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排序方式: 共有97条查询结果,搜索用时 15 毫秒
1.
İlyas Gönül Ender Fakı Burak Ay Muhammet Köse Selahattin Serin 《Transition Metal Chemistry》2018,43(1):73-81
A Schiff base ligand (HL), 2,4-dimethoxy-N-(5-chloro-2-hydroxybenzylidene)-benzenamine, derived from 5-chloro-2-hydroxybenzaldehyde and 2,4-dimethoxyaniline, and its metal complexes [Co(L)2]·CH3OH (1), [Ni(L)2] (2), [Cu(L)2] (3) have been synthesized. The compounds were characterized by analytical and spectroscopic methods. In addition, the structures of the Schiff base HL and its Co(II) complex were determined by single-crystal X-ray analysis. The Co(II) center is six-coordinate, being coordinated to two imine nitrogen, two phenolate oxygen and two methoxy oxygen atoms of two crystallographically independent Schiff base ligands. Luminescence properties of HL and its complexes were investigated both in solution and in the solid state. 相似文献
2.
In this study, the Schiff base ligands H2L1–H2L3 and their CuII, CoII, NiII, FeIII RuIII and VOIV complexes have been prepared and characterized by spectroscopic and analytical techniques. All the complexes are mononuclear.
Keto-enol tautomeric forms of the ligands have been investigated in polar and apolar solvents. The ligands favor the keto-form
in the C7H8 and C6H14. The C–C coupling reaction of the 2,6-di-t-butylphenol has been investigated by the CoII and CuII complexes. Thermal properties of the complexes have been assessed using thermal techniques and similar properties were found.
In the FeIII and RuIII complexes, firstly, the coordinated water molecule is lost from the complex; in the second step, the chloride ion leaves
the molecule in the 300–350 °C temperature range. Finally, the complexes decompose to the appropriate metal oxide at the higher
temperature ranges. The electrochemical properties of the complexes have been studied in the two different solvents (DMF and
CH3CN). 相似文献
3.
Sevim Hamamci Alisir Necmi Dege Recep Tapramaz 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(4):388-397
Three new diclofenac‐based copper(II) complexes, namely tetrakis{μ‐2‐[2‐(2,6‐dichloroanilino)phenyl]acetato‐κ2O:O′}bis(methanol‐κO)copper(II), [Cu2(μ‐dicl)4(CH3OH)2] ( 1 ), bis{2‐[2‐(2,6‐dichloroanilino)phenyl]acetato‐κ2O,O′}bis(1‐vinyl‐1H‐imidazole‐κN3)copper(II), [Cu(dicl)2(vim)2] ( 2 ), and bis{2‐[2‐(2,6‐dichloroanilino)phenyl]acetato‐κ2O,O′}bis(1H‐imidazole‐κN3)copper(II), [Cu(dicl)2(im)2] ( 3 ) [dicl is diclofenac (C14H10Cl2NO2), vim is 1‐vinylimidazole (C5H6N2) and im is imidazole (C3H4N2)], have been synthesized and characterized by elemental analysis, FT–IR spectroscopy, thermal analysis and single‐crystal X‐ray diffraction. X‐ray diffraction analysis shows that complex 1 consists of dimeric units in which the dicl ligand exhibits a bidentate syn,syn‐μ2 coordination mode linking two copper(II) centres. Complexes 2 and 3 have mononuclear units with the general formula [Cu(dicl)2L2] (L is vim or im) in which the CuII ions are octahedrally coordinated by two L and two dicl chelating ligands. The L and dicl ligands both occupy the trans positions of the coordination octahedron. The different coordination modes of dicl in the title complexes were revealed by Fourier transform IR (FT–IR) spectroscopy. The spin matching between the copper(II) centres in the dimeric [Cu2(μ‐dicl)4(CH3OH)2] units was also confirmed by magnetic data to be lower than the spin‐only value and electron paramagnetic resonance (EPR) spectra. The thermal properties of the complexes were investigated by thermogravimetric (TG) and differential thermal analysis (DTA) techniques. 相似文献
4.
Al-Ameen Bariz OmarAli Ahmed Jasim M. Al-Karawi Adil A. Awad Necmi Dege Sevgi Kansz Erbil Agar Zaman Ahmed Hussein Iman Rajab Mohammed 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(5):476-482
Reaction of N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide), C20H18F2N4O2, ( LF ), with zinc chloride and mercury(II) chloride produced different types and shapes of neutral coordination complexes, namely, dichlorido[N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide)‐κ2N,O]zinc(II), [ZnCl2(C20H18F2N4O2)], ( 1 ), and dichlorido[N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide)‐κ4O,N,N′,O′]mercury(II), [HgCl2(C20H18F2N4O2)], ( 2 ). The organic ligand and its metal complexes are characterized using various techniques: IR, UV–Vis and nuclear magnetic resonance (NMR) spectroscopies, in addition to powder X‐ray diffraction (PXRD), single‐crystal X‐ray crystallography and microelemental analysis. Depending upon the data from these analyses and measurements, a typical tetrahedral geometry was confirmed for zinc complex ( 1 ), in which the ZnII atom is located outside the bis(benzhydrazone) core. The HgII atom in ( 2 ) is found within the core and has a common octahedral structure. The in vitro antibacterial activities of the prepared compounds were evaluated against two different bacterial strains, i.e. gram positive Bacillus subtilis and gram negative Pseudomonas aeruginosa bacteria. The prepared compounds exhibited differentiated growth‐inhibitory activities against these two bacterial strains based on the difference in their lipophilic nature and structural features. 相似文献
5.
Antimicrobial activity studies of the binuclear metal complexes derived from tridentate Schiff base ligands 总被引:1,自引:0,他引:1
Tümer Mehmet Köksal Hüseyin Sener M. Kasim Serin Selahattin 《Transition Metal Chemistry》1999,24(4):414-420
Three novel tridentate Schiff base ligands derived fromthe 3-hydroxysalicylaldehyde (H2L1), 4-hydroxysalicylaldehyde (H2L2) and 5-bromosalicylaldehyde (H2L3) with a new amine N-(pyridyl)-2-hydroxy-3-methoxy-5-aminobenzylamine (2) have been prepared. The ligands and their metal complexes have been characterized by elemental analyses, conductivity and magnetic susceptibility measurements, i.r., electronic absorption and 1H and 13C n.m.r. spectroscopy. All complexes are binuclear and, in some, the H2O molecules are coordinated to the metal ion. Antimicrobial activities of the ligands and their complexes have been tested against to the Bacillus subtilis IMG 22 (bacteria), Micrococcus luteus LA 2971 (bacteria) Saccharamyces cerevisiae WET 136 (yeast), and Candida albicans CCM 314 (yeast). Thermal properties of all complexes have been studied by t.g. and d.t.a techniques. 相似文献
6.
Damla Durak Anıl Delikanlı Cahit Demetgül İbrahim Kani Selahattin Serin 《Transition Metal Chemistry》2013,38(2):199-206
An unsymmetrical tetradentate Schiff base (H2L) was synthesized by the reaction of 3-methoxysalicylaldehyde, o-phenylenediamine, and salicylaldehyde in EtOH. H2L was characterized by single-crystallographic X-ray analysis. Its Co(II) and Mn(III) complexes ([CoL] and [MnLCl]) were prepared and immobilized on 3-aminopropyltriethoxysilane functionalized silica gel. The immobilized materials were found to be efficient catalysts for epoxidation of styrene in the presence of tert-BuOOH in acetonitrile at 40 °C. The catalysts can be reused several times without significant loss of performance. 相似文献
7.
Bülbül Hakan Köysal Yavuz Doğan Onur Erman Dege Necmi Ağar Erbil 《Crystallography Reports》2019,64(3):403-406
Crystallography Reports - The title compound, C17H15NOS, crystallizes in the orthorhombic sp. gr. Pca21. Two molecules in the asymmetric unit have similar structure. Crystal structure contains weak... 相似文献
8.
Two-photon absorption excited intramolecular energy transfer and light-harvesting effects are demonstrated in three novel dendritic systems. These systems contain both an antenna structure that can effectively absorb two-photon energy at approximately 800 nm and emit fluorescence at approximately 515 nm and a core moiety that can absorb one-photon energy at approximately 520 nm and emit at approximately 590 nm. Covalently combining the core and antenna functionalities intrinsically changes the optical behavior of the component pieces. The two-photon energy absorbed by the antenna structure is resonantly transferred to the core, where the core's emission intensity is enhanced by 8, 20, and 34 times for the three dendritic systems. 相似文献
9.
Warot-Fonrose B Traverse A Calmels L Serin V Snoeck E 《Micron (Oxford, England : 1993)》2006,37(5):478-485
The trend in reducing device dimension induces new physical properties and requires the development of measurement tools at the nanometer scale. This paper deals with the relation between magnetism and structure of thin films. We have chosen cobalt as a ferromagnetic layer and chromium as a bcc buffer. Magnetic and structural investigations have been led on epitaxial Co/Cr layers grown on MgO (001) substrates. The thickness of the cobalt layer varies from 0.75 to 20 nm. Investigations on the cobalt layer by EXAFS and HRTEM give evidence for a bcc or a hcp structure depending on the cobalt thickness. Magnetic measurements using SQUID indicate that the saturation magnetisation per volume unit is constant for the layers. EELS experiments have been carried out to measure any evolution in the I(L3)/I(L2) ratio for ferromagnetic layers of different thickness. We discuss the influence of structural and magnetic contributions on the evolution of the ratio with the cobalt thickness. 相似文献
10.
Conductivity, X-ray diffraction (XRD), optical absorption and atomic force microscopy (AFM) measurements of CuO thin film were presented. Three distinct electrical conduction contributions with discrete characteristic activation energies were observed. The applicability of various theoretical models was considered to explain results on electrical transport. We extracted important electrical parameters of CuO, which might be useful for its gas sensor applications. 相似文献