似文献   

18.
A 1-D polymeric copper(II) complex alternately bridged by N,N′-bis(N-hydroxyethylaminopropyl)oxamide (heap2?) and terephthalate (tpa2?), [Cu2(heap)(tpa)] n , has been synthesized and characterized by single-crystal X-ray diffraction. The crystal structure reveals that the asymmetric unit of the copper(II) polymer is half a dinuclear copper(II) complex, [Cu2(heap)(tpa)], in which Cu(II) is located in a square-pyramidal coordination environment. Separations of Cu(II) through heap2? and tpa2? bridges are 5.2459(6) and 11.1375(6)?Å, respectively. The complex chains, accompanied with glide planes parallel to the a0c plane, can be classified to two groups according to their extending direction. Hydrogen bonds occur between a complex chain and any adjacent ones in the other orientation. Consequently, a 3-D supramolecular network is completed. The polymeric copper(II) complex exhibits potent anticancer activities against human hepatocellular carcinoma cell SMMC-7721 and human lung adenocarcinoma cell A549 tested by sulforhodamine B assays. The interactions of the polymeric copper(II) complex with herring sperm DNA (HS-DNA) are investigated by using electronic absorption titration, fluorescence titration, electrochemical titration, and viscometry measurements. The results suggest that the polymeric copper(II) complex interacts with HS-DNA via intercalation with intrinsic binding constant of 1.8?×?106?(mol?L?1)?1.  相似文献   

19.
陈三平  范广  高胜利 《中国化学》2008,26(2):286-289
以1,2-反式-二(4-吡啶基)乙烯桥连卤化铜分别得到配合物[Cu2(bpe)Cl 2] n (1), [Cu2(bpe)Br2] n (2) 和 [Cu2(bpe)I2] n (3)。通过X-射线单晶衍射法对配合物1的结构进行了研究,晶体学数据:单斜晶系, P 2(1)/c空间群, a = 0.3788(8) nm, b = 1.5059(3) nm, c = 1.0875(2)nm, β = 96.262(4) °, V = 616.5(2)Å3, Z = 2, S = 1.002,最终残差因子( I >2 σ ( I )) R 1 = 0.0288, wR 2 = 0.0579,对于全部数据 R 1 = 0.0509, wR 2 = 0.0615。元素分析及红外光谱分析表明,该类配合物为同晶化合物。另外,通过热重分析对配合物的热稳定性进行了研究。  相似文献   

20.
Four Cu(I) complexes with 1-(2-hydroxyethyl)-5-mercapto-1H-tetrazole (Hhmt) as a ligand, [Cu(hmt)]n (1), [Cu2Cl(hmt)]n (2), [Cu4Br(hmt)3]n (3), and [Cu4I(hmt)3]n (4), have been synthesized. In 14, hmt adopts a μ4-η1?:? η1?:? ηS2 coordinate mode to join the adjacent Cu(I) ions, which form different two-dimensional (2-D) structures. In 1, the neighboring four Cu(I) atoms are connected by μ4-hmt to form a 2-D structure. In 2, the Cu(I) ions are firstly connected with Cl ions to form a 1-D [Cu4Cl2] subunit chain, which then have been bridged by hmt to form a 2-D structure. However, the inorganic [Cu4Br] and [Cu4I] motifs are respectively connected by hmt to form 2-D structures in isostructural 3 and 4. In addition, the fluorescent properties and the thermal stability properties of 14 have been investigated.  相似文献   

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