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1.
It was established that the compounds formed by the cations in amine complexes of nickel(II) and copper(II) and the anions
of polyoxometallates are capable of reacting stoichiometrically with gaseous ammonia when in the hydrated state. Some of the
studied compounds are characterized by high sorption capacity (up to 40 molecules of adsorbate to a formula unit of the complex)
and exhibit selectivity in the sorption of ammonia in the presence of water vapor.
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Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 3, pp. 189–195, May–June, 2007. 相似文献
2.
Catalytic activity of nickel(II), copper(II) and oxovanadium(II)‐dihydroindolone complexes towards homogeneous oxidation reactions 下载免费PDF全文
Mohamed Shaker S. Adam 《应用有机金属化学》2018,32(4)
Three novel paramagnetic metal complexes (MH2ID) of Ni2+, Cu2+ and VO2+ ions with 3‐hydroxy‐3,3’‐biindoline‐2,2’‐dione (dihydroindolone, H4ID) were synthesized and characterized by different spectroscopic methods. The ligand (H4ID) was synthesized via homocoupling reaction of isatin in presence of phenylalanine in methanol. Complexation of low valent Ni2+, Cu2+ ions and high valent VO2+ ions with H4ID carried out in 1: 2 molar ratios. A comparison in the catalytic potential of paramagnetic complexes of low and high valent metal ion was explored in the oxidation processes of cis‐cyclooctene, benzyl alcohol and thiophene by an aqueous H2O2, as a green terminal oxidant, in the presence and absence of acetonitrile, as an organic solvent, at 85 °C. NiH2ID, CuH2ID and VOH2ID show good catalytic activity, i.e. good chemo‐ and regioselectivity. VOH2ID has the highest catalytic potential compared to both Ni2+‐ and Cu2+‐species in the same homogenous aerobic atmosphere. Catalytic oxidation of other alkenes and alcohols was also studied using NiH2ID, CuH2ID or VOH2ID as a pre‐catalyst by an aqueous H2O2. A mechanistic pathway for those oxidation processes was proposed. 相似文献
3.
M. Gaber A. F. Rehab D. F. Badr-Eldeen 《Journal of Thermal Analysis and Calorimetry》2008,91(3):957-962
The macrocyclic complexes of Co(II) and Ni(II) having chloride or thiocyanate ions in the axial position have been synthesized
and characterized. These complexes are synthesised by the template condensation of o-phenylenediamine or 2,3-butanedionedihydrazone with the appropriate aldehydes in NH4OH solution in the presence of the metal ions, Co(II) and Ni(II). The complexes were characterized by spectroscopic methods
(IR, UV-Vis and ESR) and magnetic measurements as well as thermal analysis (TG and DTA). The results obtained are commensurate
with the proposed formulae. Spectral studies indicate that these complexes have an octahedral structure. From conductivity
measurements the complexes are non-electrolytes. The kinetic of the thermal decomposition of the complexes was studied and
the thermodynamic parameters are reported. 相似文献
4.
The rate of adsorption of water vapor by compounds obtained from cationic copper(II) and nickel(II) ammine complexes and polyoxometallate
anions may be described by the linear driving force mass transfer model as one or two parallel processes. The differences
observed were attributed to differences in the crystal structure of the adsorbents.
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Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 2, pp. 112–117, March–April, 2007. 相似文献
5.
Tatiana V. Burova Elena P. Varfolomeeva Valerij Ya. Grinberg Thomas Haertlé Vladimir B. Tolstoguzov 《Macromolecular bioscience》2002,2(6):286-292
Thermal denaturation and renaturation of soybean trypsin (Kunitz) inhibitor (STI) were studied by high-sensitivity differential scanning calorimetry in the presence of polysaccharides (dextran, ι- and κ-carrageenans, gum arabic, pectins and dextran sulfate). This study was carried out under conditions of both thermodynamic incompatibility and complex formation of STI and polysaccharides. The presence of polysaccharides did neither influence the denaturation temperature nor the denaturation enthalpy of STI under conditions of their incompatibility with the protein. No polysaccharide (except gum arabic) affected the ability of STI to renature and recover its inhibitory activity after thermal denaturation. At acidic pH values, the protein was shown to form electrostatic complexes with pectins and dextran sulfate. Substantial destabilisation of STI bound to dextran sulfate was observed. In the case of STI/pectin complexes, either a decrease or increase in the stability of STI was observed depending on the complex composition and esterification degree of pectin. The mechanism behind the changes in stability of STI bound to the polysaccharide matrix is discussed. Thermal denaturation of STI in complexes with dextran sulfate and pectin was completely irreversible. This observation indicates a possibility of suppressing antinutritional activities of trypsin inhibitors in soy products.
6.
O. V. Kravchenko L. V. Tsymbal Ya. D. Lampeka 《Theoretical and Experimental Chemistry》2007,43(2):131-137
A phase transfer isocationic substitution of lattice constituent macrocyclic complexes by copper(II) aqua complexes occurs
upon the interaction of crystalline mono-and bis(macrocyclic) copper carboxylate complexes with acetonitrile solutions of
copper(II) ammine complex. On the other hand, these materials do not react with cupric bis(ethylenediamine).
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Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 2, pp. 124–129, March–April, 2007. 相似文献
7.
Mononuclear copper(Ⅱ), nickel(Ⅱ) and cobalt(Ⅲ) tetracoordinate macrocyclic complexes were synthesized and spectroscopically characterized. The crystal structure of the three compounds were determined by X-ray crystallography. The electrochemical experimental results indicate that the three complexes could interact with DNA mainly by electrostatic interaction. The interaction of tetracoordinate macrocyclic cobalt(Ⅲ) complex with DNA was studied by cyclic voltammetry and UV-vis spectroscopy. The experimental results reveal that tetracoordinate macrocyc- lic cobalt(Ⅲ) complex could interact with DNA by electrostatic interaction to form a 1 : 1 DNA association complex with a binding constant of 7.50 ×10^3 L·mol^-1. 相似文献
8.
Five new Ni(II) Schiff base complexes [NiLx(Solv)2] denoted by NiLx, x = 1–5, were synthesized and characterized. The Schiff base ligands were synthesized from the condensation of 5-bromo-2-hydroxy-3-nitrobenzaldehyde with different aliphatic and aromatic diamines. The X-ray crystal structure of NiL3 was determined. The ligands and complexes were tested as antibacterial agents against two gram(+) and two gram(?) human pathogenic bacteria. The complexes showed moderate antibacterial activity against both gram type bacteria. The new Ni(II) complexes showed enhanced antibacterial activity compared to the previously reported Cu(II) complexes of the same ligands. 相似文献
9.
H. Langfelderová 《Journal of Thermal Analysis and Calorimetry》1994,41(4):955-970
Dehydration steps of aquacopper(II) complexes with homogeneous and heterogeneous coordination sphere are investigated from the view point of structural changes taking place under their heating to the decomposition temperature and during the dehydration. The role of loosening of intra-and intermolecular hydrogen bonds in the decomposition reaction for the structure changes of the remainder, the structural presumptions of the reactants for lower hydrates formation are discussed. Activation parameters of dehydration were found to be the lower, the smaller are the structure differences between the reactants and products. They do not reflect the bond length central atomvolatile ligand, much more the overall structure differences between the starting and resulting compounds. From all data on crystal and molecular structures of dehydrated compounds is the reaction pathway best indicated by anisotropic temperature parameters of donor atoms corrected for the thermal movement of the central atom: the higher these values in the bond direction are, the lower the values of activation energies of dehydration are. 相似文献
10.
11.
A. M. Donia 《Journal of Thermal Analysis and Calorimetry》1993,39(3):323-332
A number of copper(II) complexes of some aromatic diamines have been prepared and characterized. The thermal stabilities of the complexes were studied and discussed in terms of covalent bond character, chelate ring size and angle strain. On the other hand, the effective role of the anions on the decomposition pathways was also considered. Moreover, the nature of interaction of the solvent of crystallization has also been investigated.
Zusammenfassung Es wurde eine Anzahl von Kupfer(II)-komplexen einiger aromatischer Diamine hergestellt und beschrieben. Die thermische Stabilität der Komplexe wurde als Funktion des kovalenten Bindungscharakters, der Chelatringgröße und der Winkelspannung untersucht und diskutiert. Andererseits wurde auch der Einfluß der Anionen auf den Zersetzungsweg in Erwägung gezogen. Außerdem wurde auch die Wechselwirkung zwischen Lösungsmittel und Kristallisierung untersucht.相似文献
12.
The rates of the adsorption and desorption of methanol and ethanol vapor to and from compounds formed by cationic copper(II)
and nickel(II) amine complexes and polyoxometallate anions can be described in the linear driving force transfer model as
one or two parallel processes. It was proposed that the differences observed should be attributed to the different crystal
structures of the adsorbents. The compound consisting of a nickel tetramine complex and [HSiW12O40]3− anion displays high selectivity toward ethanol relative to methanol.
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Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 5, pp. 291–298, September–October, 2007. 相似文献
13.
Brunilde Castano Tommaso Pedrazzini Massimo Sisti Emma Gallo Fabio Ragaini Nicola Casati Alessandro Caselli 《应用有机金属化学》2011,25(11):824-829
The synthesis and characterization of copper(I) complexes of the novel pyridine‐containing macrocyclic ligand (PC‐L) and their use as catalysts in the Henry reaction are reported. The pyridine‐based 12‐membered tetraaza macrocyclic (PC‐L) ligand 1 can be obtained in good overall yield (85%) from commercially available starting materials. The Cu(I) complexes showed good catalytic activities in the Henry reaction of different aldehydes and nitroalkanes. Remarkable diastereoselectivity was observed when isatine was reacted with nitroethane under catalytic conditions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
14.
The new zinc ternary complexes [Zn(cyclen)NO3]ClO4 (I), [Zn2(cyclen)2(m-nic)](ClO4)3 (II), [Zn2(cyclen)2(m-pic)](ClO4)3 (III) (cyclen=1,4,7,10-tetraazacyclododecane; nic=nicotinic acid; pic=picolinic acid) were synthesized and their spectral and thermal properties were investigated. The compounds were characterized
by elemental analysis, IR spectroscopy and TG/DTG, DTA methods. Moreover, the way of coordination of pyridinecarboxylate anions
was proposed on the basis of the spectral data and consequently proved with results of X-ray structure analysis.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
15.
《Journal of Coordination Chemistry》2012,65(23):2621-2627
Schiff-base complexes of cobalt(II), nickel(II), copper(II) and, zinc(II) with 3-ethoxysalicyliden-p-aminoacetophenoneoxime (HL) were prepared and characterized on the basis of elemental analyses, IR, 1H- and 13C-NMR, electronic spectra, magnetic susceptibility measurements, molar conductivity and thermogravimetric analyses (TGA). A tetrahedral geometry has been assigned to the complexes. 相似文献
16.
The photochemical behavior of cobalt(III) and nickel(II) complexes on excitation in the charge-transfer bands is reviewed in this article with particular reference to the study of intermediates. Investigations on the photoredox reactions of cobalt(III) and nickel(II) complexes using flash kinetic spectroscopic methods reveal details on the characteristics of the intermediates produced from the charge-transfer excited states of these metal complexes. The reactive species produced on photolysis of cobalt(III)-amine complexes activate molecular oxygen, producing mononuclear and dinuclear dioxygen species coordinated as superoxo and peroxo forms. Cobalt(III)-amino-acid complexes on photolysis lead to the formation of cobalt(III)-alkyl complexes which are identified as transients. The spectra and the decay kinetics are described with the view to elucidate mechanistic details. Nickel(II) macrocyclic complexes on excitation in the charge-transfer bands lead to oxidation of the metal centre. Scavenging experiments using dioxygen, alcohols and acids were carried out to understand the mechanistic details. 相似文献
17.
Gup R Kirkan B 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,62(4-5):1188-1195
Two types of copper(II) and nickel(II) complexes derived from benzophenone anthranoylhydrazone (L1), 2-acetonaftanone anthranoylhydrazone (L2), 4-phenylacetonaftonone anthranoylhydrazone (L3), benzophenone salicyoylhydrazone (L4), 2-acetonaftanon salicyoylhydrazone (L5), 4-phenylacetonaftanon salicyoylhydrazone (L6) and bidentate heterocyclic base [1,10-phenanthroline (phen)] with general stoichiometry [ML2] and [ML(phen)]Cl have been synthesized and characterized by elemental analysis, infrared spectra, UV-vis electronic absorption spectra and magnetic susceptibility measurements. The effect of varying pH and solvent on the absorption behavior of both ligands and complexes have been investigated. According to the IR spectra, the ligands act as monobasic bidentate and coordination takes place in the enol tautomeric form. 相似文献
18.
Małecka J Lewandowska U Kamiński R Mames I Więckowska A Bilewicz R Korybut-Daszkiewicz B Woźniak K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(44):12385-12395
Multicenter (bi-, tri-, and tetranuclear) tetraazamacrocyclic complexes were self-assembled from Ni and Cu tetraazamacrocyclic mononuclear units and α,ω-diamines as building blocks. The structures of all compounds studied were proved by spectroscopic methods (ESI MS and NMR spectroscopy). Electrochemical experiments revealed reversible one-electron electrode processes at each of the Ni(2+) and Cu(2+) centers with formation of metal cations in oxidation state +3. Long linkers allow bi- and trinuclear complexes with noninteracting metal centers to be obtained. In the case of the short linkers (e.g. ethylenediamine) higher, trinuclear species are formed as major product. The structures of the bis- and tris-macrocyclic systems were confirmed by single-crystal X-ray diffraction. The tris-macrocyclic systems form cations in the shape of triangles partially filled with counterions and solvent molecules. The cations form positively charged layers, which interact in the crystal lattice with the neighboring negatively charged layers of anions. In solution, the trinuclear complexes exhibit strong host-guest interactions with 9,10-dimethyltriptycene due to complementarity of shape and size of this guest molecule. The association constants were determined by NMR spectroscopy and voltammetry, and very good agreement was obtained. The structural flexibility of the tetranuclear complex with long linkers allows for attractive interactions between the metal-complexing macrocycles that result in folding of the molecule. On the contrary, no folding is possible in the case of short linkers consisting of two CH(2) groups. 相似文献
19.
《印度化学会志》2021,98(11):100182
The reaction of (Z)-2-(phenyl(2-(pyridin-2-yl)hydrazono)methyl)pyridine (L) and copper(II) salt in methanol yields a series of five pentacoordinated mononuclear complexes. The molecular formulations of these complexes are as [Cu(L)(ImH)2](ClO4)2 (1), [Cu(L)(2-MeImH)2](ClO4)2 (2), [Cu(L)(2-EthImH)2](ClO4)2 (3), [Cu(L)(BenzImH)2](ClO4)2 (4) and [Cu(L)(2-MeBenzImH)2](ClO4)2 (5) (where ImH = Imidazole, 2-MeImH = 2-Methylimidazole, 2-EthImH = 2-Ethylimidazole, BenzImH = Benzimidazole, 2-MeBenzImH = 2-Methylbenzimidazole). The room temperature magnetic moment values are in the range 1.79–1.81 B M. The conductance measurements suggest that they are electrolytic in nature. The DFT calculations were performed to get information about the structures of the complexes. The copper(II) centre in all complexes is a Penta-coordinated. The proligand has NNN donor sites viz., two pyridine N and one azomethine N atoms, whereas co-ligand coordinates through pyridine N atom forming two five-membered chelate rings. The τ5 values of these complexes are in the range 0.177–0.495. Both pro and co-ligands are neutral. X-band Epr spectral measurements have been carried out to authenticate the paramagnetic behaviours of all complexes. The stability of the copper(II) centre was examined using cyclic and differential pulse Voltammetry. The IC50 and SOD activity values for all complexes reveal that they are good SOD active complexes. The IC50 value of present complexes remains in the range 26–43 μM. 相似文献
20.
Thermal and/or photochemical conversion of a series of copper(II) complexes containing mixed dithiocarbamato–alcohol ligands, CuII(Et2dtc)+ . . . Y− (Y=ClO4−, NO3−), into CuII(Et2dtc)Cl in chloroalkane/alcohol solutions, where chloroalkane=CCl4, CHCl3 or CH2Cl2 and alcohol=MeOH, EtOH or i-BuOH, proceeds in chloroalkanes. Both reactions follow a similar pathway which is more effective the stronger the acceptor properties of chloroalkanes and the weaker the coordinating abilities of alcohols are. A detailed reaction mechanism is proposed which well fits the experimental results obtained by EPR and UV–VIS spectra and quantum yields. 相似文献