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Öğe Catechol-type ligand containing new modular design dioxaborinane compounds: Use in the transfer hydrogenation of various ketones(Elsevier Science Bv, 2018) Kilic, Ahmet; Kaya, Ibrahim Halil; Ozaslan, Ismail; Aydemir, Murat; Durap, FeyyazA novel class of tricoordinate dioxaborinane compounds, which have the general formula [B-1(L1-5)] and [B-2(L1-5)], were designed and synthesized by the corresponding catechol-type ligands (L-1-L-5) at ambient temperature. All the new compounds were fully characterized by NMR (H-1, C-13, and B-11), FT-IR, UV-vis, LC-MS spectroscopy, and melting point analysis and microanalysis. The dioxaborinane [B-1(L1-5)] and [B-2(L1-5)] compounds were investigated as catalyst for the transfer hydrogenation of various ketones under suitable conditions. Particularly, it was proved that the ferrocene-based dioxaborinane [B-1(L1-5)] molecules can afford an efficient catalytic conversion compared to corresponding 3,5-bis(trifluoromethyl)phenyl-based [B-2(L1-5)] dioxaborinanes in transfer hydrogenation catalytic studies.Öğe The chiral boronate-catalyzed asymmetric transfer hydrogenation of various aromatic ketones to high-value alcohols: Preparation and spectroscopic studies(Elsevier Science Sa, 2019) Kilic, Ahmet; Durgun, Mustafa; Durap, Feyyaz; Aydemir, MuratThis work deals with the synthesis, spectroscopic studies and catalytic evaluation of the novel chiral salen (L1H2) and (L2H2) ligands and their chiral boronate [L-1(B1-4)] and [L-2(B1-4)] complexes. Initially, the reaction of 5-azidomethyl salicylaldehyde and (R)-(-)-2-amino-1-butanol in absolute ethanol afforded a new chiral salen ligand (L1H2). Then, a novel chiral salen ligand (L2H2) have been prepared from chiral salen ligand (L1H2) for the synthesis of boronate [L-2(B1-4)] complexes through click reaction approach under ambient conditions. The reaction of chiral salen (L1H2) and (L2H2) ligands with various boronic acids afforded a new tetra-coordinated mononuclear chiral boronate [L-1(B1-4)] and [L-2(B1-4)] complexes. All the compounds are remarkably stable crystalline solids and were obtained in good yields. For the full characterization of newly synthesized chiral salen ligands and their boronate complexes, the FT-IR, UV-Vis, NMR (H-1, C-13, and B-11), LC-MS, and elemental analysis techniques have been used. The well-shaped chiral boronate compounds were investigated as catalyst for the asymmetric transfer hydrogenation (ATH) of aromatic ketones under appropriate settings. Particularly, it was proved that the ferrocene-based boronate compounds can afford an efficient catalytic conversion compared to the other boronate complexes in the asymmetric transfer hydrogenation catalytic studies. (C) 2019 Elsevier B.V. All rights reserved.Öğe Different Hemi-Salen/Salan Ligand Containing Binuclear Boron-Fluoride Complexes: Synthesis, Spectroscopy, Fluorescence Properties, and Catalysis(Taylor & Francis Ltd, 2019) Kilic, Ahmet; Ozbahceci, Orcun; Durgun, Mustafa; Aydemir, MuratA family of hemi-salen (L1H-L6H) and hemi-salan (L1aH-L2aH) ligands-based N,O-chelated binuclear boron-fluoride [L-n(BF2)(2)] (n = L-1-L-6 or L-1a-L-2a) complexes have been prepared and characterized by a variety of spectroscopic techniques (H-1, C-13 and F-19 NMR, FT-IR, UV-Vis, LC-MS, and fluorescence spectra) and elemental analysis. All of the binuclear boron-fluoride complexes exhibit strong absorption bands due to S-0 -> S-1 transitions and strong fluorescence properties were observed at room temperature in the solution. The binuclear boron complexes containing two naphthyl groups are significantly red-shifted in comparison with the other binuclear boron-fluoride complexes. After the structures are characterized, these hemi-salen and salan ligand-based N, O-chelated binuclear boron-fluoride complexes were utilized to the transfer hydrogenation of the different acetophenone derivatives conversion to 1-phenylethanol derivatives as catalysts.Öğe Fluorine/phenyl chelated boron complexes: Synthesis, fluorescence properties and catalyst for transfer hydrogenation of aromatic ketones(Elsevier Science Sa, 2014) Kilic, Ahmet; Aydemir, Murat; Durgun, Mustafa; Meric, Nermin; Ocak, Yusuf Selim; Keles, Armagan; Temel, HamdiThe synthesis of salen/salan ligands (L-1 and L-2) and their fluorine/phenyl chelated boron complexes [L(1,2)BF2] or [L(1,2)BPh2] is described in this paper. The fluorine/phenyl chelated boron complexes were synthesized from the reaction of BF3 center dot OEt2 or BPh3 with the corresponding ligands in different solvent. The boron complexes display high stability and can be handled in air due to the presence of coordinative B <- N and covalent B-O bonds in their structures. The salen/salan ligands (designated as salan, a saturated version of the corresponding salen ligands) and their fluorine/phenyl chelated boron complexes have been characterized by H-1, C-13 NMR and F-19 NMR spectra, elemental analysis, FT-IR spectra, UV-vis spectra, LC-MS spectra, melting point and fluorescence spectroscopy. The fluorescence efficiencies of BF2-chelate boron complexes are greatly improved compared to those of the BPh2-chelate boron analogs based on the same salen/salan ligands, probably due to the enhanced conjugation degree of the diphenyl boron chelation, which can effectively prevent molecular aggregation. The boron complexes [L(1,2)BF2] or [L(1,2)BPh2] were also applied to the transfer hydrogenation of aromatic ketones to the corresponding alcohol derivatives in the presence of iso-PrOH as the hydrogen source. Catalytic studies showed that all complexes are good catalytic precursors for transfer hydrogenation of aryl alkyl ketones in 0.1 M iso-PrOH solution. This transfer hydrogenation is characterized by low reversibility under these conditions. (C) 2014 Elsevier B.V. All rights reserved.Öğe Pd(II) supported dioxime functionalized Fe3O4 nanoparticles as efficient, eco-friendly and reusable catalysts for the Suzuki-Miyaura cross-coupling reaction in water(Elsevier Science Sa, 2019) Kilic, Ahmet; Gezer, Esra; Durap, Feyyaz; Aydemir, Murat; Baysal, AkinFive novel dioxime ligands (L(1-5)H2) were synthesized in various yields under suitable conditions. Novel nano-Fe3O4-supported compounds (Fe3O4/L(1-5)) based on dioxime ligands were also prepared. Subsequently, hybrid materials Fe3O4/L(1-5)/Pd(II) were fabricated by the reaction of Fe3O4/L(1-5) with Pd(AcO)(2) in acetonitrile. All synthesized nanoparticles were characterized by FT-IR spectroscopy, scanning electron microscopy (SEM), energy dispersive X-Ray analysis (EDX), X-ray diffraction (XRD), inductively coupled plasma analysis (ICP), differential scanning calorimetry (DTA), and thermogravimetric analysis (TGA). The spectroscopic results show that the magnetite (Fe3O4) nanoparticles are in nano size since crystal sizes are < 100 nm. The particles have an average size of about 9.4-23.3 nm. The powder XRD confirmed that the synthesized Fe3O4, Fe3O4/L(1-5), and Fe3O4/L(1-5)/Pd(II) MNPs possess cubic structure having the lattice parameter between 8.31 and 8.40 A. The structure and the lattice parameters are in good agreement with the literature reported data. The Fe3O4/L(1-5)/Pd(II) nanocatalysts showed high activities in the Suzuki-Miyaura cross-coupling of different aryl halides including iodides, bromides and even chlorides with phenylboronic acid under green and aerobic conditions. More importantly, the reusability experiments revealed that Fe3O4/L(1-5)/Pd(II) catalysts were durable by almost maintaining their inherent activity after 5 catalytic cycles. (c) 2019 Elsevier B.V. All rights reserved.Öğe Preparation, characterisation and redox properties of four new tetradentate salicylaldimines with their Cu(II) complexes(Sage Publications Ltd, 2006) Tas, Esref; Aslanoglu, Mehmet; Kilic, Ahmet; Kaplan, Omer; Temel, HamdiSome new tetradentate salicylaldimine ligands of Schiff bases were synthesised by treating 3,5-di-tertbutyl-2-hydroxybenzaldehyde with 1,2-bis-(o-aminophenoxy)ethane, 1,4-bis-(o-aminophenoxy)butane, 1,4-bis(m-aminophenoxy)buthane and 1,4-bis-(p-aminophenoxy)butane. The compounds were characterised by IR, UV-vis, H-1 NMR, C-13 NMR, magnetic susceptibility measurements, elemental analysis, molar conductance (Am), thermogravimetric analysis (TGA) and cyclic voltammetry. The metal to ligand ratios of the Cu(II) complexes were found to be 1:1. The coordination of the novel tetradentate salicylaldimines appears to occur through the two azomethine nitrogens and two o-OH groups. Cyclic voltammetric studies showed that all of the C(II) complexes undergo quasi reversible one-electron transfer redox processes attributed the Cu(II)/Cu(I) couples in dimethylsufoxide. The electron donor affinity of copper(II) complexes increases in order Cu(L-4)>Cu(L-3)>Cu(L-2)>Cu(L-1).Öğe The properties of the new Mn(II)-Co(II)-Mn(II)-type hetero-trinuclear oxime metal complexes with N4 and N4O2 ligands(Springer, 2010) Kilic, Ahmet; Durap, Feyyaz; Baysal, Akin; Durgun, MustafaThe novel one N-4 and two N4O2 containing hetero-trinuclear oxime metal complexes, [Co(L)(2)(H2O)(2)Mn-2(dafo)(4)](ClO4)(2) (1), [Co(L)(2)(H2O)(2)Mn-2(dafdione)(4)](ClO4)(2) (2), [Co(L)(2)(H2O)(2)Mn-2(dcbpy)(4)](ClO4)(2) (3) and [Co(L)(2)(H2O)(2)Mn-2(phen)(4)](ClO4)(2) (4), (where, L = N,N'-bis(ethyl-4-amino-1-piperidine carboxylate)-glyoxime, dafo = 4,5-diazafluoren-9-one, dafdione = 1H-cyclopenta[1,2-b:5,4-b']dipyridine-2,5-dione, dcbpy = 3,3'-dicarboxy-2,2'-bipyridine and phen = 1,10-phenanthroline) have been synthesized and characterized by UV-Vis, FT-IR spectra, magnetic susceptibility measurements, molar conductivity, X-ray powder techniques, mass spectra and their morphology studied by SEM measurements. The H-bonding (O-H center dot center dot center dot O) in the Mn(II)-Co(II)-Mn(II)-type hetero-trinuclear oxime metal complexes disappears, the Co(II) ion centered into the main oxime core by the coordination of the imino groups while the two Mn(II) ions coordinated to dianionic oxygen donors of the oxime groups and linked to the ligands of dafo, dafdione, dcbpy and phen.Öğe Ru(II) with chelating containing N4-type donor quadridentate Pd-oxime metal complexes(Elsevier Science Sa, 2008) Kilic, Ahmet; Durap, Feyyaz; Aydemir, Murat; Baysal, Akin; Tas, EsrefFive new metal complexes [ Pd( LH) 2] ( 1), [ Pd( L) 2Ru2( bpy) 4]( ClO4) 2 ( 2), [ Pd( L) 2Ru2( phen) 4]( ClO4) 2 ( 3), [ Pd( L) 2Ru2( dafo) 4]( ClO4) 2 ( 4) and [ Pd( L) 2Ru2( dcbpy) 4]( ClO4) 2 ( 5), ( where, L = ligand, bpy = 2,20- bipyridine, phen = 1,10- phenantroline, dafo = 4,5- diaza. uoren- 9- one and dcbpy = 3,30- dicarboxy- 2,20- bipyridine) have been isolated and characterized by UV - VIS, FT- IR, 1H NMR, magnetic susceptibility measurements, elemental analysis, molar conductivity, X- ray powder techniques, thermal analyses and their morphology studied by SEM measurements. IR spectra show that the ligand acts in a tetradentate manner and coordinates N4 donor groups of LH2 to PdII ion. The disappereance of H- bonding ( O-H center dot center dot center dot O) in the trinuclear RuII - PdII - RuII metal complexes, the RuII ion centered into the main oxime core by the coordination of the imino groups while the two RuII ions coordinate dianionic oxygen donors of the oxime groups and linked to the ligands of bpy, phen, dafo and dbpy. The X- powder results show that 1 metal complex is indicating crystalline nature, not amorphous nature. Whereas, the X- ray powder pattern of the ligand ( LH2) with 2, 3, 4 and 5 exhibited only broad humps, indicating its amorphous nature. The catalytic activity of three different complexes were tested in the Suzuki coupling reaction. The 1, 4 and 5 metal complexes catalyse Suzuki coupling reaction between phenylboronic acid and arylbromides affording biphenyls. Also, the thermal results shown that the most stable complex is 1 compound while the less stable is 4 compound. (c) 2008 Elsevier B. V. All rights reserved.Öğe Synthesis and spectral characterization of macrocyclic NiII complexes derived from various diamines, NiII perchlorate and 1,4-bis(2-carboxyaldehydephenoxy)butane(Springer, 2007) Ilhan, Salih; Temel, Hamdi; Kilic, Ahmet; Tas, EsrefSix new macrocyclic complexes were synthesized by reaction of 1,4-bis(2-carboxyaldehyde phenoxy)butane with various diamines. Then, their nickel(II) perchlorate complexes were synthesized by the template effect by reaction of 1,4-bis(2-carboxyaldehyde phenoxy)butane, Ni(ClO4)(2) center dot 6H(2)O and various diamines. The metal-to-ligand ratio of Ni-II metal complexes was found to be 1:1. The compounds are coordinated to the central metal as tetradentate O2N2 ligands The Ni-II complexes are proposed to exhibit tetrahedral geometry. Ni-II metal complexes are 1:2 electrolytes as shown by their molar conductivities (Lambda(M)) in DMF (dimethyl formamide) at 10(-3) M. The structure of Ni-II metal complexes is proposed from elemental analysis, f.t.-i.r., u.v.-vis., magnetic susceptibility measurements, molar conductivity measurements and mass spectra.Öğe Synthesis and spectral studies of macrocyclic Cu(II) complexes by reaction of various diamines, copper(II) perchlorate and 1,4-bis(2-carboxyaldehyde phenoxy)butane(Taylor & Francis Ltd, 2008) Ilhan, Salih; Temel, Hamdi; Kilic, AhmetSix macrocyclic complexes, were synthesized by reaction of 1,4-bis(2-carboxyaldehyde phenoxy)butane and various amines and their copper(II) perchlorate complexes were synthesized by template effect reaction of 1,4-bis(2-carboxyaldehyde phenoxy)butane, Cu(ClO4)2 center dot 6H(2)O and amines. The metal-to-ligand ratios were found to be 1 : 1. Cu(II) metal complexes are 1: 2 electrolytes as shown by their molar conductivities (Lambda(M)) in DM F (dimethyl formamide) at 10(-3) M. The Cu(II) complexes are proposed to be square planar based on elemental analysis, FT-IR, UV-Vis, magnetic susceptibility measurements, molar conductivity measurements, and mass spectra.Öğe Synthesis, characterization and electro-spectroelectrochemical studies of four macrocyclic Schiff-base Co(II) complexes having N2O2 set of donor atoms(Springer, 2009) Yilmaz, Ismail; Ilhan, Salih; Temel, Hamdi; Kilic, AhmetFour macrocyclic Schiff-base cobalt complexes, [CoL1][NO3](2) center dot A 3H(2)O, [CoL2][NO3](2) center dot A 4H(2)O, [CoL3][NO3](2) center dot A 4H(2)O and [CoL4][NO3](2) center dot A 2H(2)O, were synthesized by reaction of salicylaldehyde derivatives with 1,4-bis(3-aminopropoxy)butane or (+/-)-trans-1,2-diaminocyclohexane and Co(NO3)(2) center dot A 6H(2)O by template effect in methanol. The metals to ligand ratio of the complexes were found to be 1:1. The Co(II) complexes are proposed to be tetrahedral geometry. The macrocyclic Co(II) complexes are 1:2 electrolytes as shown by their molar conductivities (I >(M)) in DMF (dimethyl formamide) at 10(-3) M. The structure of Co(II) complexes is proposed from elemental analysis, Ft-IR, UV-visible spectra, magnetic susceptibility, molar conductivity measurements and mass spectra. Electrochemical and thin-layer spectroelectrochemical studies of the complexes were comparatively studied in the same experimental conditions. The electrochemical results revealed that all complexes displayed irreversible one reduction processes and their cathodic peak potential values (E (pc)) were observed in around of -1.14 to 0.95 V. It was also seen that [CoL1][NO3](2) center dot A 3H(2)O and [CoL2][NO3](2) center dot A 4H(2)O exhibited one cathodic wave without corresponding anodic wave but, [CoL3][NO3](2) center dot A 4H(2)O and [CoL4][NO3](2) center dot A 2H(2)O showed one cathodic wave with corresponding anodic wave, probably due to the presence of different ligand nature even if the complexes have the same N2O2 donor set. In view of spectroelectrochemical studies [CoL3][NO3](2) center dot A 4H(2)O showed distinctive spectral changes in which the intensity of the band (lambda A = at 316 nm, assigned to n -> pi* transitions) decreased and a new broad band in a low intensity about 391 nm appeared as a result of the reduction process based on the cobalt center in the complex.Öğe Synthesis, characterization and redox properties of macrocyclic Schiff base by reaction of 2,6-diaminopyridine and 1,3-bis(2-carboxyaldehyde phenoxy) propane and its CuII, NiII, PbII, CoIII and LaIII complexes(Springer, 2007) Ilhan, Salih; Temel, Hamdi; Yilmaz, Ismail; Kilic, AhmetA new macrocyclic ligand, 1,3,5-triaza-2,4:7,8:, 14,15-tribenzo-9,13-dioxacyclohexadeca-1,5-diene ( L) was synthesized by reaction of 2,6-diaminopyridine and 1,3-bis(2-carboxyaldehyde phenoxy) propane. Then, its Cu-II, Ni-II, Pb-II, Co-III and La-III complexes were synthesized by a template effect by reaction of 2,6-diaminopyridine and 1,3-bis (2-carboxyaldehyde phenoxy) propane and Cu(NO3)(2) center dot 3H(2)O, Ni(NO3)(2) center dot 6H(2)O, Co(NO3)(2) center dot 6H(2)O, La(NO3)(3) center dot 6H(2)O, respectively. The ligand and its metal complexes have been characterized by elemental analysis, IR, H-1- and C-13-NMR-, UV-vis spectra, magnetic susceptibility, conductivity measurements, mass spectra and cyclic voltammetry. All complexes are diamagnetic and the Cu-II complex is binuclear. The diamagnetic behaviour of the binuclear complex may be explained by a very strong anti-ferromagnetic interaction in the Cu-Cu pair. The Co-II was oxidised to Co-III.Öğe Synthesis, spectral characterization and electrochemical properties of new vic-dioxime complexes bearing carboxylate(Springer, 2006) Kilic, Ahmet; Tas, Esref; Gumgum, Bahattin; Yilmaz, IsmailThree new vic-dioxime ligands, [N-(ethyl-4-amino-1-piperidine carboxylate)-phenylglyoxime ((LH2)-H-1), N-(ethyl-4-amino-1-piperidine carboxylate)-glyoxime (L(2)pH(2)), and N,N'-bis(ethyl-4-amino-1-piperidine carboxylate)-glyoxime ((LH2)-H-3)], and their Co(II) with Cu(II) metal complexes, were synthesized for the first time. Mononuclear complexes of these ligands with a 1:2 metal-ligand ratio were prepared with Co(II) and Cu(II) salts. The BF2+-capped Co(II) and mononuclear complexes of the vic-dioxime were prepared for [Co(L-1 center dot BF2)(2)] and [Co(L-2 center dot BF2)(2)]. The ligands act in a polydentate fashion bonding through nitrogen atoms in the presence of a base, as do most vic-dioximes. The cobalt(II) and copper(II) complexes are non-electrolytes as shown by their molar conductivities (Lambda(M)) in DMF. The structures of the ligands and complexes were determined by elemental analyses, FT-i.r., u.v.-vis., H-1- and C-13-n.m.r. spectra, magnetic susceptibility measurements, and molar conductivity. The comparative electrochemical studies show that the stabilities of the reduced or oxidized species and the electrode potentials of the complexes are affected by the substituents attached on the oxime moieties of the complexes.Öğe Synthesis, spectroscopic and catalytic properties of some new boron hybrid molecule derivatives by BF2 and BPh2 chelation(Pergamon-Elsevier Science Ltd, 2015) Kilic, Ahmet; Alcay, Ferhat; Aydemir, Murat; Durgun, Mustafa; Keles, Armagan; Baysal, AkinA new series of Schiff base ligands (L-1-L-3) and their corresponding fluorine/phenyl boron hybrid complexes [LnBF2] and [LnPh2] (n=1, 2 or 3) have been synthesized and well characterized by both analytical and spectroscopic methods. The Schiff base ligands and their corresponding fluorine/phenyl boron hybrid complexes have been characterized by NMR (H-1, C-13 and F-19), FT-IR, UV-Vis, LC-MS, and fluorescence spectroscopy as well as melting point and elemental analysis. The fluorescence efficiencies of phenyl chelate complexes are greatly red-shifted compared to those of the fluorine chelate analogs based on the same ligands, presumably due to the large steric hindrance and hard pi ->pi* transition of the diphenyl boron chelation, which can effectively prevent molecular aggregation. The boron hybrid complexes were applied to the transfer hydrogenation of acetophenone derivatives to 1-phenylethanol derivatives in the presence of 2-propanol as the hydrogen source. The catalytic studies showed that boron hybrid complexes are good catalytic precursors for transfer hydrogenation of aromatic ketones in 0.1 M iso-PrOH solution. Also, we have found that both steric and electronic factors have a significant impact on the catalytic properties of this class of molecules. (C) 2015 Elsevier B.V. All rights reserved.Öğe The synthesis, spectroscopic and voltametric studies of new metal complexes containing three different vic-dioximes(Taylor & Francis Ltd, 2007) Kilic, Ahmet; Tas, Esref; Gumgum, Bahattin; Yilmaz, IsmailThe synthesis, spectroscopic, and redox properties of some metal complexes with three novel vic-dioxime ligands, N-(1-(2-aminoethyl) piperazine)-phenylglyoxime (L1H2), N-(1-(2-aminoethyl) piperazine)-glyoxime (L2H2), and N, N'-bis(1-(2-aminoethyl) piperazine)-glyoxime (L3H2)], prepared from different glyoxime and 1-(2-aminoethyl) piperazine are reported. The structure of these vic-dioximes have been determined as the anti-form according to H-1 NMR, C-13 NMR, and FT-IR data. The metal to ligand ratios of Co(II), Ni(II), and Cu(II) complexes were found to be 1:2. The Cu(II) complexes of these ligands are proposed to be square planar and Ni(II) complexes of these ligands are proposed to be square planar or octahedral, while the Co(II) complexes are proposed to be octahedral with water molecules as axial ligands. Ni(II), Co(II), and Cu(II) metal complexes are non-electrolytes as shown by their molar conductivities (Lambda(M)) in DMF (dimethyl formamide) at 10(-3) M. The structure of ligands and their complexes is proposed from elemental analysis, FT-IR, UV-VIS, H-1 NMR, C-13 NMR, magnetic susceptibility measurements, and molar conductivity measurements. The cyclic voltammetric measurements of the mononuclear complexes provide an understanding of the electrochemical behaviour of the reduced or oxidized species in DMSO solution.
