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1.
The kinetics of the ligand exchange reaction of the Cu(II)-ammine complex with poly(vinyl alcohol) (PVA) has been studied by a stopped-flow method at pH 9–10, at μ=0.1 (NH4Cl) and at 25°C. The reaction is initiated by the formation of unstable [Cu(NH3)3]2+ by the attack of H+ on Cu(II)-ammine complex, and proceeds through the mixed complex {[Cu(NH3)3(O?PVA)]2+}. This step may be rate-determining, followed by a rapid reaction. Finally, the Cu(II) ion is taken up by PVA. The rate is given by d[Cu(II)?PVA]/dt=k[H+]{[Cu(NH3)4]2+}[PVA]/[NH4Cl], where k=k1 + k2[H+], k1=4.25× 10s?1 and k2=5.20× 1011l mol?1s?1.  相似文献   

2.
A novel Sm(III)–hyperbranched poly(ester‐amide) complex (Sm(III)–HBPEA) was synthesized, and characterized using Fourier transform infrared, 13C NMR and fluorescence spectroscopy and thermogravimetric analysis. Under the conditions used, HBPEA chelates to Sm3+ ions mainly via oxygen and nitrogen atoms of functional groups on the HBPEA chain. Modes of bonding of carboxyl groups, terminal hydroxyl groups and amide carbonyl structures may play the most important role in the coordination interaction. On excitation with UV light, the complex exhibits characteristic emission of both HBPEA and Sm3+. The presence of Sm3+ ions slightly accelerates HBPEA decomposition. Copyright © 2010 Society of Chemical Industry  相似文献   

3.
Novel dinuclear copper(II) complex and phenoxy-bridged tetranuclear zinc(II) complex with 1,3-diphenyl-4-(salicylidene hydrazone)-phenylethylene-pyrazolone-5 (DPPeP-SAH) have been synthesized and characterized by X-ray crystallography. The X-ray diffraction analyses of the complexes show that two Cu(II) centers are bonded with two tetradentated ligands and the geometries around the central ions are slightly distorted square planar, while in zinc(II) complex central metal ions are held together by four μ-phenoxo bridges that lead to the formation of the tetra-μ-phenolatotetrazinc(II) centers.  相似文献   

4.
A novel compound [Ni(L)(H2O)2]0.5[Ni(L)(WO4)2]0.5·4H2O (1) (L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.18,07.12]docosane) has been structurally and magnetically characterized. The nickel(II) ions are shown to be in distorted octahedral environments with secondary amines of macrocycles in which two trans water molecules and two trans tungstate ions are assembled around each metal center. Two nickel(II) complexes are connected into a one-dimensional chain via hydrogen bonds. The magnetic susceptibility measurement for 1 indicates weak antiferromagnetic interaction (J=−1.01(2) cm−1; H=−JΣSi·Si+1) between the S=1 nickel(II) paramagnetic centers.  相似文献   

5.
Two new mixed ligand complexes of copper(II) with acetylacetonate (acac) and 2,2′-bipyridine (bpy) belonging to the class of cytotoxic and antineoplastic compounds known as CASIOPEINAS® have been synthesized and characterized on the basis of analytical and spectroscopic data. Molecular structures of the complexes, [Cu(acac)(bpy)Cl][Cu(acac)(bpy)(H2O]Cl.H2O and [Cu(acac)(bpy)Br]H2O, were established by single crystal X-ray study. The Cu(II) ion in both the complexes exhibited square pyramidal geometry with acac and bpy in the equatorial plane and halide/water in the axial position. Interestingly, for the complex with chloride anion, two types of complexes with chloride and water at the axial positions were derived from the same reaction and co-crystallized in the asymmetric unit with strong intermolecular interactions. Microbial property of these two complexes as antibacterial and antifungal agents has been investigated and some of the results are comparable to that of the standard drugs such as E. coli, P. aeruginosa, S. aureus, S. pyogenes, A. niger and C. albicans, used in this study.  相似文献   

6.
新型salamo衍生物苦味酸铜(Ⅱ)配合物的合成与表征   总被引:3,自引:0,他引:3  
以丙酮为溶剂,1,3-二胺氧丙烷双缩邻香草醛(H2L)与苦味酸铜反应,制备了一种新型salamo衍生物苦味酸铜(Ⅱ)配合物,其结构经元素分析,1HNMR,IR,TG-DTA及UV表征。结果表明,新型salamo衍生物是一种四齿配体,配合物的可能结构式为[Cu4L2(pic)4(H2O)2].2CH3COCH3.2H2O。  相似文献   

7.
One novel hexapodal ligand 1,2,3,4,5,6-hexakis[(4,5-diazafluoren-9-yliminoxy)methyl]benzene (L) and corresponding Ru(II) polypyridyl complex [(bpy)12(RuII)6L](PF6)12 have been synthesized. Spectroscopic properties of the complex are investigated by UV–Vis absorption and fluorescence spectrometry. The complex shows metal-to-ligand charge transfer absorption at 438 nm and emission at 579 nm. Cyclic voltammetry of the complex comprises one Ru(II)-centered quasi-reversible oxidation at 1.31 V and three ligand-centered reductions.  相似文献   

8.
Two copper(II)–poly(pyrazolyl)methane complexes [Cu2(bpm)4(ta)](ClO4) 2 · 2H2O 1 and {[Cu2(tpm)2(ta)2] · H2O}n 2 (bpm = bis(3,5-dimethylpyrazolyl)methane, tpm = tris(pyrazolyl)methane, H2ta = terephthalic acid) were synthesized and characterized by elemental analysis, FT-IR and UV–vis spectra. 1 is a binuclear complex, while 2 exhibits as a 1D zigzag coordination polymer.  相似文献   

9.
An unusual copper(II) complex [Cu(L1a)2Cl2] CH3OH·H2O·H3O+Cl (1a) was isolated from a solution of a novel tricopper(II) complex [Cu3(HL1)Cl2]Cl3·2H2O (1) in methanol, where L1a is 3-(2-pyridyl)triazolo[1,5-a]-pyridine, and characterized with single crystal X-ray diffraction study. The tricopper(II) complex of potential ligand 1,5-bis(di-2-pyridyl ketone) carbohydrazone (H2L1) was synthesized and physico-chemically characterized, while the formation of the complex 1a was followed by time-dependant monitoring of the UV–visible spectra, which reveals degradation of ligand backbone as intensity loss of bands corresponding to O → Cu(II) charge transfer.  相似文献   

10.
以二甲基乙酰胺为溶剂,叔胺为盐酸吸收剂,将4,4′-二氨基二苯醚与2,6-二(4-氯甲酰苯氧基)苯甲腈进行低温缩聚反应,合成含氰侧基及醚基结构的聚芳酰胺。结果表明:当反应体系摩尔浓度为0.45~0.55mol/L,初始反应温度为0℃,以2-甲基吡啶为盐酸吸收剂时,制得的聚芳酰胺相对分子质量较高,该聚合物热分解温度(失重5%)为419℃。  相似文献   

11.
A new binuclear Cu(II) complex with an (E)-4-(2,4-diisopropylphenyl)-4-oxo-2-butenoato ligand (L) was successfully synthesized and characterized by elemental analysis and IR-spectroscopy. The structures of (E)-4-(2,4-diisopropylphenyl)-4-oxo-2-butenoic acid (HL), and the corresponding (tetrakis)-μ-[(E)-4-(2,4-diisopropylphenyl)-4-oxo-2-butenoato]-bis(ethanol)-copper(II) complex, [Cu2L4(C2H5OH)2], were determined by single crystal X-ray analyses and are preliminarily discussed. This is the first complex of a transition metal with ligand L, as well as the first determined crystal structure of a metal complex with this type of ligand. Analysis of the magnetic susceptibility measurements of the isolated [Cu2L4(C2H5OH)2] · H2O complex shows the existence of a strong anti-ferromagnetic intradimer coupling, with an exchange integral value 2J of −260 cm−1.  相似文献   

12.
A novel ytterbium (II) complex 2 supporting by a bridged bisphenolate ligand H2LOC4H7 (L = C4H7OCH2N(CH2‐2‐OC6H2‐3,5‐Bu)2) with a tetrahydrofuran donor on side‐arm was synthesized in high yield and characterized by elementary analysis, IR, 1H‐NMR, and 13C‐NMR. Ring‐opening polymerization of 1,3‐trimethylenecarbonate (TMC) was carried out using complex 2 and a known complex [Me2NCH2CH2N(CH2‐2‐O‐3,5‐C6H2(But)2)2]Yb 1 as the initiators, respectively. It was found that both complexes 1 and 2 can alone initiate the ring‐opening polymerization of TMC, and complex 1 showed higher activity than complex 2 . The activity of both complexes 1 and 2 was found to be higher than that of monodentate phenoxo ytterbium (II) complex (2,6‐Bu‐C6H3O)2Yb(THF)3. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

13.
We synthesized a new class of cyclometallated ruthenium(II) complexes, Ru(tctpy)(C^N)(NCS) (1, 2), where C^N is a bidentate cyclometallating ligand such as 2-phenylpyridinato or 2-(4-(2-phenylethynyl)phenyl)pyridinato. Although these complexes exist as stereoisomers, the microwave synthetic technique yielded only one isomer. These compounds act as light sensitizers and have excellent light-harvesting properties, especially in the near-IR region. Therefore, they can be used in dye-sensitized solar cells (DSCs). A DSC sensitized with 2 shows a 10% incident photon-to-current conversion efficiency at 900 nm.  相似文献   

14.
Nitric oxide (NO) is a well known potent antiplatelet agent, and its continuous release will effectively prevent the adhesion of platelets on artificial blood vessel walls. In this paper, polycarbonateurethane (PCU) with lipophilic Cu(II)‐complex (Cu(II)‐DTTCT) blending films were prepared and used as catalyst to generate NO from nitrite. The mechanical properties of PCU films blended with Cu(II)‐DTTCT were characterized by tensile strength measurement. The tensile stress and Young's modulus of PCU films blending with Cu(II)‐DTTCT increased, however, the elongation at break decreased compared with corresponding PCU films. The NO generation was investigated in vitro in the presence of NaNO2 and ascorbic acid in PBS (pH = 7.4) at 37°C. The flux of NO generation was quantitatively measured by Griess assay. NO flux and velocity increased with the increase of NaNO2 concentration, the concentration of ascorbic acid in PBS and the amount of Cu(II) in the films. The loss of Cu(II) from blending film surfaces was found during the in vitro NO generation experiments, which resulted in the decrease of NO flux in the second run. The PCU film could catalyze continually generation of NO for two days, which will provide a promising approach that enable endogenous NO generation on the surface of the medical devices. The generation of biologically active level of NO at the blood/polymer interface can reduce the risk of thrombosis on the implants. Polycarbonateurethane films with NO generation function may be used as high thromboresistant blood contacting materials or coating. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

15.
A new family of biodegradable amino‐acid‐based poly(ester amide)s (AA–PEAs) and amino‐acid‐based poly(ether ester amide)s (AA–PEEAs) consisting of reactive pendant functional groups (? COOH or ? NH2) were synthesized from unsaturated AA–PEAs and AA–PEEAs via a thiol–ene reaction in the presence of a radical initiator (2,2′‐azobisisobutyronitrile). The synthetic method was a one‐step reaction with near 100% yields under mild reaction conditions. The resulting functional AA–PEA and AA–PEEA polymers were characterized by Fourier transform infrared spectroscopy, NMR, and differential scanning calorimetry. These new functional AA–PEA and AA–PEEA derivatives had lower glass‐transition temperatures than the original unsaturated AA–PEA and AA–PEEA polymers, and their solubility in some organic solvents also improved. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

16.
Palladium(II) and platinum(II) anchored to 2- and 4-vinylpyridine polymers of different molecular weights were used for the dihydrogen reduction of various nitroaromatics and benzaldehyde in ethanol at 50°C. Palladium(II) complexes were far more effective than their platinum(II) analogues and the activity decreased with increasing molecular weights of the polymers. The nitroaromatics were selectively and almost completely reduced to the corresponding anilines. During reduction, the orange palladium(II) complexes changed to voluminous green precipitates, which could be used repeatedly and preserved for a long time without any loss of activity. A rate equation of the type: rate = K[Cat] [H2] has been derived and a reduction mechanism has been proposed on the basis of experimental results and kinetic data.  相似文献   

17.
Novel nickel(II) hexaaza macrocyclic complexes, [Ni(LR,R)](ClO4)2 (1) and [Ni(LS,S)](ClO4)2 (2), containing chiral pendant groups have been synthesized by an efficient one-pot template condensation and characterized (LR,R/S,S = 1,8-di((R/S)-α-methylbenzyl)-1,3,6,8,10,13-hexaazacyclotetradecane). The crystal structures of 1 and 2 were determined by single-crystal X-ray analysis. Each complex has a square-planar coordination environment for the nickel(II) ion, and is either an R or an S enantiomorph depending on the pendant groups. The circular dichroism spectrum of 1 showed a negative, positive and negative peak at 345, 440, and 492 nm, respectively, and that of 2 exhibited an enantiomeric pattern.  相似文献   

18.
Electron transfer mechanism during redox process of Pt(LSB)2, a derivative of S-benzyl-N-(ferrocenyl-1-methyl-metylidene)-dithiocarbazate (HLSB), is studied by cyclic voltammetry, differential pulse voltammetry, digitally simulation and in situ FTIR spectroelectrochemistry. Electrochemistry results indicated the redox process of Pt(LSB)2 involves two consecutive one-electron steps. Coordination of Pt to HLSB resulted in the increase of electron-withdrawing of the dithiocarbazate group, which is demonstrated by the positive shift of redox potentials of Pt(LSB)2 compared with those of HLSB. The peak-peak separation of 129 mV revealed a strong degree of electronic communication between the two-ferrocene moieties in Pt(LSB)2. The results of in situ FTIR indicated that electronic communication takes place through the skeleton chain of HLSB due to the extensive electron delocalization in the whole molecule.  相似文献   

19.
The reaction of [Ni(L)]Cl2·2H2O (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo [14,4,01.18,07.12]docosane) with trans-1,2-cyclopentanedicarboxylic acid (H2-cpdc) yields a 1D hydrogen-bonded infinite chain with formula [Ni(L)(H-cpdc)2] (1). This complex has been characterized by X-ray crystallography, spectroscopy and cyclic voltammetry. The crystal structure of 1 exhibits a distorted octahedral geometry about Ni atom with four nitrogen atoms of the macrocycle and two oxygen atoms of the H-cpdc ligand at the axial position. Compound 1 crystallizes in the monoclinic system P21/c with a = 8.7429(17), b = 10.488(2), c = 18.929(4) Å, β = 91.82(2), V = 1734.8(6) Å3, Z = 2. Electronic spectrum of 1 reveals a high-spin octahedral environment. Cyclic voltammetry of 1 undergoes two waves of a one-electron transfer corresponding to NiII/NiIII and NiII/NiI processes.  相似文献   

20.
E. Duñach 《Electrochimica acta》2008,53(13):4470-4477
An improved procedure has been developed using a catalytic amount of a nickel(II) complex in the efficient and selective electrochemical cyclization of propargyloxy and allyloxy bromo derivatives into substituted tetrahydrofurans using ethanol and ethanol-water mixtures as environmental-friendly systems. The reduction of the substrates proceeded via one-electron cleavage of the carbon-bromine bond to form a radical-type intermediate that undergoes cyclization to afford the tetrahydrofuran structures in good yields.  相似文献   

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