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Search results for: metal cation complexation
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The synthesis, x-ray structure and metal cation complexation properties of colored crown with two heterocyclic residues as a part of macrocycle
PublicationZsyntezowano nowy eter koronowy zawierający ugrupowanie azowe, resztę pirolu i pirydyny w pierścieniu makrocyklicznym. Badano zdolność kompleksowania kationów metali w acetonitrylu oraz mieszaninę acetonitryl-woda. Do pomiarów wykorzystano spektrofotometrię UV-Vis. Ustalono strukturę krystalograficzną otrzymanego związku.
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Azomacrocyclic derivatives of imidazole: synthesis, structure, and metal ion complexation properties
PublicationNew azocrown ethers comprising imidazoles in the macrocycle have been synthesized. Imidazole, 2-methyl-, 4-methyl-, and 4-phenylimidazole were incorporated to form macrocyclic units by coupling with the appropriate bis-diazonium salts. The syntheseswere performed under high dilution conditions. The X-ray structure of a water adduct of the 21-membered crown ether derivative of 4-methylimidazole 8 has been solved. Metal...
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Studies of complexation of metal cations by tris(3,6-dioxaheptyl)amine in solution
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Azomacrocyclic derivatives of imidazole: synthesis, structure, and metal ion complexation properties
PublicationOtrzymano nowe azokorony zawierające resztę imidazolu w makropierścieniu. Na drodze sprzęgania z solami diazoniowymiotrzymano pochodne imidazolu 2-metylo, 4-metylo oraz 4-fenyloimidazolu. Synteza była prowadzona w warunkach wysokiego ciśnienia. Dla 21-członowej pochodnej 4-metyloimidazolu określono strukturę jej adduktu z wodą przy pomocy metod rentgenograficznych.Zdolność kompleksowania jonów metali badano spektrofotometrycznie...
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Complexation studies of 3-substituted β-diketones with selected d- and f-metal ions
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A concerted evolution of supramolecular interactions in a {cation; metal complex; π-acid; solvent} anion-π system
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Silicon polypodands: powerful metal cation complexing agents and solid–liquid phase-transfer catalysts of new generation
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Lower Rim Substituted p-tert-Butyl Calix[4]arenes(V). Synthesis of New 5,11,17,22-tetrakis-p-tert-Butyl-25-27-bis(dialkoxyphosphorylmethoxy)calix[4] arenes and Cation Complexation Studies in Ion Selective Membrane Electrodes.
PublicationZaprezentowano syntezę i właściwości trzech nowych związków (2-4), bis podstawionych na dolnym obrzeżu grupami z resztą fosforylową. Związki te były badane jako jonofory w membranowych elektrodach jonoselektywnych (ISE) wykazując selektywność na kationy Rb+,K+ oraz duży i płaski kation guanidyniowyG+). Badano korelację pomiędzy stereo-strukturą związków a ich selektywnością w ISE. Stałe trwałości kompleksów z kationami metali...
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Cation sensing by diphenyl-azobenzocrowns
PublicationMetal cations complexation and proton binding by 13- and 16-membered diphenyl-azobenzocrowns and diphenyl-hydroxyazobenzocrowns were studied in acetonitrile using spectroscopic methods: UV–vis spectroscopy, spectrofluorimetry, and 1H NMR spectroscopy. Phenyl moieties in benzene rings were found to affect binding strength alkali and alkaline earth metal cations and hydrogen ion, and affect tautomeric equilibrium of hydroxyazobenzocrowns....
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Chromogenic azomacrocycles with imidazole residue: Structure vs. properties
PublicationNew diazo macrocycles linked by hydrocarbon chain bearing imidazole or 4-methylimidazole residue have been synthetized with satisfactory yield (24–55%). The structure of macrocycles was confirmed by X-ray analysis and spectroscopic methods (1H NMR, MS, FTIR). Metal cation complexation studies were carried out in acetonitrile and acetonitrile-water system. It was found that azomacrocyles form triple-decker complexes with lead(II)....
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Do Phenyl Substituents Affect the Properties of Azobenzocrown Derivatives?
PublicationNew products of photo- and thermal rearrangements of 19-membered azoxybenzocrown with phenyl substituents in benzene rings in the para positions to oligooxyethylene fragments are characterized. The yields of photochemical transformations depend on the solvent. Para-hydroxyazocrown is formed with yields over 50% in propan-2-ol. Ortho-hydroxyazobenzocrown is obtained with yields up to 70% in toluene/acetic acid mixture. Macrocyclic...
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Products of Photo- and Thermochemical Rearrangement of 19-Membered di-tert-Butyl-Azoxybenzocrown
PublicationThe preparation and characterization of products of the photochemical and thermochemical rearrangements of 19-membered azoxybenzocrowns with two, bulky, tert-butyl substituents in benzene rings in the para positions to oligooxyethylene fragments (meta positions to azoxy group, i.e., t-Bu-19-Azo-O have been presented. In photochemical rearrangement, two colored typical products were expected, i.e., 19-membered o-hydroxy-m,m′-di-tert-butyl-azobenzocrown...
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Chemical investigations of the MoO3 doped by K films deposited FTO
Open Research DataMoO3 thin films were synthesized via thermal annealing of thin, metallic Mo films deposited onto the FTO substrate using a magnetron sputtering system. The influence of photointercalation of alkali metal cation (K+) into the MoO3 structure on the photoelectrochemical properties of the molybdenum trioxide films was investigated. The chemical characterisation...
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Metals and metal-binding ligands in wine: Analytical challenges in identification.
PublicationBackground Due to important role of metals in the vinification process as well as their impact on the human health, their content in this alcoholic beverage has been extensively studied by many researchers. It is already known that speciation of metals determines their toxicity and bioavailability as well as influences their activity. Understanding the chemistry and knowing the structures of metal complexes could have relevant...
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Lower Rim Substituted p-tert-Butyl-Calix[4]arene. Part 16. Synthesis of 25, 26, 27, 28-tetrakis(piperidinethiocarbonylmethylene)-p-tert-butylcalix[4]arene and its interaction with metal ions
PublicationThe synthesis, characterisation and X-ray crystal structures of p-tert-butyl-calix[4]arenethioamide L and its complex with lead L-Pb2+ is reported. The cation-binding properties in solution have been assessed by liquid-liquid extraction of the metal picrates from water into dichloromethane and by stability constants determination in acetonitrile using UV-absorption spectrophotometry or potentiometry. The compound was used as active...
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Study of the anticancer potential of Cd complexes of selenazoyl-hydrazones and their sulfur isosters
PublicationThe biological activity of Cd compounds has been investigated scarce since Cd has been recognized as a human carcinogen. However, the toxicity of cadmium is comparable to the toxicity of noble metals such as Pt and Pd. The paradigm of metal toxicity has been challenged suggesting that metal toxicity is not a constant property, yet it depends on many factors like the presence of appropriate ligands. Studies on anticancer activity...
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Chromogenic derivatives of new bis(phenylhydrazono-1H-tetrazol-5-yl-acetonitriles) - synthesis and properties
PublicationDerivatives of bis(phenylhydrazono-1H-tetrazol-5-yl-acetonitriles) with oxygen and sulphur atoms in the structure of aliphatic chains were successfully synthesised. The correlation between the ligand structure and its complexation properties was investigated by absorption spectroscopy. The formation of complexes of presented compounds with metal cations (Cu2+, Ni2+, Zn2+, Co2+, Fe2+ and Pb2+) was studied. Ligands 5-8 were additionally...
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Artificial neural network prophecy of ion exchange process for Cu (II) eradication from acid mine drainage
PublicationThe removal of heavy metal ions from wastewater was found to be significant when the cation exchange procedure was used effectively. The model of the cation exchange process was built using an artificial neural network (ANN). The acid mine drainage waste’s Cu(II) ion was removed using Indion 730 cation exchange resin. Experimental data from 252 cycles were recorded. In a column study, 252 experimental observations validated the...
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Novel Diazocrowns with Pyrrole Residue as Lead(II) Colorimetric Probes
PublicationNovel 18- and 23-membered diazomacrocycles were obtained with satisfactory yields by diazocoupling of aromatic diamines with pyrrole in reactions carried under high dilution conditions. X-ray structure of macrocycle bearing five carbon atoms linkage was determined and described. Compounds were characterized as chromogenic heavy metal ions receptors. Selective color and spectral response for lead(II) was found in acetonitrile and...
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Development of a vortex-assisted switchable-hydrophilicity solvent-based liquid phase microextraction for fast and reliable extraction of Zn (II), Fe (II), Pb (II), and Cd (II) from various baby food products
PublicationThis manuscript describes the development of a novel liquid phase microextraction (LPME) method for the extraction and determination of Zn (II), Fe (II), Pb (II), and Cd (II) in various infant/baby food and supplements products. The method is based on vortex-assisted extraction combined with a switchable-hydrophilicity solvent (SHS) sample preparation. The SHS, which undergoes reversible phase changes triggered by pH change, enables...