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O. V. Mikhailov - One of the best experts on this subject based on the ideXlab platform.
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dft b3lyp calculation of the spatial structure of co ii ni ii and cu ii template complexes formed in ternary systems metal ii ion Dithiooxamide formaldehyde
Russian Journal of Inorganic Chemistry, 2009Co-Authors: D V Chachkov, O. V. MikhailovAbstract:The hybrid density functional theory B3LYP method with the 6-31G(d) basis set and the Gaussian 98 program has been used for calculating the geometric parameters of the Mn(II), Co(II), Ni(II), and Cu(II) complexes with NNSS-donor macrocyclic ligands forming in the course of template processes in the M(II)-Dithiooxamide-formaldehyde systems. The bond lengths and bond angles in the complexes with the MN2S2 metal chelate core are reported. For all M(II) ions, the extra six-membered chelate ring that form as a result of template assembly is rotated through a rather large angle with respect to two five-membered rings and the ring itself is not planar.
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Soft template synthesis of cobalt(III) chelates with 2,8-dithio-3, 7-diaza-5-oxa-nonandithioamide-1,9 and with 2,7-dithio-3,6-diazaoctadien-3, 5-dithioamide-1,8 into cobalt(III)hexacyanoferrate(II) gelatin-immobilized matrix materials
Transition Metal Chemistry, 2005Co-Authors: O. V. Mikhailov, Albina I. Khamitova, Marina A. KazymovaAbstract:The complexing processes in the triple CoIII–Dithiooxamide–methanal and CoIII–Dithiooxamide–glyoxal systems taking place in the KCoFe(CN)6-gelatin-immobilized matrix in contact with aqueous-alkaline solutions (pH~12) containing (Dithiooxamide + methanal) and (Dithiooxamide + glyoxal), have been studied. Template synthesis leading to macrocyclic CoIII coordination compounds with tetradentate N,N,S,S-donor ligands-(2,8-dithio-3,7-diaza-5-oxanonandithioamide-1,9) and (2,7-dithio-3,6-diazaoctadien-3,5-dithioamide-1,8) occurs under these specific conditions. Dithiooxamide, methanal and glyoxal are the ligand synthons in these processes.
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soft template synthesis in copper ii Dithiooxamide methanal copper ii Dithiooxamide ethanal and copper ii Dithiooxamide propanone triple systems in a copper ii hexacyanoferrate ii gelatin immobilized matrix
Transition Metal Chemistry, 2000Co-Authors: O. V. MikhailovAbstract:Novel complexing processes in the CuII–Dithiooxamide–methanal, CuII–Dithiooxamide–ethanal and CuII–Dithiooxamide–propanone triple systems proceeding under specific conditions, to copper(II)hexacyanoferrate(II) gelatin-immobilized matrix systems in contact with aqueous-alkaline (pH ∼ 12) solutions containing Dithiooxamide and methanal, ethanal or propanone, have been studied. It has been shown that template synthesis leading to the formation of macrocyclic coordination compounds (2,8-dithio-3,7-diaza-5-oxanonandithioamide-1,9)copper(II), (2,8-dithio-3,7-diaza-4,6-dimethyl-5-oxanonandithio-amide-1,9)copper(II) and (4,4′,6-trimethyl-2,8-dithio-3,7-diazanonen-6-dithioamide-1,9)copper(II), respectively, takes place under such conditions. Dithiooxamide, methanal, ethanal and propanone act as ligand synthons in these processes.
Mikhailov O. - One of the best experts on this subject based on the ideXlab platform.
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Ni(II)- and Cu(II)-Containing Heterocyclic Compounds with 4,4',6-trimethyl-2,8-dithio-3,7-diazanonen-6-dithioamide-1,9 Obtained in Gelatin-Immobilized Matrices in the Template Synthesis Process
2020Co-Authors: Mikhailov O., Kazymova M., Shumilova T., Vafina L.Abstract:Soft template synthesis of metalheterocyclic compounds with 4,4',6-trimethyl-2,8-dithio-3,7-diazanonen-6-dithioamide-1,9 in the triple systems M(II)- Dithiooxamide- acetone (M= Ni, Cu) in the nickel(II)- and copper(II)hexacyanoferrate(II) gelatin- immobilized matrices has been carried out
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Complex formation in Cu(II)-thioamide-carbonyl compound systems in ethanol solutions
2020Co-Authors: Chmutova G., Shumilova T., Kazymova M., Mikhailov O.Abstract:The structures of metal complexes formed in systems Cu(II)-thioamide- carbonyl compounds in water-ethanol solutions were studied by spectroscopic and quantum-chemical methods. It was found that in systems containing thiocarbohydrazide, the processes of template synthesis in water-ethanol solution and in gelatin-immobilized matrices differ substantially. In the case of Dithiooxamide and dithiomalonamide, no products of template synthesis were detected; these amides give with the Cu2+ ion the chelate complexes with a ratio Cu2+: ligand = 1: 2 and with the N2S 2 coordination core for Dithiooxamide and S4 coordination core for dithiomalonamide. The quantum-chemical calculations in terms of the density functional theory were shown to adequately describe the structures of metal complexes and relative thermodynamic characteristics of the template synthesis processes in the systems under study. © Pleiades Publishing, Inc., 2006
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Complexation reaction on the immobilized matrices: Complexes of iron (III) hexacyanoferrate (II) and some N, O and N, S containing.ligands formed on a thin gelatin layer
NISCAIR-CSIR India, 1992Co-Authors: Mikhailov O., Polovnyak V KAbstract:54-57Complexation reaction occurring between mixed potassium- iron(III) hexacyanoferrates(II), KFe[Fe( CN)6], and N, S or N, O-Containing ligands such as 8-hydroxyquinoline (1) and its alkyl- and oxyalkyl derivatives, 1-nitroso-2-naphthol (2) and its isomer 2-nitroso-Inaphthol, isonitrosoacetone (3), a-benzoinoxime (4), 8-mercaptoquinoline (5) and some of its substituted derivatives (halide, alkyl, S-methyI), Dithiooxamide (6) and its N,N' -diphenylsubstituted derivatives have been studied in thin gelatin layers. With KFe[Fe(CN)6]-matrix, complexation proceeds according to pseudo- SN l-mechanism. The complexation occurs after iron(III) hexacyanoferratet(Il) dissociates in the alkaline medium which proceeds according to two possible ways; one leads to Fe2O3 and [Fe(CN)6]4- anion, the other to Fe(OH)2 and [Fe(CN)6]4-anion. It is noted that in the case of N, O-containing ligands, Fe (ll) chelates are formed and in the case of N, S-containing ligands, Fe (lll) chelates are formed, It is shown that in the case of N, S containing ligands, there is a participation of molecular oxygen in the complexation reactions. Examples of kiaetic curves for the particular systems "potassium, iron (III)-hexacyanoferrate (II) ligand" are presented
Gustavo Rocha De Castro - One of the best experts on this subject based on the ideXlab platform.
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incorporation of Dithiooxamide as a complexing agent into cellulose for the removal and pre concentration of cu ii and cd ii ions from natural water samples
Applied Surface Science, 2013Co-Authors: Alexandre De Oliveira Jorgetto, Rafael I V Silva, M M Longo, Margarida Juri Saeki, Pedro De Magalhaes Padilha, Marco Antonio Utrera Martines, B P Rocha, Gustavo Rocha De CastroAbstract:Abstract The present study describes the incorporation of a complexing agent, Dithiooxamide, into microcrystalline cellulose for use in the pre-concentration of Cu(II) and Cd(II) ions from aqueous samples. The FTIR spectrum of the adsorbent exhibited an absorption band in the region of 800 cm−1, which confirmed the binding of the silylating agent to the matrix. Elemental analysis indicated the amount of 0.150 mmol g−1 of the complexing agent. The adsorption data were fit to the modified Langmuir equation, and the maximum amount of metal species extracted from the solution, Ns, was determined to be 0.058 and 0.072 mmol g−1 for Cu(II) and Cd(II), respectively. The covering fraction ϕ, which was 0.39 and 0.48 for Cu(II) and Cd(II), respectively, was used to estimate a 1:2 (metal:ligand) ratio in the formed complex, and a binding model was proposed based on this information. The adsorbent was applied in the pre-concentration of natural water samples and exhibited an enrichment factor of approximately 50-fold for the species studied, which enabled its use in the analysis of trace metals in aqueous samples. The system was validated by the analysis of certified standard (1643e), and the adsorbent was stable for more than 20 cycles, thus enabling its safe reutilization.
Hiroshi Kitagawa - One of the best experts on this subject based on the ideXlab platform.
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construction of highly oriented crystalline surface coordination polymers composed of copper Dithiooxamide complexes
Journal of the American Chemical Society, 2008Co-Authors: Katsuhiko Kanaizuka, Rie Haruki, Osami Sakata, Mamoru Yoshimoto, Yasuyuki Akita, Hiroshi KitagawaAbstract:Layer-by-layer bottom-up crystal engineering of metal−organic crystals at the surface of sapphire or glass from organic (rubeanic acid and derivatives) and inorganic (Cu2+) components which when mixed in solution form instantly an amorphous solid with high proton conduction.
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preparation and proton transport property of n n diethyldithiooxamidatocopper coordination polymer
Synthetic Metals, 2005Co-Authors: Yuki Nagao, Takashi Kubo, Kazuhiro Nakasuji, Ryuichi Ikeda, Takahiko Kojima, Hiroshi KitagawaAbstract:Abstract A novel proton-conductive copper coordination polymer, (H 5 C 2 ) 2 dtoa Cu (R 2 dtoa H 2 = Dithiooxamide derivatives), was synthesized. From X-ray powder diffraction measurements, the crystal structure of (H 5 C 2 ) 2 dtoa Cu was found to be similar to that of a two-dimensional (2-D) coordination polymer (HOH 4 C 2 ) 2 dtoa Cu. This title coordination polymer was revealed to be a proton conductor by the relative humidity (RH) dependence of AC conductivity measurements. The proton conductivity ( σ p ) was 4.2 × 10 −6 S cm −1 under the RH of 100% and the ionic transport number was more than 0.99. The σ p of (HOH 4 dtoa Cu was two orders of magnitude higher than that of (H 5 C 2 ) 2 dtoa Cu, which would be derived from the existence of-OH groups in the alkyl substituent R.
Santo Lanza - One of the best experts on this subject based on the ideXlab platform.
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Crystal structure of N,N′-bis(4-methylphenyl)Dithiooxamide
International Union of Crystallography, 2015Co-Authors: Antonino Giannetto, Santo Lanza, Giuseppe Bruno, Francesco Nicoló, Hadi Amiri RudbariAbstract:Two half molecules of the title compound, C16H16N2S2, are present in the asymmetric unit and both molecules are completed by crystallographic inversion centers at the mid-points of the central C—C bonds: the lengths of these bonds [1.538 (5) and 1.533 (5) Å] indicate negligible electronic delocalization. The trans-Dithiooxamide fragment in each molecule is characterized by a pair of intramolecular N—H...S hydrogen bonds. In the crystal, molecules are linked by weak C—H..π interactions, generating a three-dimensional network
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solid state luminescence switching of platinum ii Dithiooxamide complexes in the presence of hydrogen halide and amine gases
Chemical Communications, 2007Co-Authors: Francesco Nastasi, Fausto Puntoriero, Natale Palmeri, S Cavallaro, Sebastiano Campagna, Santo LanzaAbstract:In the solid state, a non-luminescent platinum(II) Dithiooxamide species adsorbs gaseous HCl, yielding a tight ion pair species which exhibits photoluminescence; the process is quantitatively reversed on heating or by exposing the sample to ammonia vapors.