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1.
Cobaltocenium carboxylate is an unusual betaine that functions as a formally neutral carboxylate ligand with late transition metal centers comprising Co2+, Ni2+, Cu2+, Ag+, Zn2+, Cd2+, Hg2+, and Rh+. Structurally, a rich coordination chemistry is observed – from simple monomeric homoleptic complexes to heteroleptic dimeric, trimeric, and polymeric compounds, as shown by X‐ray diffraction of 11 compounds. Chemically, thermal decarboxylation was investigated aiming at the formation of cobaltocenium‐carbene transition metal complexes, in analogy to such chemistry of imidazolium carboxylate betaines. Cytotoxicity studies of cobaltocenium carboxylate transition metal complexes were performed to evaluate the medicinal bioorganometallic potential of these compounds. While cobaltocenium carboxylate was inactive, its complexes with Ag+, Cd2+, and Hg2+ triggered significant cytotoxic effects.  相似文献   

2.
The complexation reaction of dibenzopyridino-18-crown-6 (DBPY 18C6) with Co2+, Cu2+, Zn2+, Pb2+, Cd2+, Hg2+, and Ag+ have been studied in DMSO at 25°C by the spectrophotometric method. Murexide was used as a competitive colored ligand. The stoichiometry of metal ion-murexide and metal ions with DBPY18C6 complexes were estimated by mole ratio and continuous variation methods and emphasized by the KINFIT program. The stoichiometry of all the complexes was found to be 1: 1 (metal ion/ligand). The order of stability constants for the obtained metal ion-murexide complexes (1: 1) varies in the order Cu2+ > Cd2+ > Co2+ ∼ Pb2+ > Zn2+ > Ag+ > Hg2+. This trend shows that the transition metal ions clearly obey the Irving-Williams role. For the post-transition metal ions, the ionic radius and soft-hard behavior was the major affects in varying of this order. The dibenzopyridino-18-crown-6 complexes with the used metal ions vary as Ag+ > Pb2+ > Cu2+ > Cd2+ > Hg2+ > Zn2+ > Co2+. The article is published in the original.  相似文献   

3.
A new bipyridyl derivative 1 bearing rhodamine B as visible fluorophore was designed, synthesized and characterized as a fluorescent and colorimetric sensor for metal ions. Interaction with Cu2+, Zn2+, Cd2+, Hg+, and Hg2+ ions was followed by UV/Vis and emission spectroscopy. Upon addition of these metal ions, different colorimetric and fluorescent responses were observed. “Off-on-off” (Cu2+, Zn2+, and Hg2+) and “off-on” (Hg+ and Cd2+) systems were obtained. Probe 1 was explored to mimic XOR and OR logic operations for the simultaneous detection of Hg+–Cu2+ and Hg+–Zn2+ pairs, respectively. DFT calculations were also performed to gain insight into the lowest-energy gas-phase conformation of free receptor 1 as well as the atomistic details of the coordination modes of the various metal ions.  相似文献   

4.
A new 14-membered crown ether with nitrogen–sulfur donor atom carrying two anthryl groups was designed and synthesized by the reaction of the corresponding macrocyclic compound and 9-(chloromethyl) anthracene. The influence of metal cations such as Al3+, Zn2+, Fe2+, Fe3+, Co2+, Ni2+, Mn2+, Cu2+, Cd2+, Hg2+ and Pb2+ on the spectroscopic properties of the ligand was investigated in acetonitrile–dioxane solution (1/1) by means of absorption and emission spectrometry. The results of spectrophotometric titration experiments disclosed the complexation stoichiometry and complex stability constant of the novel ligand with Fe2+, Fe3+, Al3+, Cd2+, Cu2+, Zn2+, Pb2+ and Hg2+ cations. Absorption spectra show isobestic points in the spectrophotometric titration of these cations. The presence of excess of Al3+, Zn2+, Fe2+, Fe3+, Co2+, Ni2+, Mn2+, Cu2+, Cd2+, Hg2+ and Pb2+ cations caused an enhancement of anthryl fluorescence. Especially, the enhancement in case of the interaction of Hg2+ and Al3+ cations with the ligand was pronounced.  相似文献   

5.
A new crown ether carrying two anthryl groups with nitrogen–sulfur donor atom was designed and synthesized by the reaction of the corresponding macrocyclic compound and 9-chloromethyl anthracene. The influence of metal cations such as Al3+, Zn2+, Fe2+, Fe3+, Co2+, Ni2+, Mn2+, Cu2+, Cd2+, Hg2+ and Pb2+ on the spectroscopic properties of the ligand was investigated in acetonitrile–tetrahydofuran solution (1/1) by means of absorption and emission spectrometry. Absorption spectra show isosbestic points in the spectrophotometric titration of Fe2+, Fe3+, Al3+, Cu2+ and Hg2+. The results of spectrophotometric titration experiments disclosed the complexation stoichiometry and complex stability constant of the novel ligand with Fe2+, Fe3+, Al3+, Cu2+and Hg2+cations. The presence of excess amounts of Al3+, Zn2+, Fe2+, Fe3+, Co2+, Ni2+, Mn2+, Cu2+, Cd2+, Hg2+ and Pb2+ cations caused an enhancement of anthryl fluorescence. The ligand showed good sensitivity for Zn2+ with respect to other metal cations with linear range and detection limit of 1.4 × 10?7 to 4.1 × 10?6 M and 1.0 × 10?8 M respectively.  相似文献   

6.
Hui Xu  Xiwen Zeng  Huiling Dai 《中国化学》2011,29(10):2165-2168
A new fluorescent chemosensor based upon 1,8‐naphthalimide and 8‐hydroxyquinoline was synthesized, and its fluorescent properties in the presence of different metal cations (Hg2+, Ag+, Zn2+, Fe2+, Cd2+, Pb2+, Ca2+, Cu2+, Mg2+, and Ba2+) were investigated. It displayed fluorescence quenching with some heavy and transition metal (HTM) ions, and the quenching strongly depended on the nature of HTM ions.  相似文献   

7.
Here, we report an experimental study of the effect of toxic metal ions on photosensitized singlet oxygen generation for photodegradation of PAH derivatives, Anthracene‐9,10‐dipropionic acid disodium salt (ADPA) and 1,5‐dihydroxynapthalene (DHN) and photoinactivation of Escherichia coli bacteria by using cationic meso‐tetra(N‐methyl‐4‐pyridyl)porphine tetrachloride (TMPyP) as a singlet oxygen photosensitizer. Three s‐block metals ions, such as Na+, K+ and Ca2+ and five toxic metals such as Cd2+, Cu2+, Hg2+, Zn2+ and Pb2+ were studied. The s‐block metal ions showed no change in the rate of photodegradation of ADPA or DHN by TMPyP, whereas a dramatic change in the photodegradation of ADPA and DHN was observed in the presence of toxic metals. The maximum photodegradation rate constants of ADPA and DHN were observed for Cd2+ ions [(3.91 ± 0.20) × 10?3 s?1 and (7.18 ± 0.35) × 10?4 s?1, respectively]. Strikingly, the photodegradation of ADPA and DHN was almost completely inhibited in the presence of Hg2+ ions and Cu2+ ions. A complete inhibition of growth of E. coli was observed upon visible light irradiation of E. coli solutions with TMPyP and toxic metal ions particularly, Cd2+, Hg2+, Zn2+ and Pb2+ ions, except for Cu2+ ions where a significantly slow inhibition of E. coli's growth was observed.  相似文献   

8.
《Analytical letters》2012,45(17):3074-3087
Abstract

Insoluble porous solid, macrocyclic 22-membered ring, 1-oxa-6,9,12,15,18-pentaaza-2,22-disilacyclododocosane polysiloxane ligand system has been prepared by the reaction of a macro-silane agent with tetraethylorthosilicate. The macro-silane agent was prepared by the reaction of imino-bis(N-2-aminoethylacetamide) ligand with 3-iodopropyltrimethoxysilane in 1:3 molar ratio. The new prepared polysiloxane system exhibits variable potentials for the extraction of metal ions (Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Ag+, Cd2+, Hg2+, and Pb2+) from aqueous solutions. The ligand system shows high capacity to extract silver, lead, and mercury. Chemisorption of the metal ions by the ligand system at the optimum conditions was found in the order Ag + > Pb2+ > Hg2+ > Cu2+ > Ni2+ > Fe3+ > Co2+ > Cd2+ > Zn2+.  相似文献   

9.
A conjugated polymer was synthesized by the polymerization of 4,7‐dibromobenzo[2,1,3]thiadiazole ( M‐1 ) with tri{1,4‐diethynyl‐2,5‐bis(2‐(2‐methoxyethoxy)‐ethoxy)}‐benzene ( M‐2 ) via Pd‐catalyzed Sonogashira reaction. The polymer shows strong orange fluorescence. The responsive optical properties of the polymer on various metal ions were investigated through photoluminescence and UV–vis absorption measurements. The polymer displays highly sensitive and selective on‐off Hg2+ fluorescence quenching property in tetrahydrofuran solution in comparison with the other cations including Mg2+, Zn2+, Co2+, Ni2+, Cu2+, Ag+, Cd2+, and Pb2+. More importantly, the fluorescent color of the polymer sensor disappears after addition of Hg2+, which could be easily detected by naked eyes. The results indicate that this kind of polymer sensor incorporating benzo[2,1,3]thiadiazole moiety as a ligand can be used as a novel colorimetric and fluorometric sensor for Hg2+ detection. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

10.
Complexes of orotic acid with transition metals (Cu2+, Mn2+, VO2+, Zn2+, Hg2+, Cd2+, Fe3+, Cr3+, and Ag+) have been prepared and characterized by elemental, conductivity, magnetic measurements, i.r., n.m.r. and diffuse reflectance spectra. The ligand, in its monoanion form, coordinates through the carboxylic group to the metal. The Co2+ complex was also isolated under alkaline conditions and studied.  相似文献   

11.
In the present work, we have reported the synthesis of benzimidazoles functionalized crown ether derivatives of 4-formyl benzo-15-crown-5/4,4′-diformyl dibenzo-15-crown-5 and substituted diamine pyridine using sulfamic acid as a catalyst in DMSO. These molecules are used for the colorimetric determination of Au3+ selectively among other metal cations such as Fe2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Pb2+, Hg2+, Au3+ and Ag+ ions.  相似文献   

12.
In the framework of the development of bioassay, a procedure was developed for studying the combined effects of heavy metal ions on bacteria. The bacterium Bacillus subtilis niger was proposed as an analytical indicator. A universal calculation system was developed that allows one to obtain and analyze functional models of toxicity and the combined effects of toxicants. Models for the action of Zn2+–Cu2+, Zn2+–Cd2+, Zn2+–Cu2+–Cd2+, and Zn2+–Cu2+–Cd2+–Hg2+ mixtures on Bacillus subtilis niger were obtained and studied, and are discussed for the first time. The effect of the type of the nutrient medium on the character and structure of the combined effects was studied. The resulting models were applied to the determination of concentrations of heavy metal ions in mixtures.  相似文献   

13.
Zusammenfassung Die Trennung und Isolierung von folgenden Schwermetallen bei einem hohen Überschuß an Fremdionen mit Hilfe neuer selektiver Chelataustauscher wird beschrieben: Cu2+/Zn2+, Cu2+/Pb2+, Ag+/Cu2+, Ag+/Pb2+, Hg2+/Zn2+, Hg2+/Cd2+; Abtrennung von Hg2+. Unter gleichen Bedingungen war mit dem handelsüblichen Austauscher Dowex A-1 keine Trennung möglich.
Quantitative separation of heavy metals by means of chelating exchangers based on polystyrol
Summary The separation and isolation of the following heavy metals in presence of a high excess of foreign ions by means of new selective chelating exchangers is described: Cu2+/Zn2+, Cu2+/Pb2+, Ag+/Cu2+, Ag+/Pb2+, Hg2+/Zn2+, Hg2+/Cd2+; separation of Hg2+. Under the same conditions no separation could be achieved by the ion-exchanger Dowex A-1.
  相似文献   

14.
A chloroform membrane system containing a given mixture of dibenzyldiaza‐18‐crown‐6 and palmetic acid was applied for transport of Pb2+ ions. The transport was capable of moving metal ions “uphill”. Thus, it was possible to follow the transfer of Pb(II) from the aqueous source phase to the organic layer and from the organic layer to the receiving phase. The effects of thiosulfate concentration in the receiving phase, palmetic acid and dibenzyldiaza‐18‐crown‐6 concentration in the organic phase on the efficiency of the transport system were examined. By using S2O32? ion as metal ion acceptor in the receiving phase, the amount of lead ion transport across the liquid membrane after 150 minutes is 96 ± 1.5%. The selectivity and efficiency of lead transport from aqueous solution containing Cu2+, Tl+, Ag+, Co2+, Ni2+, Mg2+, Zn2+, Hg2+, Cd2+, Ca2+ were investigated. In the presence of thiosulfate as a suitable masking agent in the source phase, the interfering effects of Ag+ and Cu2+ were diminished drastically.  相似文献   

15.
合成了以1,8-萘酰亚胺为发色团,以联吡啶为离子受体的Zn2+荧光探针,并进行了表征及离子识别性能的研究。研究表明该化合物对Zn2+具有良好的识别性能,同时相对于Ca2+, Cd2+, Co2+, Cu2+, Hg2+, Fe3+, Mn2+, Ni2+, Pb2+等金属离子具有良好的选择性。  相似文献   

16.
The complexation equilibria of the phenolic diazacrown ether derivatives L1L11 with transition and heavy metal ions (Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+ and Pb2+) have been studied in methanol using UV absorption spectrophotometry. A majority of the systems studied formed only ML complexes. Using a ligand with a different position of the substituents on the phenolic side arms (denoted L7) leads to ML2 formation with most of the metal ions. Every ligand forms very strong ML and ML2 complexes with Pb2+, and, in nearly all cases, only a lower limit could be derived for the stability constant. The stability of the complexes generally increases as the length of the para-substituents on the phenol groups increases. Among the metal ions tested, Zn2+ and Hg2+ are the least preferred by alkyl and alkoxy derivatives, respectively.  相似文献   

17.
Organic molecular devices for information processing applications are highly useful building blocks for constructing molecular‐level machines. The development of “intelligent” molecules capable of performing logic operations would enable molecular‐level devices and machines to be created. We designed a series of 2,5‐diaryl‐1,3,4‐oxadiazoles bearing a 2‐(para‐substituted)phenyl and a 5‐(o‐pyridyl) group (substituent X=NMe2, OEt, Me, H, and Cl; 1 a – e ) that form a bidentate chelating environment for metal ions. These compounds showed fluorescence response profiles varying in both emission intensity and wavelength toward the tested metal ions Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, and Pb2+ and the responses were dependent on the substituent X, with those of 1 d being the most substantial. The 1,3,4‐oxadiazole O or N atom and pyridine N atom were identified as metal‐chelating sites. The fluorescence responses of 1 d upon metal chelation were employed for developing truth tables for OR, NOR, INHIBIT, and EnNOR logic gates as well as “ON‐OFF‐ON” and “OFF‐ON‐OFF” fluorescent switches in a single 1,3,4‐oxadiazole molecular system.  相似文献   

18.
A series of macroporous dithiocarbamate chelate resins, III and V, and an oxidized resin, VI, with high adsorption capacity were prepared. The influence of various reaction conditions of amination, dithiocarboxylation, and oxidation were examined. The structure and the conversion of functional groups of resins were confirmed by IR spectra and elemental analysis. The adsorption capacities of Resin II for Hg2+, Cu2+, Zn2+, and Cd2+ are 4.40, 2.44, 1.77, and 1.36 mmol/g, respectively. The adsorption capacities of Resins V and VI for Cu2+. Zn2+, Ni2+, Co3+, Ag+, Hg2+, Cd2+, Pb2+, and Au3+ are 4.07–0.51 and 3.81–0.59 meq ion/g, respectively. The adsorption rate and the influence of pH on the adsorption percentage of the resins for metal ions were examined. Noble metal, transitional metal, and heavy metal ions can be quantitatively adsorbed by the resins. The adsorbed Cu2+, Pb2+, Cd2+, Co3+, and Ni2+ can be quantitatively eluted with 5N HNO3, and the presence of large amounts of Ca2+, Mg2+, Fe3+, and Al3+ did not interfere.  相似文献   

19.
A new chelating resin containing bis[2-(2-benzothiazolylthioethyl)sulfoxide] was synthesized using chloromethylated polystyrene as material and characterized by elemental analysis and infrared spectra. The adsorption capacities of the newly formed resin for Hg2+, Ag+, Cu2+, Zn2+, Pb2+, Mn2+, Ni2+, Cd2+ and Fe3+ were investigated over the pH range 1.0-6.0. The resin exhibited no affinity for alkali or alkaline earth metal ions. The maximum adsorption capacities of the resin for Hg2+, Ag+, Cu2+, Zn2+, Pb2+, Mn2+, Ni2+, Cd2+ and Fe3+ were 1.49, 0.96, 0.58, 0.11, 0.37, 0, 0.24, 0.36 and 0.25 mmol g−1, respectively. In column operation it had been observed that Hg2+ and Ag+ in trace quantity could be separated from different binary mixtures and Hg2+ could be effectively removed from industrial wastewater and the natural water spiked with Hg2+ at usual pH.  相似文献   

20.
A new chemically modified carbon paste electrode by 2,2?-((pyridine-2,6-diylbis(azanylylidene))bis(methanylylidene))diphenol (L) ligand has been made and used as a sensor for determination of trace mercury and cadmium ions with cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. Complexation studies of the ligand with Cu2+, Zn2+, Hg2+, Ni2+ and Cd2+ ions by conductometric method in acetonitrile–ethanol mixture at 25°C show that the ML complexes have formed. The formation constants of complexes were calculated from the computer fitting of the molar conductance–mole ratio data, and the stability of the resulting complexes varied in order of Cd2+ > Hg2+ > Cu2+ > Zn2+ > Ni2+. Then a simple and effective chemically modified carbon paste electrode with L was prepared, and the electrochemical properties and applications of the modified electrode were investigated. Under the optimal conditions, the detection limit was 0.0494 μg L?1 and 0.0782 μg L?1 for cadmium and mercury ions, respectively, and the linear range for both metal ions were from 1 to 100 μg L?1. The electrode shows high sensitivity, reproducibility and low cost, and was successfully applied to determination of Cd2+ and Hg2+ ions in water samples with recovery in the range of 97–101%.  相似文献   

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