Yazar "Dayan, Serkan" seçeneğine göre listele
Listeleniyor 1 - 13 / 13
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Catalytic and biological activities of homoleptic palladium(II) complexes bearing the 2-aminobenzothiazole moiety(Elsevier, 2021) Dayan, Serkan; Tercan, Melek; Özdemir, Fethi Ahmet; Aykutoğlu, Gürkan; Özdemir, Namık; Şerbetçi, Zafer; Dinçer, Muharrem; Dayan, OsmanThe palladium(II) complexes PdL1-3, bearing bi-dentated Schiff base ligands (L1-3) were synthesized and characterized by FT-IR, NMR and single crystal-XRD techniques, and the structural, spectroscopic and electronic properties were obtained using the B3LYP density functional method (DFT). The fabricated complexes were used as catalysts in the reduction of some organic pollutants (4-nitrophenol (4-NP), Rhodamine B (Rh B) and methylene blue (MB)) in water at an ambient temperature. The PdL3 complex was recorded as the best catalyst compared to the other complexes and the highest conversion rates were in the order of MB > RhB > 4-NP. Also, the antimicrobial and antifungal activities of all the compounds (ligands and complexes) and the cytotoxic effects on DU-145 and SH-SY5Y cells were investigated. The PdL1-3 complexes show cytotoxic effects, especially against the SH-SY5Y cells. All the synthesized com- pounds showed moderate antimicrobial and antifungal properties.Öğe Experimental and molecular modeling investigation of (E)-N-{2-[(2-hydroxybenzylidene)amino]phenyl}benzenesulfonamide(Taylor & Francis Ltd, 2013) Ozdemir, Namik; Dayan, Serkan; Dayan, Osman; Dincer, Muharrem; Kalaycioglu, Nilgun O.The Schiff base compound (E)-N-{2-[(2-hydroxybenzylidene)amino]phenyl}benzenesulfonamide has been synthesized and characterized by IR, NMR and Uv-vis spectroscopies, and single-crystal X-ray diffraction technique. In addition, quantum chemical calculations employing density functional theory (DFT) method with the 6311++G(d,p) basis set were performed to study the molecular, spectroscopic and some electronic structure properties of the title compound, and the results were compared with the experimental findings. There exists a good correlation between experimental and theoretical data. Enol-imine/keto-amine tautomerization mechanism was investigated in the gas phase and in solution phase using the polarizable continuum model (PCM) approximation. The energetic and thermodynamic parameters of the enol-imineketo-amine transfer process show that the single proton exchange is thermodynamically unfavored both in the gas phase and in solution phase. However, the reverse reaction seems to be feasible with a low barrier height and is supported by negative values in enthalpy and free energy changes both in the gas phase and in solution phase. The solvent effect is found to be sizable with increasing polarity of the solvents for the reverse reaction. The predicted nonlinear optical properties of the compound are found to be much greater than those of urea.Öğe Nickel (II) complex [NiCl2(DMF)2L2] bearing diaminobenzene and sulfonamide: Crystal structure and catalytic application in the reduction of nitrobenzenes(Pergamon-Elsevier Science Ltd, 2020) Dayan, Serkan; Kayaci, Nilgun; Dayan, Osman; Ozdemir, Namik; Ozpozan, Nilgun KalayciogluA new Bis[N-(2-aminophenyl)benzenesulfonamidej-di-chloro-Bis[O'-N,N-dimethyl-formamide]-nickel (II) complex [NiCl2(DMF)(2)L2] was synthesized in DMF solution in reflux media with NiCl2.2H(2)O and the pre-prepared N-(2-aminophenyl)benzenesulfonamide and the [NiCl2(DMF)(2)L-2] complex was crystallized in DMF/diethyl ether solution, for its single crystal. The complex characterized by FT-IR, elemental analysis, TG-DTA and UV Vis spectrophotometry methods, and its single crystal study were also performed by X-ray spectroscopy. Additionally, the catalytic efficiency of the fabricated [NiCl2(DMF)(2)L-2] complex was determined by UV Vis spectrophotometry in the reduction reaction of 2-nitroaniline (2-NA), 4-nitroaniline (4-NA) and nitrobenzene (NB) in presence of NaBH4 in water. The best conversion obtained as a result of the reduction of nitroarenes in the short time of 10 min. was 62.5 %, which was obtained at the 2-NA reduction. The conversion obtained from of the reduction of nitroarenes, are sequenced as 2-NA (62.5 %) > NB (56.5 %) > 4-NA (25.5%) in 10 min. In addition, the reaction products, both aqueous and short-term, are harmless to the environment, which will provide a significant reaction variety in terms of green chemistry. (C) 2019 Elsevier Ltd. All rights reserved.Öğe One-pot stepwise reductive amination reaction by N-coordinate sulfonamido-functionalized Ru(II) complexes in water(Wiley, 2018) Kayaci, Nilgun; Dayan, Serkan; Ozdemir, Namik; Dayan, Osman; Ozpozan, Nilgun KalayciogluNew complexes of formula [RuCl(p-cymene)(L)] (7-12) were prepared with [RuCl2(p-cymene)](2) and pre-synthesized N-arenesulfonly-o-phenylenediamines (1-6) and characterized using H-1 NMR, C-13 NMR, Fourier transform infrared and UV-visible spectroscopic techniques, and single-crystal X-ray diffraction analysis was performed for one complex (8). Complexes 7-12 were investigated in the reduced imine synthesis reaction (in the presence of HCOONa/HCOOH). The best turnover frequency values were found to be 100 h(-1) for 1 and 99 h(-1) for 6 in the transfer hydrogenative reductive amination reaction of 4-methoxyaniline and 3,4,5-trimethoxybenzaldehyde. The most important feature of this reaction is that it is an environmental friendly procedure because of being conducted in an aqueous environment. That no organic solvent is used allows one to say that this reaction represents green chemistry.Öğe Palladium(II) complexes assembled on solid materials: as catalysts for the -NO2 (nitro) to -NH2 (amine) reactions(Springer Wien, 2020) Dayan, Serkan; Kayaci, Nilgun; Ozdemir, Namik; Dayan, Osman; Kalaycioglu Ozpozan, NilgunHerein, a new series of [PdCl2(L)(2)] complexes where ligands are monodentate amine ligands bearing sulfonamide groups were synthesized, characterized using various techniques such as NMR, FT-IR, UV-Vis, and sc-XRD and investigated for their catalytic performance for the reduction of nitroarenes (2-nitroaniline, 4-nitroaniline, and nitrobenzene) in the presence of NaBH4 in water under heterogeneous conditions. Because the results show that the synthesized complexes are very efficient catalysts, materials using the selected palladium(II) complex supported by multiwall carbon nanotubes, silicon dioxide, and iron(II,III) oxide (Fe3O4) were fabricated by a simple-impregnation methodology, characterized by FT-IR, BET, TEM, and XRD techniques and investigated for their catalytic performance for the same reaction. Thus, a series of supported catalysts was designed with the aim of both enhancing catalytic activity and reducing noble-metal contents. Our findings serve to develop simple catalytic systems and this system can be easily used for catalytic reduction reactions which are the cornerstone of the production of important chemicals. [GRAPHICS] .Öğe Palladium(II) complexes bearing bidentate pyridyl-sulfonamide ligands: Synthesis and catalytic applications(Pergamon-Elsevier Science Ltd, 2015) Dayan, Serkan; Cetin, Ahmet; Arslan, N. Burcu; Ozpozan, Nilgun Kalaycoiglu; Ozdemir, Namik; Dayan, OsmanNew palladium(II) complexes aPd(1-5)(2)], 6-10, (1-5 = bidentate pyridyl-sulfonamide ligands)) were obtained from the reaction between Pd(OAc)(2) and bidentate pyridyl-sulfonamide ligands. The synthesized compounds were characterized by elemental analysis, TG, NMR, IR and X-ray diffraction. The Pd(II) complexes 6-10 were investigated as catalysts for the oxidation of benzyl alcohol to benzaldehyde in the presence of periodic acid as the oxidant and acetonitrile as the solvent under reflux. All the complexes were moderately active catalysts for the catalytic reaction (the oxidation of benzyl alcohol to benzaldehyde), with good yields under mild conditions. (C) 2014 Elsevier Ltd. All rights reserved.Öğe Ruthenium(II) complexes bearing pyridine-based tridentate and bidentate ligands: catalytic activity for transfer hydrogenation of aryl ketones(Wiley, 2012) Dayan, Osman; Dayan, Serkan; Kani, Ibrahim; Cetinkaya, BekirRu(II) complexes of the general formula [RuCl2('NNN??')(L)] (1: 'N?=?Nb, L?=?MeOH; 2: 'N?=?Nb, L?=?CH3CN; 3: 'N?=?Nd, L?=?CH3CN; 4: 'N?=?Np, L?=?CH3CN), [Ru(p-cymene)(NN?ab)Cl]Cl (5a: N?Na?=?2,2'-bipyridine; 5b: N?Nb?=?4,4'-dimethyl2,2'-bipyridine), [Ru('NNN??')(NN?ab)Cl]Cl (6a: 'N?=?Nb, NN?a?=?2,2'-bipyridine; 6b: 'N?=?Nb, NN?b?=?4,4'-dimethyl-2,2'-bipyridine; 7a: 'N?=?Nd, NN?a?=?2,2'-bipyridine; 7b: 'N?=?Nd, NN?b?=?4,4'-dimethyl-2,2'-bipyridine; 8a: 'N?=?Np, NN?a?=?2,2'-bipyridine; 8b: 'N?=?Np, NN?b?=?4,4'-dimethyl-2,2'-bipyridine) and [Ru('NNN??')(NN?a)Cl]BF4 (9a: 'N?=?Nb; NN?a?=?2,2'-bipyridine) were synthesized from the corresponding [RuCl2(p-cymene)]2 dimer, 'NNN??' and NN?ab ligands. The compounds were characterized by elemental analysis, IR and NMR. Complex 9a was studied by X-ray diffraction, confirming its cationic-mononuclear [RuCl(bNNN??b)(NN?a)]+ nature. The synthesized Ru(II) complexes (18) were employed as catalysts for the transfer hydrogenation of ketones to secondary alcohols in the presence of KOH using 2-propanol as a hydrogen source at 82 degrees C. The rates of the transfer hydrogenation reactions strongly depended on the type of NNN?? and ancillary ligands. Copyright (C) 2012 John Wiley & Sons, Ltd.Öğe SBA-15-supported N-coordinate ruthenium(II) materials bearing sulfonamide-type ligands: Effect of ligand backbones on catalytic transfer hydrogenation of ketones and aldehydes(Wiley, 2017) Dayan, Serkan; Kayaci, Nilgun; Ozpozan, Nilgun Kalaycioglu; Dayan, Osman[RuLCl(p-cymene)] (L=N-arylsulfonylphenylenediamine) complexes (2(a-d)) were synthesized from the reaction between [Ru(p-cymene)Cl-2](2) and ligand. Additionally, SBA-15-[RuLCl(p-cymene)] derived catalysts (3(a-d)) were successfully immobilized onto mesoporous silica (SBA-15) by an easily accessible approach. The structural elucidations of 2(a-d) and 3(a-d) were carried out with various methods such as H-1 NMR, C-13 NMR and infrared spectroscopies, elemental analysis, thermogravimetric/differential thermal analysis, nitrogen adsorption-desorption and scanning electron microscopy/energy-dispersive X-ray analysis. The Ru(II) complexes and materials were found to be highly active and selective catalysts for the transfer hydrogenation (TH) reaction of aldehydes and ketones. The influence of various 1,2-phenylenediamines on the reactivity of the catalysts (complexes or materials) was studied and the catalysts (2(d) and 3(d)) with a 4,5-dichlorophenylenediamine substituent showed the best activity (the maximum turnover frequencies are 2916 and 2154h(-1) for TH of 4-fluoroacetophenone, and 6000 and 4956h(-1) for TH of 4-chlorobenzaldehyde).Öğe Synthesis and characterization of SiO2-supported ruthenium complexes containing aromatic sulfonamides: as catalysts for transfer hydrogenation of acetophenone(Royal Soc Chemistry, 2013) Dayan, Serkan; Kalaycioglu, Nilgun Ozpozan; Dayan, Osman; Ozdemir, Namik; Dincer, Muharrem; Buyukgungor, Orhan3-Amino-N-aryl-benzenesulfonamides (1-3) were successfully synthesized by the reaction of m-phenylenediamine and various benzenesulfonyl chlorides. Then, a series of ruthenium complexes (4-6) were prepared from the reaction of [RuCl2(p-cymene)](2) and 1-3. Finally, SiO2-supported Ru(II) complexes (7-9) were prepared by an impregnation method. The synthesized compounds and materials were characterized by different methods such as NMR, FT-IR, TG/DTA, nitrogen adsorption-desorption (BET), SEM and EDX. Also, the solid state structures of 4-6 were determined by single-crystal X-ray diffraction. 4-9 were used as catalysts for the transfer hydrogenation of acetophenone. 4-9 showed good catalytic activity and so the effects of the different groups were also examined. For the transfer hydrogenation of acetophenone, 7-9 had similar activity to 4-6. However, the longer lifetime of 7-9 makes them more advantageous than the non-supported catalysts (4-6) in terms of catalytic cycle. Therefore, the effect of SiO2 was investigated as a catalyst and the results show that excess silicon(IV) oxide was a surprisingly active catalyst for the hydrogenation of acetophenone under these conditions.Öğe Synthesis of a cationic ruthenium(ii) complex and its non-enzymatic glucose-sensing properties(Royal Society of Chemistry, 2023) Dayan, Serkan; Özdemir, Namık; Erdener, Diğdem; Dayan, Osman; Çetinkaya, BekirThe new cationic ruthenium(ii) complex (2) was synthesized via the reaction of N,N′-[1,1′-(pyridine-2,6-diyl)bis(ethan-1-yl-1-ylidene)]bis(2-ethyl-6-methylaniline) and [RuCl2(p-cymene)]2, and it was fully characterized using NMR, FT-IR, single-crystal X-ray diffraction, ESI-MS, UV-vis, CV and thermal analysis methods; theoretical computational characterizations and geometric parameters for 2 were also carried out via quantum chemical calculations using the density functional theory (DFT) method. In addition, the synthesized Ru(ii) complex (2) was immobilized on fabricated RGO-TiO2@FTO to evaluate its non-enzymatic biosensing properties, and the sensing properties of the resulting Ru(ii)-RGO-TiO2@FTO electrode were recorded. As a glucose-sensing model, at an applied potential of +0.34 V, the Ru(ii)-RGO-TiO2@FTO electrode presented a moderately good sensitivity of 62.69 μA mM−1 cm−1. Various modifications of Ru(ii)-RGO-TiO2@FTO-type electrodes, such as the metal complex, and material types and ratios, will enable the design of future biosensor devices with improved performance.Öğe Synthesis of Ruthenium(II) Complexes Containing Tridentate Triamine (?(NNN)over-cap?) and Bidentate Diamine Ligands ((NN)over-cap?): as Catalysts for Transfer Hydrogenation of Ketones(Amer Chemical Soc, 2011) Gunnaz, Salih; Ozdemir, Namik; Dayan, Serkan; Dayan, Osman; Cetinkaya, BekirA series of neutral and cationic Ru(II) complexes (1-10), bearing pyridine-based tridentate ('(NNN) over cap'), pyridine-based bidentate ((NN) over cap'), and mixed '(NNN) over cap' + (NN) over cap' ligands, were synthesized by starting from [RuCl2(DMSO)(4)] and [RuCl2(p-cymene)](2) precursors. Solid-state structures of mixed-ligand complexes 9 and 10 were determined by single-crystal X-ray diffraction. Both complexes are unusual in that (NN) over cap' ligands were spontaneously oxidized in air under base-free conditions to give imine-amine bidentate ligands upon replacement of p-cymene by meridional '(NNN) over cap'. The complexes 1-10 were screened for transfer hydrogenation (TH) of aryl ketones with, 2-propanol. The highest catalytic activity was obtained with the :complexes containing tridentate '(NNN) over cap' and 7, which contain nonsulfonated 2-(aminomethyl)pyridine. However, for complexes 6(a-c), containing p-cymene (a facial tridentate ligand), a slower reaction rate was observed.Öğe Synthesis of ruthenium(II) complexes derived from reduced imine ligands: As catalysts for transfer hydrogenation of ketones(Elsevier Science Sa, 2013) Dayan, Serkan; Kayaci, Nilgun; Kalaycioglu, Nilgun Ozpozan; Dayan, Osman; Ozturk, Esra CircirN-[2-(benzylamino)phenyl]benzenesulfonamide derivatives (1-6) were successfully synthesized by the reaction of imine ligands derived from various N-(2-aminophenyl)benzenesulfonamides and NaBH4. Then, a series of N-coordinate Ru(II) arene complexes 7-12 were prepared from the reaction of [RuCl2(p-cymene)](2) with 1-6. The synthesized compounds were characterized by different methods such as NMR, FT-IR, and elemental analysis. 7-12 were used as catalysts for the transfer hydrogenation (TH) of ketones. At the same time, the effect of various bases such as NaOH, KOH, KOBut and Et3N as organic base were investigated in TH of ketones by 2-propanol as the hydrogen source. 7-12 showed good catalytic activity and so the effects of the different groups were also examined. Crown Copyright (c) 2013 Published by Elsevier B.V. All rights reserved.Öğe Synthesis of some ruthenium(II)-Schiff base complexes bearing sulfonamide fragment: New catalysts for transfer hydrogenation of ketones(Elsevier Science Sa, 2014) Dayan, Serkan; Ozpozan, Nilgun Kalaycioglu; Ozdemir, Namik; Dayan, OsmanFour new ruthenium(II) complexes [RuCl(1-4)(p-cymene)] (1-4 = N-(3-(2-hydroxybenzylideneamino)phenyl) benzenesulfonamides) were synthesized from [RuCl2(p-cymene)](2) with Schiff base ligands containing aromatic sulfonamide fragment, and characterized by spectroscopic techniques including H-1 and C-13 NMR, FT-IR, single crystal X-ray diffraction and by elemental analysis. Additionally, all the synthesized Ru(II) complexes were tested as catalysts for the reactions in the transfer hydrogenation (TH) of acetophenone derivatives. The results showed that these facile synthesized Ru(II) complexes are efficient catalysts in this reaction (turnover frequency: 1260 h(-1) for 6). (C) 2014 Elsevier B. V. All rights reserved.
