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Öğe 5-(3,6-Dibromo-9H-carbazol-9-yl)pentanenitrile(Wiley-Blackwell, 2011) Uludağ, Nesimi; Ateş, Murat; Tercan, Barış; Hökelek, TuncerIn the title compound, C17H14Br2N2, the carbazole skeleton is nearly planar [maximum deviation = 0.055 (2) angstrom]. In the crystal, aromatic pi-pi stacking is observed between parallel carbazole ring systems of adjacent molecules, the shortest centroid-centroid distance between benzene rings being 3.4769 (11) angstrom.Öğe 9-(4-Nitrophenylsulfonyl)-9H-carbazole(Wiley-Blackwell, 2011) Uludağ, Nesimi; Ateş, Murat; Tercan, Barış; Hökelek, TuncerIn the title molecule, C18H12N2O4S, the carbazole skeleton is nearly planar [maximum deviation = 0.037 (1) A] and is oriented at a dihedral angle of 73.73 (5)degrees with respect to the benzene ring. An intramolecular C-H...O hydrogen bond links a nitro O atom to the carbazole skeleton. In the crystal, intermolecular C-H...O hydrogen bonds link the molecules into a three-dimensional network. pi-pi contacts between inversion-related benzene rings [centroid-centroid distance = 3.7828 (8) A] and two weak C-H...pi interactions may also stabilize the structure.Öğe 9-Benzyl-9H-carbazole(Wiley-Blackwell, 2010) Uludağ, Nesimi; Ateş, Murat; Tercan, Barış; Ermiş, Emel; Hökelek, TuncerThe asymmetric unit of the title compound, C(19)H(15)N, contains two crystallographically independent molecules. In both molecules, the planar carbazole moieties [maximum deviations = 0.037 (4) and 0.042 (3) angstrom] are oriented with respect to the adjacent benzene rings, at dihedral angles of 85.29 (8) and 89.89 (7)degrees, respectively. In the crystal structure, weak C-H center dot center dot center dot pi interactions are observed involving the carbazole rings.Öğe 9H-Carbazole-9-carbothioic dithioperoxyanhydride(Int Union Crystallography, 2013) Uludağ, Nesimi; Ateş, Murat; Çaylak Delibaş, Nagihan; Çelik, Ömer; Hökelek, TuncerThe whole molecule of the title compound, C26H16N2S4, is generated by twofold rotational symmetry. The carbazole skeleton is nearly planar [maximum deviation = 0.054 (5)angstrom]. In the crystal, aromatic pi-pi stacking is observed between parallel carbazole ring systems of adjacent molecules, the shortest centroid-centroid distances between pyrrole and benzene rings being 3.948 (3) and 3.751 (3) angstrom.Öğe A Concise Total Synthesis of Deethylaspidospermidine(Taylor & Francis Inc, 2019) Uludağ, Nesimi[No Abstract Available]Öğe A DFT Investigation on the Structure, Spectroscopy (FT-IR and NMR), Donor-Acceptor Interactions and Non-Linear Optic Properties of (+/-)-1,2-Dehydroaspidospermidine(Wiley-V C H Verlag Gmbh, 2019) Uludağ, Nesimi; Serdaroğlu, GoncagülIn this study, (+/-)-1,2-Dehydroaspidospermidine was analyzed by elemental analysis, H-1 and C-13 NMR, and FT-IR spectra. Also, because the starting geometry is essential to evaluate the structural, electronic, and spectral properties of this compound, we used the potential energy surface (PES) scan by the B3LYP/6-31G(d,p) hybrid functional to determine the stable structures of the (+/-)-1,2-Dehydroaspidospermidine. Thus, three stable conformations of the compound were used in all of the electronic and spectroscopic simulations performed by the M06-2X, G96LYP, and B3LYP functionals at the 6-311++G(d,p) basis set in a vacuum and chloroform. After the observed and simulated FT-IR and NMR data were compared, the second order perturbative theory in the NBO (Natural Bond Orbital) basis was used to interpret the critical donor-acceptor interactions; the dominant contribution to the lowering of the second order energy for all conformers was the pi -> pi* and sigma -> pi* interactions. Also, we used both NLO (Non Linear Optic) and FMO (Frontier Molecular Orbital) analyses to investigate the non-linear optical property and the biochemical reactivity of the compound. The results of this work demonstrated that the compound has an available non-linear optical property (beta=6.62 x 10(-30) esu) that can be used in optoelectronic technology, and, besides, it has biological activity because of its strong intramolecular interactions.Öğe A Facile and Convenient Synthesis of (+/-)-Dasycarpidone(Springer, 2020) Uludağ, NesimiAn efficient new pathway for (+/-)-dasycarpidone has been synthesized. The most important step in the synthesis of (+/-)-dasycarpidone is the intramolecular cyclization of the azocino[4,3-b]indole skeleton, which is constructed via tetrafluoro-1,4-benzoquinone and tetrachloro-1,4-benzoquinone and a mediated dehydrogenative cyclization of a tetrahydrocarbazole derivative possessing an amide side chain and is accomplished with high yield. The structures of all the presently synthesized compounds were confirmed using spectroscopic methods (FT-IR, H-1 NMR, C-13 NMR).Öğe A new approach to the total synthesis of (±)-nordasycarpidone by ring-closure with tetrachloro-1,4-benzoquinone(Macedonian Journal of Chemistry and Chemical Engineering, 2020) Uludağ, Nesiminew synthetic route for the (±)-nordasycarpidone was achieved in five steps with an overall yield of 41 %. This route involves ring closure and formation of 5 which has a methanoazocino[4,3-b]indole skeleton in the key step. The reaction also involved a cyclization reaction of tetrahydrocarbazole with a monoalkyl nitrile side chain at the C-2 position, and this reaction was mediated by tetrachloro-1,4-benzoquinone (TCB). The central step in the synthesis was the closure of the D-ring of the intra-molecu-lar structure and the addition of amine, which resulted in an aza-tetracyclic substructure that contained the ABCD-ring of the strychnos alkaloid family. © 2020, Macedonian Journal of Chemistry and Chemical Engineering.Öğe A New Approach to the Total Synthesis of 20-Deethyltubifolidine and an Entry to the Azocino[4,3-b]indoles(Taylor & Francis Inc, 2020) Uludağ, Nesimi; Duran, Ebru[No Abstract Available]Öğe A NEW REAGENT FOR EFFICIENT SYNTHESIS OF NITRILES FROM ALDOXIMES USING METHOXYMETHYL BROMIDE(Editura Acad Romane, 2019) Uludağ, Nesimi; Nur Giden, ÖzgeThis study outlines an efficient, high-yielding, and rapid method by which to access diverse nitriles from aldoximes with methoxymethyl bromide (MOM-Br) in THF. It represents the first application of MOM-Br as a deoximation reagent to synthesize nitriles. The reaction was performed at reflux to ensure excellent yield (79-96%) of the nitriles within 20-45 minutes. Furthermore, this method has been successfully applied to the synthesis of the synthesis precursor of aromatic, heteroaromatic, cyclic, and acyclic aliphatic.Öğe A new reagent for efficient synthesis of nitriles from aldoximes using methoxymethyl bromide(Editura Academiei Romane, 2021) Uludağ, Nesimi; Nur Giden, ÖzgeThis study outlines an efficient, high-yielding, and rapid method by which to access diverse nitriles from aldoximes with methoxymethyl bromide (MOM-Br) in THF. It represents the first application of MOM-Br as a deoximation reagent to synthesize nitriles. The reaction was performed at reflux to ensure excellent yield (79-96%) of the nitriles within 20-45 minutes. Furthermore, this method has been successfully applied to the synthesis of the synthesis precursor of aromatic, heteroaromatic, cyclic, and acyclic aliphatic. © 2019 Editura Academiei Romane. All rights reserved.Öğe A novel synthesis of (3,6-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-9-(4-vinylbenzyl)-9H-carbazole), alternating polymer formation, characterization, and capacitance measurements(Springer, 2013) Ateş, Murat; Uludağ, Nesimi; Karazehir, Tolga; Arican, FatihIn this work, (3,6-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-9-(4-vinylbenzyl)-9H-carbazole) (EDOTVBCz) comonomer was chemically synthesized and characterized by Fourier transform infrared (FTIR), proton nuclear magnetic resonance, and carbon nuclear magnetic resonance spectroscopy. EDOTVBCz was electrocoated on glassy carbon electrode (GCE) in various initial molar concentrations ([EDOTVBCz](0) = 1.0, 1.5, 2.0, and 3.0) in 0.1 M lithium perchlorate (LiClO4)/acetonitrile (CH3CN). P(EDOTVBCz)/GCE was characterized by cyclic voltammetry, FTIR reflectance-attenuated total reflection spectroscopy, scanning electron microscopy-energy dispersive X-ray analysis, atomic force microscopy, and electrochemical impedance spectroscopy (EIS). EIS was used to determine the capacitive behaviors of modified GCE via Nyquist, Bode magnitude, Bode phase, and admittance plots. The highest low-frequency capacitance value was obtained as C (LF) = similar to 2.35 mF cm(-2) for [EDOTVBCz](0) = 3.0 mM. Double-layer capacitance of the polymer/electrolyte system was calculated as C (dl) = similar to 2.78 mF cm(-2) for [EDOTVBCz](0) = 1.0 and 3.0 mM. The maximum phase angle was obtained as theta = similar to 76.7(o) for [EDOTVBCz](0) = 1.0, 1.5, 2.0, and 3.0 mM at the frequency of 20.6 Hz. AC impedance spectra of P(EDOTVBCz)/LiClO4/CH3CN was obtained by performing electrical equivalent circuit model of R(Q(R(CR))) with linear Kramers-Kronig test.Öğe A novel synthesis of 3,6-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-9-tosyl-9H-carbazole(Ovidius Univ Press, 2012) Ateş, Murat; Uludağ, Nesimi; Karazehir, Tolga; Arican, Fatih3,6-bis(2,3-dihydrothieno [3,4-b][1,4]dioxin-5-yl)-9-tosyl-9H-carbazole (EDOTTsCz) was synthesized and electrochemically polymerized on glassy carbon electrode (GCE) in 0.1 M tetrabutyl ammonium tetrafluoroborate (NB4BF4)/acetonitrile (CH3CN). Alternating copolymer was formed by CV method. Modified polymer electrode was characterized by Fourier transform Infrared Spectroscopy-Attenuated Transmission Reflectance (FTIR-ATR), Cyclic voltammetry (CV), Scanning electron microscopy-Energy dispersive X-ray analysis (SEM-EDX), Atomic force microscope (AFM) and Electrochemical impedance spectroscopy (EIS). Capacitive behaviors of the modified GCE were defined via Nyquist, Bode-magnitude, Bode-phase and Capacitance plots. A modified copolymer electrode provides enhanced capacitance evaluation, which may results in performance in energy storage devices.Öğe A novel synthesis of 4-toluene 9H-carbazole-9-carbodithioate, electropolymerization and impedance study(Budapest Univ Technol & Econ, 2014) Ateş, Murat; Uludağ, Nesimi; Karazehir, Tolga; Arican, FatihA novel synthesis of 4-toluene 9H-carbazole-9-carbodithioate (TCzC) was chemically synthesized and characterized by Fourier Transform Infrared (FTIR), proton nuclear magnetic resonance (H-1-NMR), and carbon nuclear magnetic resonance (C-13-NMR) spectroscopies. Specific (C-sp) and double layer capacitances (C-dl) of the electro-coated poly(carbazole) and poly(TCzC) films were obtained on glassy carbon electrode (GCE) by impedimetric method with DC potential from -0.1 to + 1.0 V by increasing potential of 0.2 V. The polymers were characterized by Cyclic voltammetry (CV), Fourier transform infrared reflectance-attenuated total reflection spectroscopy (FTIR-ATR), Atomic force microscopy (AFM), and Electrochemical impedance spectroscopy (EIS). The use of additional variable (DC potential) helped to disambiguate the equivalent circuit model of R(C(R(Q(RW))))(CR). Simulation results were compared with experimental data. In this study, substituted group effects of CS2 and tosyl on carbazole polymer were investigated by EIS technique. CS2 group together with tosyl group in the structure of carbazole decreased the specific capacitance value (C-sp = 0.43 mF cm(-2)) compared to PCz (C-sp = 1.44 mF cm(-2)). Electropolymerization formation was seriously affected by substituted groups of CS2 and tosyl on conjugation system because of the electron donor and acceptor ability.Öğe A novel synthesis of octahydropyrido[3,2-c]carbazole framework of aspidospermidine alkaloids and a combined computational, FT-IR, NMR, NBO, NLO, FMO, MEP study of the cis-4a-Ethyl-1(2hydroxyethyl)-2,3,4,4a,5,6,7,11c-octahydro-1H-pyrido[3,2-c] carbazole(Elsevier, 2018) Uludağ, Nesimi; Serdaroğlu, Goncagül; Yinanç, AbdullahIn this study, we performed a novel synthesis of the octahydropyrido[3,2-c]carbazole derivative 6 from 1 in five steps with a 34% overall yield. We also developed a unique compound 2 by a cyclization reaction from the cyanoethylation of compound 1, which is an intermediate step in the synthesis of Aspidospermidine. The parent compound of Aspidospermidine alkaloids, comprise a large family of diverse structures. As a result, we obtained octahydropyrido[3,2-c]carbazole (6)and the proposed method may be applicable to other alkaloids. All quantum chemical calculations of the cis-4a-Ethyl-1-(2-hydroxyethyl)-2,3,4,4a,5,6,7,11c-octahydro-1H-pyrido[3,2-c]carbazole have been performed with the DFT/B3LYP and HF methods by using the Gaussian 09W software package. The most stable conformer obtained from the Potential Energy Surface (PES) scan analysis at the B3LYP/6-31G** level of theory in the gas phase was used as the starting structure of the title compound to further computational analysis. The Natural Bond Orbital (NBO) and NLO analyses were performed to evaluate the intra-molecular interactions contributing to the molecular stability and to predict the optical properties of the title compound, respectively. Gauge-Independent Atomic Orbital (GIAO) approach was used to determine the H-1 and C-1 NMR chemical shifts of the title compound by subtracting the shielding constants of TMS at both methods. The calculated vibrational frequencies of the title compound were assigned by using the VEDA program and were scaled down by using the scaling factor 0.9668 for B3LYP/6-311++G(d, p) and 0.9050 for HF/6-311++G(d, p) to improve the calculated vibrational frequencies. The FMO (frontier molecular orbital) analysis was evaluated to predict the chemical and physical properties of the title compound and the HOMO, LUMO, and MEP diagrams were visualized by GaussView 4.1 program to present the reactive site of the title compound. (C) 2018 Elsevier B.V. All rights reserved.Öğe A SIMPLE AND EFFICIENT METHOD FOR CONSTRUCTING AZOCINO[4,3-b]INDOLE(Macedonian Journal of Chemistry and Chemical Engineering, 2022) Uludağ, NesimiA new synthetic procedure has been developed to prepare the biologically important azocino[4,3-b]indole via the tetrafluoro-1,4-benzoquinone (TFB)-mediated cyclization of a tetrahydrocarbazole derivative bearing an amide side chain at the C-2 position. For the first time, this strategy is based on a different method for the C-2 position of the tetrahydrocarbazole for the synthesis of methanoazocino[4,3-b]indole. The notable features of this protocol include its operational simplicity and high reaction yields. Furthermore, the structures of all the presently synthesized compounds were confirmed using spectroscopic methods (1H NMR, 13C NMR, FT-IR). © 2022,Macedonian Journal of Chemistry and Chemical Engineering.All Rights Reserved.Öğe An Effective Approach to the Strychnos Alkaloids: Total Synthesis of Tubifolidine(Springer, 2021) Uludağ, NesimiA facile total synthesis of tubifolidine has been developed, which is accomplished in an 11-step synthesis of the ABCDE pentacyclic of the strychnos alkaloids with an overall yield of 10%. The key steps are the cyclization reaction for starting tetrahydrocarbazoles bearing a nitrilealkyl side chain at the C-2 position, mediated by tetrachloro-1,4-benzoquinone (TCB) and the intramolecular addition of the amide as the nucleophile. This cyclization reaction was obtained with the relevant architecture, including strychnos skeletal-type alkaloids.Öğe An efficient method for the azocino[4,3-b]indole framework of strychnos alkaloids: OFT investigations on the electronic and spectroscopic properties(Scientific Publ-India, 2019) Uludağ, Nesimi; Serdaroğlu, Goncagül; Çolak, NakiTetracyclic 1,5-methanoazocino[4,3-b]indole (2) was achieved via a new synthetic approach for the synthesis of related strychnos alkaloids. These products embody the ABCD-ring system associated with the title alkaloids, as well as a one-pot construction of the ABCD ring system using tetrachloro-1,4-benzoquinone and tetrafluoro-1,4-benzoquinone, were involved as key steps. Also, the DFT-based quantum chemical calculations have been performed to evaluate the structural, electronic, and spectroscopic properties of the compound. PES (potential energy surface) scan revealed three stable conformers of the compound. The calculated FT-IR and NMR spectral data were compared with the corresponding observed values for the most stable conformer of the compound. Frontier Molecular Orbital analysis has revealed the chemical reactivity tendency and sites of the compound.Öğe An efficient studies on C-2 cyanomethylation of the indole synthesis: the electronic and spectroscopic characterization (FT-IR, NMR, UV-Vis), antioxidant activity, and theoretical calculations(Elsevier, 2022) Uludağ, Nesimi; Serdaroğlu, GoncagülThe direct cynamethylation with the development of catalyzed methodologies directed to 2-(cyanomethyl)indoles was reported by using tetrafluoro-1,4-benzoquinone (TFB) as the catalyst and it was synthesized in one step without protecting the indole N-H. Due to the plenty of synthesis indole moieties is currently the object of extensive investigations due to their biologically interesting role as the recognized block in many natural products and bioactive products. Moreover, the desired products were achieved in good yields. The antioxidant activity of the intermediates and the final product was explored by the DPPH method, and the results disclosed that the intermediate R2a and the final product could be used as promising agents in biomedicinal research. The structural and physicochemical properties of the intermediate and product indoles were enlightened by DFT calculations at B3LYP/6-311G(d,p) level, in the gas, CHCl3, methanol, and water environments. The TD-DFT calculations at the same level of theory were performed to compare with the recorded spectra of the studied compounds and to illuminate the possible electronic transitions (s(0) > s(n)) underlying the observed peaks. The NBO analyses of the compounds indicated that the n -> pi* and pi -> pi* interactions were a great portion of the lowering of the stabilization energy. The FMO analyses displayed that the intermediates and product, but the intermediate R2a mostly in all solvents, tended the electrodonating capability to the external molecular system. (C) 2021 Elsevier B.V. All rights reserved.Öğe An Efficient Synthesis of Nitriles from Aldoximes in the Presence of Trifluoromethanesulfonic Anhydride in Mild Conditions(Maik Nauka/Interperiodica/Springer, 2020) Uludağ, NesimiA new and convenient protocol has been proposed for the transformation of aldoximes to nitriles using trifluoromethanesulfonic anhydride and triethylamine. The proposed method allows a range of aldoximes, including aromatic, heterocyclic, aliphatic, and cycloaliphatic aldoximes, to be converted to the corresponding nitriles in good to excellent yields.
