Cupric Perchlorate Research Articles

Click synthesis of symmetric bis-triazol ligands and full characterisation of their copper(ii)-complexes

Eight novel ligands were prepared from a known symmetric diaza-18-crown-6 (cyclic ligand) and two commercial N,N′-dimethyl-alkyl diamines (acyclic ligands) via the Cu(I)-catalyzed Huisgen dipolar cycloaddition. All C2-symmetric isolated ligands readily formed stable crystalline 1 : 1-copper(II) complexes with cupric perchlorate. Their structural, electrochemical and physico-chemical properties were fully investigated with the help of X-ray diffraction, cyclic voltammetry, FT-IR, UV-visible, and electron paramagnetic resonance (EPR) spectroscopies. Planar – or nearly planar – arrangement of the two N3-triazole nitrogens and the two tertiary amine pivot nitrogens was found in one single four-coordinated species, in four five-coordinated species, and three six-coordinated species, with one or two solvent molecule(s), or two oxygen atoms of the crown ether, occupying the axial position(s) in the solid sate. The electron-donating or electron-withdrawing effect of the N1-substituent on the triazol was found to influence the Cu(II)/Cu(I) redox potential of all studied complexes in DMF. The EPR-spectrum of cyclic complexes in frozen DMF at 100 K exhibited two mononuclear species, one of them likely promoting the formation of dinuclear species as a minor component, whereas most acyclic complex spectra were quite similar.

Tetra-, penta- and hexacoordinate copper(II) complexes with N3 donor isoindoline-based ligands: Characterization and SOD-like activity

Reaction of 1,3-bis(2′-Ar-imino)isoindolines (HLn, n=1–7, Ar=benzimidazolyl, N-methylbenzimidazolyl, thiazolyl, pyridyl, 3-methylpyridyl, 4-methylpyridyl, and benzthiazolyl, respectively) with Cu(OCH3)2 yields mononuclear hexacoordinate complexes with Cu(Ln)2 composition. With cupric perchlorate square-pyramidal [CuII(HLn)(NCCH3)(OClO3)]ClO4 complexes (n=1, 3, 4) were isolated as perchlorate salts, whereas with chloride CuII(HLn)Cl2 (n=1, 4), or square-planar CuIICl2(HLn) (n=2, 3, 7) complexes are formed. The X-ray crystal structures of Cu(L3)2, Cu(L5)2, [CuII(HL4)(NCCH3)(OClO3)]ClO4, CuIICl(L2) and CuIICl(L7) are presented along with electrochemical and spectral (UV–Vis, FT-IR and X-band EPR) characterization for each compound. When combined with base, the isoindoline ligands in the [CuII(HLn)(NCCH3)(OClO3)]ClO4 complexes undergo deprotonation in solution that is reversible and induces UV–Vis spectral changes. Equilibrium constants for the dissociation are calculated. X-band EPR measurements in frozen solution show that the geometry of the complexes is similar to the corresponding X-ray crystallographic structures. The superoxide scavenging activity of the compounds determined from the McCord–Fridovich experiment show dependence on structural features and reduction potentials.

Co-ordination of a new bis-terpyridine ligand with cupric perchlorate yielding a dinuclear M 2L species

We report the synthesis of a new bis-terpyridine ligand which could potentially yield a variety of polynuclear complexes. An investigation of the co-ordination chemistry of this ligand with Cu(II) ions in a 1:1 ratio yielded a complex with a 2:1 ratio of Cu to ligand. The crystal structure of the dinuclear copper(II) complex shows the two equivalent copper cations are co-ordinated via five donor atoms in a highly distorted square pyramidal arrangement. The structure was solved in a monoclinic space group C2/c with cell parameters, a = 21.340(5), b = 14.004(5), c = 18.368(5) Å, α = 90°, β = 106.575(5)°, γ = 90°, volume = 5261(3) Å 3, Z = 4.

A new C2-symmetric diaza-crown ether–Cu II mononuclear complex containing 1,2,3-triazole ligands

A novel C 2-symmetric lariat ether containing two [1,2,3]triazolo-ligands as sidearms was prepared via a click chemistry approach from known N, N′-dipropargyl-4,13-diaza-18-crown-6 ( 1). The ligand ( 2) readily forms a stable 1:1-complex with cupric perchlorate. A single crystal structure of the centro-symmetric mononuclear complex ( 3) could be determined. The Cu II center displays a distorted six-coordinated octahedral geometry where two triazoles and two pivot nitrogens constitute the basal plane. The axial positions are occupied by two oxygens of the crown ether part. The cyclic voltammograms of a DMF solution of the complex showed two redox processes in our experimental conditions.

Diaqua(N-salicylidene-L-2-phenylglycinate-κ3N,O,O′)copper(II)

The title compound, [Cu(C15H11NO3)(H2O)2], was formed by the reaction of cupric perchlorate, l-α-phenyl­glycine and salicyl­aldehyde. Crystallographic analysis shows that the compound is a new Cu–Schiff base of an amino acid complex. The ligand chelates with CuII in a tridentate fashion. One water mol­ecule is in this ligand plane and another is in an axial position. Extensive hydrogen-bonding interactions are present.

Self-Assembly of L-Cysteine-Copper(II)/Copper(I) Multilayer Thin Films on Gold

Self-assembled multilayer thin films have been prepared on Au substrate by alternate surface derivatization with L-cysteine hydrochloride and cupric perchlorate. The layer-by-layer structure at each step of multilayer formation was investigated by X-ray photoelectron spectroscopy. The measurements indicate that there are two structure modes in the multilayers. One is that Cu2+ sandwiches between two amino acid groups. The other one is that Cu+ is bonded through disulfide and thiolate. This process is also confirmed by cyclic voltammetry of Cu ion at different self-assembled multilayers. Steps further on will lead to repeated multilayer films.

ChemInform Abstract: A Quantitative Study of Substituted Effects on Oxidative Cyclization of Some 2‐Aryl‐substituted Aldehyde Thiosemicarbazones Induced by Ferric Chloride and Cupric Perchlorate.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A quantitative study of substituent effects on oxidative cyclization of some 2‐aryl‐substituted aldehyde thiosemicarbazones induced by ferric chloride and cupric perchlorate

AbstractAs a development of our previous work, we performed a kinetic study of the oxidative cyclization reaction of some 2,4‐diaryl‐substituted aldehyde thiosemicarbazones 1a‐n induced by ferric chloride and by cupric perchlorate. The results of cyclization of 1a‐n were compared to those of the corresponding 2‐methyl derivatives. The kinetic data were analyzed by means of the Hammett's equation.

Self-Assembly of Photoluminescent Copper(I)−Dithiol Multilayer Thin Films and Bulk Materials

Self-assembled multilayer thin films have been prepared on Au and mercaptosilanized glass substrates by alternate surface derivatization with Cu2+ ion and alkanedithiols. The films deposited on glass show intrinsic orange-red photoluminescence and were studied by fluorescence spectroscopy. A strongly photoluminescent solid was also obtained by reaction of 1,6-hexanedithiol with cupric perchlorate in ethanolic solution. Multilayer structures on Au were studied by ellipsometry and X-ray photoelectron spectroscopy (XPS). Both in the solid material and in the self-assembled thin films, XPS measurements suggest Cu is present in the +1 oxidation state. This was also confirmed by cyclic voltammetry of Cu ion adsorbed to a self-assembled monolayer of 1,6-hexanedithiol on gold. Metal−metal interactions in the form of clustering might contribute to the unusual photophysical properties observed in both types of materials.

ChemInform Abstract: A Study of the Mechanism of the Oxidative Cyclization of Benzaldehyde Semicarbazones Induced by Cupric Perchlorate in Acetonitrile.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A study of the mechanism of the oxidative cyclization of benzaldehyde semicarbazones induced by cupric perchlorate in acetonitrile

AbstractTreatment of benzaldehyde semicarbazones 1a‐i with cupric perchlorate in acetonitrile at 40 provided selectively the corresponding 1,2,4‐triazolin‐5‐ones 2a‐i. The relative rate constants for 2a‐i formation were determined by the competitive method. The results obtained showed that electron‐donating substituents (methyl and methoxy) increase the reaction rate, while the reverse was found for electron‐withdrawing substituents (chloro and nitro group). The reactivity data are discussed on the grounds of two possible mechanisms.

Solution thermodynamics of first-row transition elements. 1. Apparent molal volumes of aqueous nickel dichloride nickel diperchlorate cupric chloride and cupric perchlorate from 15 to 55.degree.C

The authors have used a flow densimeter to measure the densities of aqueous solutions of NiCl/sub 2/, Ni(ClO/sub /)/sub 2/, CuCl/sub 2/, and Cu(ClO/sub 4/)/sub 2/ at 10/sup 0/C intervals from 15 to 55/sup 0/C. Infinite dilution apparent molal volumes are determined at each temperature by using the Redlich-Meyer equation. These values are fitted to the polynomial Phi/sub upsilon/ = a + bt + ct/sup 2/. The Pitzer formalism has been used to fit the volume data over the entire concentration range (0-3.5 m).

Soluble Copper Xanthate Complexes

Abstract When solutions of cupric perchlorate (10−6 to 10−2 M) are mixed with solutions containing nonequivalent quantities (concentrations) of xanthate (O-alkyl-dithiocarbonate) ions, clear solutions containing soluble nonionic and ionic complexes are obtained, despite the fact that the solubility product for a given metal xanthate salt may be exceeded by several orders of magnitude. Ultraviolet and visible (UV and VIS) spectroscopy, and dc and ac differential polarography have been employed to study these complex species. The spectral changes taking place on the addition of potassium ethyl xanthate to cupric perchlorate solutions, and also turbidity measurements, indicate that copper xanthate complexes are formed before the precipitation of cuprous ethyl xanthate, Cu(S2 COC 2 H 5). In very dilute solutions containing near equivalent concentrations of the reactants, a spectrum containing three broad maxima (235, 285, and 375 nm) is obtained and is interpreted as due to a nonionic cupric complex, Cu(S2 COC 2 H 5)2, (I). In the presence of excess cupric ions a second complex, an ionized cupric monoxanthate, Cu(S2COC2H5)+, (II), is formed with bands at 256, 283, 325, and 382 nm. The relative concentrations of the reactants determine not only which complex is formed in these dilute solutions, but also whether or not the cuprous xanthate precipitates. The species in solutions giving the spectrum of complex (I) is not stable. It decomposes quickly to cuprous xanthate and dixanthogen. Solutions of the ionic cupric complex (II) are stable for many for many hours. It is suggested that the ionic complex (II) may play a role in activating sphalerite in alkaline solutions.

Use of Ceric Sulfate and Cupric Perchlorate for Titrimetric Analyses of Phenothiazine Derivatives

A method was developed in which phenothiazine derivatives were titrated visually to a colorless end‐point with ceric sulfate. Quantitative recoveries were obtained only for chlorpromazine, acetylpromazine, trifluoperazine, and triflupromazine. The method was also applied to pharmaceutical dosage forms of these drugs. UV photometric detection of the end‐point was found to be applicable only to thiethylperazine and thioridazine. Attempts to develop a quantitative procedure for phenothiazines by photometric titration with cupric perchlorate in acetonitrile were unsuccessful.

Discussion of “Galvanostatic Overpotential Transients and Electrocrystallization Processes on Copper Single Crystals in Solutions of Cupric Perchlorate” [L. H. Jenkins (pp. 630–640, Vol. 117, No. 5)

not Available.

Closure to “Discussion of ‘Galvanostatic Overpotential Transients and Electrocrystallization Processes on Copper Single Crystals in Solutions of Cupric Perchlorate’ [L. H. Jenkins (pp. 630–640, Vol. 117, No. 5)

not Available.

Galvanostatic Overpotential Transients and Electrocrystallization Processes on Copper Single Crystals in Solutions of Cupric Perchlorate

Overpotential transients have been measured on copper single crystal surfaces oriented (100), (110), (111), and (321) undergoing galvanostatic dissolution or deposition in acidic solutions of . In the current density range 1–400 µA/cm2 it is shown that maximum values observed in over‐voltage‐time relationships respond to analytical treatment. For the (100) and (110) the anodic and cathodic overpotential maxima vs. current density relationships were symmetric about the equilibrium point, but not for the (111) and (321). From plots of certain functions of overvoltage maxima vs. current density, orientation sensitive quantities similar to exchange current densities could be calculated. At the low and intermediate current densities it was established that a “deposition anomaly” was observed on all orientations. Deposited material did not seem to occupy crystal lattice positions, and moreover, affected subsequent anodic overpotential‐time relationships in a manner related to the extent of the deposition. In situ photomicrography and goniometric observations were used to determine the orientations and rates of facet development on the various surfaces when subjected to long term deposition or dissolution, and these results are discussed in terms of the relative ease of movement of monatomic steps over the various orientations. A model is proposed of a sequence of events on the surface and in the diffusion layer which provides a self‐consistent explanation of all the experimental data.

Analytical Study of A Perchlosate Ion Selective Membrane Electrode

Abstract A perchlorate ion selective electrode of the liquid ion exchanger membrane type is shown to respond selectively to perchlorate ion acetivity over the 10−1 to 10−3.5 M range in aqueous solutions of pH 4 to 11. The electrode is of some analytical usefulness because of its good selectivity for C10− 4 over common univalent anions and is employed, herjft, for the determination of solubility product constants of potassium perchlorate, hexamminecobaltiperchlorate, tetrapyridine cupric perchlorate, and tris-1, 10-phenanthroline ferrous perchlorate.

Activity Coefficient Ratios of Mixed Electrolytes in Aqueous Solutions at 25°. I. Sulfuric Acid and Cupric Sulfate. II. Perchloric Acid and Cupric Perchlorate

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTActivity Coefficient Ratios of Mixed Electrolytes in Aqueous Solutions at 25°. I. Sulfuric Acid and Cupric Sulfate. II. Perchloric Acid and Cupric PerchlorateV. F. Holland and O. D. BonnerCite this: J. Am. Chem. Soc. 1955, 77, 22, 5833–5835Publication Date (Print):November 1, 1955Publication History Published online1 May 2002Published inissue 1 November 1955https://doi.org/10.1021/ja01627a015RIGHTS & PERMISSIONSArticle Views51Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (311 KB) Get e-Alerts Get e-Alerts

Homogeneous Catalytic Activation of Molecular Hydrogen by Cupric Perchlorate

Homogeneous Catalytic Activation of Molecular Hydrogen by Cupric Perchlorate