Search results for "Organo"
showing 10 items of 1460 documents
A tris-oxovanadium pyrogallate complex: synthesis, structure, and magnetic and electronic properties
2021
International audience; With the aim of identifying new cation-phenolate complexes, we herein investigated the reactivity of pyrogallol (H(3)pgal) with vanadium salts. A trimetallic anionic complex was identified, and found to be formed under a broad set of reaction conditions. This complex, with the formula V3O3(pgal)(3)(3-), consists of three oxovanadium(iv) units connected together by three pyrogallate ligands to afford a bowl-shaped species presenting a pseudo 3-fold symmetry axis. Its crystal structure is reported, as well as its characterisation by a broad set of techniques, including powder X-ray diffraction, thermogravimetric analysis, infrared and Raman spectroscopy, and solid stat…
Properties and structure of cyanate ester/polysulfone/organoclay nanocomposites
2006
In this paper, a cyanate ester (CE) matrix has been modified with polysulfone and an organic montmorillonite (Nanofil 919). The blend was thermally cured in presence of copper acetylcetonate and nonylphenol. The morphology of the cured materials was investigated by wide angle X-ray, scanning and transmission electron microscopy techniques. An intercalate structure of silicate platelets in the cyanate matrix has been obtained. Furthermore, results of thermogravimetric analysis (TGA) suggest that CE/PSF/Nanofil 919 nanocomposites have higher thermal stability than the neat resin, increasing the onset decomposition temperature. Flexural strength distributions of modified and neat cyanate matri…
Radiation curing of diacrylate glycerolate of bisphenol-A in the presence of an organically modified montmorillonite for the production of flame-resi…
2006
Polymerization of an acrylate derivative of bisphenol-A by ionizing radiation in the presence of an organically modified montmorillonite was carried out in order to produce a flame-retardant composite. The measurement of the thermal effect during irradiation indicates that radiation curing of pure resin and resin-clay mixtures occurred in both cases. Moreover, differential scanning calorimetry and dynamic mechanical thermal analysis showed that a curing completion can be obtained by thermal curing after irradiation with a significant increase of the glass transition temperature. The morphology was investigated by X-ray diffraction and transmission electron microscopy. These have indicated t…
Insights into grafting of (3-Mercaptopropyl) trimethoxy silane on halloysite nanotubes surface
2020
Abstract Functionalization of halloysite nanotubes surface by using organosilanes is sensitive to the reaction conditions. Halloysite nanotubes (HNTs) were modified using (3-Mercaptopropyl) trimethoxy silane (MPTMS). The experiments were performed under different reaction conditions including, various solvents [Toluene, Tetrahydrofuran (THF), Ethanol, n-Hexane, 1,4 Dioxane and Acetonitrile], water content in the reaction media, volume of solvent, number of moles of silane and catalysts (triethyl amine, ammonia solution and tetra-ethoxy titanium). The elemental analysis, FT-IR analysis were used to identify the samples, which attained the highest percent of functionalization. SEM image and t…
Structural basis and effect of copper(II) complexes with 4-oxo-thiazolidine ligands on DNA binding and nuclease activity
2020
Abstract Seven novel Copper(II) complexes, namely [Cu(Am4DHotaz)(H2O)2](ClO4) (1), [Cu(Am4DHotaz)(NO3)(MeOH)]·H2O (2), [Cu(Am4Motaz)2(H2O)](ClO4)2·0.83H2O (3), [Cu(Am4Motaz)2(NO3)]NO3·MeOH (4), [Cu(Am4Eotaz)2(NO3)]3(NO3)3·2H2O (5), [Cu(Am4Eotaz)2(ClO4)](ClO4) (6) and [Cu(Am4Eotaz)(ClO4)(H2O)](ClO4) (6a) (HAm4DHotaz = N′-(4-oxothiazolidin-2-ylidene)pyridine-2-carbohydrazonamide, Am4Motaz = N′-(3-methyl-4-oxothiazolidin-2-ylidene)pyridine-2-carbohydrazonamide and Am4Eotaz = N′-(3-ethyl-4-oxothiazolidin-2-ylidene)pyridine-2-carbohydrazonamide), have been successfully synthesized and characterized by several physicochemical techniques and, for 1–6 complexes, single crystal X-ray diffraction. Ha…
Complexes of organometallic compounds
1972
Abstract The configurations of (CH 3 ) 3 PbNCS, (C 6 H 5 ) 3 PbNCS, (C 6 H 5 ) 2 Pb(NCS) 2 , (C 6 H 5 ) 3 Pb(NCS) 2 − and (C 6 H 5 ) 2 Pb(NCS) 4 2− have been investigated in the solid and (except for the insoluble diphenyl derivative) in solution. From infrared spectroscopy it is deduced that the compounds are isothiocyanates in both states, and there is evidence for a polymeric nature of the solid neutral species involving bridging through NCS. PMR and osmometric investigations show that five-coordinate species (CH 3 ) 3 Pb(NCS)·(CH 3 ) 2 CO are present in acetone solution. Possible configurations are discussed.
Characterization of Hydrophilic Gold(I) N-Heterocyclic Carbene (NHC) Complexes as Potent TrxR Inhibitors Using Biochemical and Mass Spectrometric App…
2017
We report here on the synthesis of a series of mono-and dinuclear gold(I) complexes exhibiting sulfonated bis(NHC) ligands and novel hydroxylated mono(NHC) Au(I) compounds, which were also examined for their 'biological activities. Initial cell viability assays show strong antiproliferative activities of the hydroxylated mono(NHC) gold compounds (8 > 9 > 10) against 2008 human ovarian cancer cells even after 1 h incubation. In order to gain insight into the mechanism of biological action of the gold compounds, their effect on the pivotal cellular target seleno-enzyme thioredoxin reductase (TrxR), involved in the maintenance of intracellular redox balance, was investigated in depth. Th…
Structure, magnetic properties and nuclease activity of pyridine-2-carbaldehyde thiosemicarbazonecopper(II) complexes.
2008
New complexes of formulae [Cu(HL 2 )(H 2 O)(NO 3 )](NO 3 ) ( 1 ), [{Cu(L 1 )(tfa)} 2 ] ( 2 ), [{Cu(L 1 )} 2 (pz)](ClO 4 ) 2 ( 3 ) and {[{Cu(L 1 )} 2 (dca)](ClO 4 )} n ( 4 ), where HL 1 = pyridine-2-carbaldehyde thiosemicarbazone, HL 2 = pyridine-2-carbaldehyde 4 N -methylthiosemicarbazone, Htfa = trifluoroacetic acid (CF 3 COOH), pz = pyrazine (C 4 H 4 N 2 ) and dca = dicyanamide [N(CN) 2 ] − , have been synthesized and characterized. The crystal structures of these compounds are built up of monomers ( 1 ), dinuclear entities with the metal centers bridged through the non-thiosemicarbazone coligand ( 2 and 3 ) and 1D chains of dimers ( 4 ). In all the cases, square–pyramidal copper(II) io…
A study of electron transfer in Ru(dcbpy)2(NCS)2 sensitized nanocrystalline TiO2 and SnO2 films induced by red-wing excitation.
2008
Excited state dynamics and electron transfer from the Ru(dcbpy)2(NCS)2 (RuN3) sensitizer to semiconductor nanoparticles were studied using time-resolved femtosecond absorption spectroscopy. We found that excitation of the red wing of the absorption spectrum of the sensitizer populates the (3)MLCT state directly, both in solution and attached on semiconductor nanoparticle films. Electron injection is slowed down and becomes gradually less efficient as excitation moves towards red from the absorption maximum at 535 nm. At 675 nm the injection is non-exponential and characterized by 5, 30 and 180 ps time constants. The non-exponential electron injection observed is assigned to injection from a…
Complexes of organometallic compounds
1966
Abstract The compounds (C2H5)2PbCl2, (C2H5)3PbCl and PbCl2 were studied by paper electrophoresis in aqueous LiCl solutions of various molarities. Determination was made of the formation of chloride complexes in which the electric charge was a function of ligand concentration in the solution. From the results of these experiments, and from a comparative examination of anion exchange data obtained in previous researches, useful information is obtained for determining the ligand concentrations relative to the preponderance of cationic, neutral and anionic complexes in the aqueous solutions. From this information it is possible to assume (C2H5)2PbCl42− and (C2H5)3PbCl32− as the fully coordinate…