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Öğe Mixed ligand complexes of acesulfame/nicotinamide with earth alkaline metal cations MgII, CaII, BaII and SrII : synthesis and characterization(Hittite Journal of Science and Engineering, 2014-12-31) Yurdakul, Ömer; Köse, Dursun AliI n the scope of this study, acesulfame (ace, acs)-nicotinamide (na) mixed ligand complexes of Mg(II), Ca(II), Sr(II) and Ba(II) were synthesized for the first time. Possible formulas for complexes were determined as [Mg(H2 O)4 (na)2 ](acs)2 , [Ca(H2 O)6 (na)2 ](acs)2 , [Sr(H2 O)7 (na)2 ](acs)2 , [Ba(H2 O)7 (na)2 ](acs)2 ). It was observed that acesulfame ligands within structure were located two moles each at outer surface of coordination sphere acting as counter-ion allowing the charge balance of structure. The solubility of compounds gaining ionic character in this way was determined as quite well as compared to complex structures. Characterizations of complexes synthesized were performed via melting point analysis, elemental analysis, mass spectroscopy and FT-IR spectroscopy methods. Thermal properties of complexes obtained were determined with tandem TG-DTG and DTA techniques. It was found that the coordination spheres of metal cations within compounds obtained in this study were filled with nicotinamide and aqua ligands.Öğe Mn(II) and Co(II) mixed-ligand coordination compounds with acesulfame and 3-aminopyridine: synthesis and structural properties(Taylor & Francis Ltd, 2021) Yurdakul, Ömer; Köse, Dursun Ali; Şahin, Onur; Özer, DemetTwo mixed ligand complexes containing acesulfame (acs) and 3-aminopyridine (3-ap) ligands of Mn(II) and Co(II) were synthesized. The obtained compounds were characterized by various analysis methods. The geometries of complexes, C18H28MnN6O12S2 (1) and C18H32CoN6O14S2 (2), are distorted octahedra. Coordination of metal cations is provided by two molecules of 3-ap and four water ligands. In both structures, the 2+ charge of the metal required two monoanionic acs molecules located outside the coordination sphere. Complex 1 contains no hydrate water, while 2 contains two molecules of hydrate water. The crystal system of 1 is monoclinic and space group P2(1)/c, while the crystal system of 2 is triclinic and space group P-1. Data on the removal of hydrate and crystalline waters in structures from thermal analysis curves support the described molecular structures. The bending vibrations of the bonds obtained from the FT-IR spectra match the crystal structure described. As a result of thermal analysis of both complexes, it was determined that the relevant metal cations remained in the reaction vessel as oxide (MnO and CoO) residues.Öğe Novel monoanionic diphenate-nicotinamide/N,N-diethylnicotinamide complexes of Ni-II, Zn-II. Synthesis, structural investigations and hydrogen adsorption study(Elsevier, 2020) Yurdakul, Ömer; Şahin, Zarife Sibel; Köse, Dursun Ali; Şahin, Onur; Akkurt, FatihThe coordination compounds and polymers in which the transition metals are taken centrally are of interest due to their very different properties. The studies on the synthesis and structural properties of these compounds due to their potential applications for nanotechnology, sensor applications, magnets, optoelectronics, energy conversation and storage, gas storage, separation, catalysis and similar industrial applications are of great interestÖğe Novel Non-Metal Cation (NMC) Pentaborate Salts of Some Amino Acids(Mdpi, 2019) Sızır, Ümit; Yurdakul, Ömer; Köse, Dursun Ali; Akkurt, FatihNon-metal cation (NMC) pentaborate structures, in which some amino acids (valine, leucine, isoleucine, and threonine) were used as cations, were synthesized. The structural characterization of molecules was carried out by elemental analysis, FT-IR, mass, B-11-NMR, and thermal analysis (TGA/DTA) methods. The hydrogen storage capacity of molecules was also calculated by taking experimental results into consideration. The FT-IR spectra support the similarity of structures. The characteristic peaks attributable to pentaborate rings and amino acids were observed. When thermal analysis data were examined, it was observed that pentaborate salts gave similar degradation steps and degradation products. As a final degradation product of all thermal analysis experiments, a glassy form of B2O3 was observed. The valine pentaborate is the most thermally stable. Also, the amounts of hydrate water outside the coordination sphere of the compounds were determined by thermal analysis curves. The peaks of boric acid, triborate, and pentaborate structures were obtained in ppm with the B-11-NMR results of synthesized pentaborate compounds. With powder X-ray spectroscopy, all structures were found to be crystalline but not suitable for single-crystal X-ray analysis. The molecular cavities of the compounds detected by BET were found to be 3.286, 1.873, 2.309, and 1.860 g/cm(3), respectively. A low number of molecular cavities can be interpreted in several existing hydrogen bonds in structures. The hydrogen storage capacities of the molecules were found to be in the range of 0.04 to 0.07% by mass.Öğe The new metal complex templated polyoxoborate(s) (POB(s)) structures. Synthesis, structural characterization, and hydrogen storage capacities(Elsevier B.V., 2017) Köse, Dursun Ali; Yurdakul, Ömer; Şahin, Ozan; Öztürk, ZeynelThe polyoxoborate(s) (POB(s)) structures, including a neutral ligand-metal complex compound as a template, were synthesized and the structural characterizations were performed via single crystal X-ray diffraction, FTIR, 11B-NMR, solid state UV–Vis spectroscopy, SEM and elemental analysis methods. Moreover, the stabilization features were determined via TGA/DTA method. In addition, nitrogen and hydrogen adsorption measurements provided the realization to determine the pore size distribution, BET surface area, and hydrogen storage capacities. The molecular formulas of compounds were estimated as [Cu(C12H8N2)2(C2H3O2)][B5O6(OH)4]·2H3BO3·H2O (I) and [Ni(C12H8N2)2(H2O)2]·(B7O9(OH)5)·5H2O (II) and the existence of two different POB(s) structures as pentaborate (B5O6(OH)4) and heptaborate (B7O9(OH)5) within the compounds were observed. At last, it was found that the both structures have micro and mesoporosity with 0.407 and 1.480 m2/g BET surface areas, for the compound I and II, respectively. Moreover, within the same conditions, compound II could uptake 0.19 wt% hydrogen at 77 K and at the relative pressure of 1 while compound II uptakes 0.035 wt% hydrogen. © 2017 Elsevier B.V.Öğe The structural and thermal characterization of new Cu-Arginate complex; experimental and simulated hydrogen adsorbstion properties(Hitit University, 2016) Şahin, Zarife Sibel; Öztürk, Zeynel; Yurdakul, Ömer; Köse, Dursun AliThe copper-arginate complex was synthesized and characterized by using FTIR, TG/DTA-DrTG, UV-Vis spectroscopy and elemental analysis methods. In addition, experimental and theoretical hydrogen storage capabilities were investigated. The unit cell of complex structure included that one mole CuII as centered cation and one mole of free NaI cation and one mole of NaSO4- as coordinated to arginine ligand and two moles of arginate ligands and one mole of aqua ligand as coordinated to NaSO4-. The CuII cation had square-pyramidal coordination sphere and the Na1 metal cation had trigonal coordination scheme. The other sodium metal cation (Na2) was implemented in the released position as counter ion of NaSO4-. It was found that the arginine complex, synthesized in this work have 0.533 m2/g BET surface area and 6.92E-3 wt. % hydrogen storage capacity at 77 K and 1 bar while simulated value was 3.27E-3 wt. % for the same conditions.Öğe Toprak alkali metallerin asesülfam ve asesülfam-nikotinamid karışık ligand komplekslerinin sentezi, yapısal karakterizasyonu ve çeşitli biyolojik uygulamaları(Hitit Üniversitesi Fen Bilimleri Enstitüsü, 2013) Yurdakul, Ömer; Köse, Dursun AliBu tez çalışması kapsamında, Mg(II), Ca(II), Sr(II) ve Ba(II) metallerinin ilk defa asesülfam (ace, acs) ve asesülfam-nikotiamide (na) karışık ligand kompleksleri sentezlenmiştir ([Mg(H2O)6](acs)2, C8H10CaN2O9S2, C8H10SrN2O9S2, C8H10BaN2O9S2, [Mg(H2O)4(na)2](acs)2, [Ca(H2O)6(na)2](acs)2, [Sr(H2O)7(na)2](acs)2, [Ba(H2O)7(na)2](acs)2). Sentezlenen kompleksler erime noktası, elementel analiz, kütle spektroskopisi, FT-IR spektroskopisi ve uygun kristaller ayrılarak X-ışınları tek kristal kırınım yöntemleri ile karakterize edilmiştir. Komplekslerin termal özellikleri ise eş zamanlı TG-DTG ve DTA teknikleriyle aydınlatılmıştır. Geçiş metallerine karşı koordinasyon davranışı literatürde var olan, imin azotu, karbonil oksijeni, sülfonil oksijenleri ve halka oksijeni gibi verici atomlara sahip olan asesülfamat ligandının toprak alkali metallere karşı koordinasyon davranışları belirlenmiştir. Asesülfam-metal komplekslerinin yapısal çalışmaları için önemli olan karakteristik ?(OH), ?(C=O), ? as(SO2) ve ?s(SO2) titreşimleri belirlenmiştir. Komplekslerin yapıları X-ışınları tek kristal kırınımı yöntemiyle aydınlatılmıştır. Asesülfamat iyonunun Mg(II) kompleksinde tamamlayıcı iyon olarak davranmaktadır. Ca(II), Sr(II) ve Ba(II) komplekslerinde ise asesülfamat iyonunun çok dişli ligand olarak koordinasyona katıldığı belirlendi. Bu komplekslerin polimerik yapıya sahip olduğu anlaşılmıştır. Ayrıca sentezlenen komplekslerin biyolojik aktivitesi incelenmiştir. Bu çalışma için Escherichia coli , Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis bakteri türleri ve Candida albicans mantar türü kullanılmıştır. Fakat komplekslerin antimikrobiyal özellik göstermediği tespit edilmiştir.Öğe Two novel mixed-ligand zinc-acesulfame compounds: Synthesis, spectroscopic and thermal characterization and biological applications(Elsevier B.V., 2020) Yurdakul, Ömer; Köse, Dursun Ali; Şahin, Onur; Alp Avcı, GülçinTwo new tetrahedral acesulfame complexes, acesulfamato(N)acesulfamato(O)bis(3-aminopyridine) zinc(II) (C18H20N6O8S2Zn, Zn-ace-3ap) and bis(acesulfamato-O)bis(benzotriazole)zinc(II) (C20H18N8O8S2Zn, Zn-ace-bta), were synthesized and characterized by single crystal X-ray diffraction, FT-IR spectroscopy, elemental analysis and thermal analysis techniques(TGA, DTA, DTG). The first compound, Zn-ace-3ap, crystallizes in triclinic space group P1 with parameters a?=?7.978 (7) Å, b?=?9.907 (6) Å, c?=?15.778 (14) Å, ??=?78.24° (2), ??=?81.22° (4), ??=?75.99° (2), Z?=?2 and The second compound, Zn-ace-bta, crystallizes in monoclinic space group C2/c with parameters a?=?19.879 (3) Å, b?=?9.3637 (13) Å, c?=?14.0852 (18) Å, ??=?105.483° (4), Z?=?4. The biological activities of the synthesized complexes were appraised through disk diffusion method as antibacterial, antimicrobial and antifungal in DMSO. Enterococcus faecalis (ATCC-29212), Staphylococcus aureus (ATCC-25923) as gram-positive bacteria, Pseudomonas aeroginosa (ATCC-27853) and Escherichia coli (ATCC-25922) as gram-negative bacteria, and Candida albicans (ATCC-10231) as fungus were grown with a view to investigate the antimicrobial effects of the complexes.Öğe Zwitterionic amino acids as precursors for nonmetal cation pentaborate salts(Wiley-V C H Verlag Gmbh, 2020) Sızır, Umit; Yurdakul, Ömer; Köse, Dursun Ali; İçten, OkanNonmetal cation (NMC) pentaborate structures were synthesized using the amino acid molecules as cations precursors. Chemical composition analysis, infrared spectroscopy, mass analysis, boron nuclear magnetic resonance, and thermal gravimetric analysis (TGA/DTA) methods were used for structural characterization. The hydrogen storage efficiency of molecules was also determined experimentally. The recorded infrared spectra support the structural similarities of the molecules. Stretchings of pentaborate rings and characteristic peaks of amino acids were detected in infrared spectra. When the thermal analysis curves were recorded, it was found that the structures showed similar decomposition steps. Due to the result of thermal decay, glassy boron oxide (B2O3) formation was observed as the final decomposition products of all molecules. Peaks associated with boric acid, triborate, and pentaborate were observed in the B-11 spectra of these salts. Powder X-ray diffraction spectroscopy supports the presence of BO3 and BO4- groups regarding the presence of pentaborate rings. It also indicates the high crystallinity of the structures. The molecular cavities detected by brunauer-emmett-teller analysis were found to be 3.586, 1.922, 1.673, and 1.923 g/cm(3). Low-molecular cavities can be attributed to the high hydrogen-bonding capacity of the structures. The hydrogen capture efficiency of the pentaborate salts was found to be in the range of 0.039-0.
