Yazar "Demircan, Aydin" seçeneğine göre listele
Listeleniyor 1 - 20 / 20
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe 2-(4-Methoxy-2-methylanilino)-1,2-diphenylethanone(WILEY-BLACKWELL, 2011) Arslan, Hakan; Algul, Oztekin; Zirek, Selin; Tari, Ozden; Demircan, Aydin; Hardcastle, Kenneth I.The title compound, C22H21NO2, was synthesized from 4-methoxy-2-methylaniline and 2-hydroxy-1,2-diphenylethanone. In the title compound, the C-C-C-N-C backbone adopts an all-trans conformation. The crystal structure is stabilized by weak intermolecular C-H...O hydrogen-bond interactions.Öğe 3a-bromoperhydro-2,6a-epoxyoxireno[e][2]benzofuran(BLACKWELL PUBLISHING, 2007) Kosar, Basak; Karaarslan, Muhsin; Demircan, Aydin; Bueyuekguengoer, OrhanIn the title compound, C8H9BrO3, the boat form of the six-membered ring is almost symmetrical with respect to the epoxy bridge. The two five-membered rings generated by the epoxy bridge of the six-membered ring adopt envelope conformations, whereas the third five-membered ring adopts a half-chair conformation. The refinement results suggest partial inversion twinning.Öğe (3aR,4S,7R,7aS)-2-Phenyl-4-propyl-3a,4,7,7a-tetrahydro-1H-4,7-epithioisoindole-1,3-dione 8-oxide(WILEY-BLACKWELL, 2011) Demircan, Aydin; Sahin, Ertan; Beyazova, Gozde; Karaaslan, Muhsin; Hokelek, TuncerIn the tetrahydroisoindole moiety of the title compound, C17H17NO3S, the six-membered ring assumes a boat configuration and the -S=O group bridges the prow and stern of the boat. The phenyl ring is oriented at a dihedral angle of 83.2 (1)degrees with respect to the pyrrole ring. In the crystal, intermolecular C-H center dot center dot center dot O hydrogen bonds link the molecules into a three-dimensional network. A weak C-H center dot center dot center dot pi interaction involving the phenyl ring is also found. The crystal studied was an inversion twin.Öğe (3aR,6S,7aR)-7a-Bromo-2-[(4-methylphenyl)sulfonyl]-1,2,3,6,7,7a-hexahydro-3a,6-epoxyisoindole(WILEY-BLACKWELL, 2011) Kosar, Basak; Demircan, Aydin; Arslan, Hakan; Buyukgungor, OrhanIn the title compound, C15H16BrNO3S, the boat form of the six-membered ring is almost symmetrical with respect to the epoxy bridge. The two five-membered rings generated by the epoxy bridge of the six-membered ring adopt envelope conformations, whereas the N-containing five-membered ring adopts a twisted conformation. In the crystal, molecules are linked by C-H...O hydrogen bonds.Öğe (3aR,6S,7aR)-7a-Bromo-2-methylsulfonyl-1,2,3,6,7,7a-hexahydro-3a,6-epoxyisoindole(WILEY-BLACKWELL, 2011) Temel, Ersin; Demircan, Aydin; Arslan, Hakan; Buyukgungor, OrhanIn the title compound, C9H12BrNO3S, the two tetrahydrofuran rings adopt envelope conformations, the pyrrolidine ring adopts a half-chair conformation and the six-membered ring is in a boat conformation. In the crystal, weak intermolecular C-H...O hydrogen bonds link the molecules into R 2 (2)(8) and R 2 (2)(14) rings along the b-axis direction.Öğe 5-bromo-10-oxa-3-thiatricyclo[5.2.1.0(1,5)]-dec-8-ene 3,3-dioxide(BLACKWELL PUBLISHING, 2006) Kosar, Basak; Gokturk, Ersen; Demircan, Aydin; Buyukgungor, OrhanIn the title compound, C8H9BrO3S, the six-membered ring has a boat conformation, the two O-containing five-membered rings have envelope conformations and the tetrahydrothiophene ring has a twist conformation. The molecules are linked only by weak van der Waals interactions.Öğe 5-chloro-10-oxa-3-thiatricyclo[5.2.1.0(1,5)] dec-8-ene 3,3-dioxide(BLACKWELL PUBLISHING, 2006) Kosar, Basak; Gokturk, Ersen; Demircan, Aydin; Buyukgungor, OrhanThe title compound, C8H9ClO3S, has been synthesized from 2( 2-chloroallylsulfanylmethyl) furan by intramolecular thermal cycloaddition. The boat form of the six-membered ring is almost symmetric with respect to the epoxy bridge, and the five-membered ring containing the S atom has an envelope conformation.Öğe A facile synthesis of heterotricycles from furfurylbromoalkenes using thermal imda cycloaddition(2006) Demircan, Aydin; Karaarslan, Muhsin; Turaç, ErsenA variety of key precursors to the IMDA reaction of furan diene have been prepared via fa alkylation. Subsequently, rigid tricyclic compounds (2a-g) possessing oxygen, nitrogen, and sulfur been synthesized by employing thermal intramolecular Diels-Alder reactions. These heterocyclic fu tricycles include a bromo quaternary carbon centre obtained stereoselectively with moderate yields (32 % overall). © 2011 by Walter de Gruyter GmbH & Co. All rights reserved.Öğe A Study of Palladium Catalyzed Intra/Intermolecular Cascade Cross Coupling/Cyclizations Involving Bicyclopropylidene(MDPI AG, 2014) Demircan, AydinThe compounds [3-(2-Bromocyclohex-2-enyloxy) prop-1-ynyl]-tert-butyldimethylsilane 3, [4-(2-bromocyclohex-2-en-1-yloxy)but-2-yn-1-yloxy] tert-butyldimethylsilane 5 and dimethyl 2-(2-bromocyclohex-2-enyl)-2-(3-(tert-butyldimethylsilanyl) prop-2ynyl) malonate 9 were prepared and subjected to palladium-catalyzed intra-intermolecular cascade cross couplings incorporating bicyclopropylidene 10 under two types of conditions. In the presence of Pd(OAc)(2), PPh3 and K2CO3 in acetonitrile at 80 degrees C, the products were indene analogues, cross-conjugated tetraenes 11, 12 and 13, respectively. The corresponding spirocyclopropanated tricycle 16 in dimethylformamide at 110 degrees C was obtained, albeit in low yield (24%), and observed as an equimolar mixture of diastereomers, whereas 14, 15 were not fully isolated.Öğe Ab initio studies on 5-bromo-10-oxa-3-Thiatricyclo[5.2.1.01,5]-dec-8-ene 3,3-dioxide(SLOVENSKO KEMIJSKO DRUSTVO, 2007) Arslan, Hakan; Demircan, Aydin5-Bromo-10-oxa-3-thiatricyclo[5.2.1.0(1,5)]-dec-8-ene3,3-dioxide (BOTCDO) was synthesized from the reaction between 2-(2-bromoallylsulfanylmethyl)-furan and m-chloroperbenzoic acid in dichloromethane. The molecular structure and vibrational frequencies of BOTCDO in the ground state have been investigated with ab initio (HF) and density functional theory methods (B3LYP, B3PW91 and MPW1PW91) implementing the standard 6-31G(d) basis set. The optimized geometric bond lengths and bond angles obtained by using HF and DFT methods show the best agreement with the experimental data. Comparison of the observed fundamental vibrational frequencies of title compound and calculated results by HF and DFT methods indicate that MPW1PW91 is superior to the scaled HF approach for molecular problems. Optimal uniform scaling factors calculated for the title compound are 0.8920, 0.9553, 0.9518 and 0.9452 for HF, B3LYP, B3PW91 and MPW1PW91 methods, respectively.Öğe Crystal structure, Hirshfeld surfaces and DFT computation of (E)-(5-methylfuran-2-yl) (morpholino) methanone oxime(Int Union Crystallography, 2016) Temel, Ersin; Demircan, Aydin; Colak, Medine[Abstract Not Available]Öğe Crystal structure, spectroscopic investigations and quantum chemical calculation studies of (3aR,6S,7aR)-7a-bromo-6-methyl-2-[(4-methylphenyl)sulfonyl]-1,2,3,6,7,7a-hexahydro-3a,6-epoxyisoindole: A combined experimental and theoretical studies(ELSEVIER SCIENCE BV, 2016) Alasalvar, Can; Demircan, Aydin; Kosar, Basak; Pekacar, Ali Ihsan; Buyukgungor, OrhanThe crystal structure and spectroscopic properties of (3aR,65,7aR)-7a-bromo-6-methyl-2-[(4-methylphenyl)sulfonyl]-1,2,3,6,7,7a-hexahydro-3a,6-epoxyisoindole were determined by X-ray diffraction, IR and (CNMR)-C-13 and H-1 NMR spectroscopytechniques. We investigate molecular and crystal structure of the new sulfonamide, which was derived from an environmental friendly cyclization reaction in water. This work allow to the development of a stereo-selective tandem allylamine isomerization/Diels Alder cyclo-addition sequence led to rapid assembly of complex nitrogen containing heterocycles. The molecular geometry from X-ray determination, vibrational frequencies and NMR shifts values of the title compound in the ground state have been calculated by using CAM-B3LYP and B3LYP methods with 6-311++G(d,p) basis sets. The calculated results show that the optimized geometry can well regenerate the crystal structure and theoretical vibrational frequencies and chemical shift data are in good agreement with experimental data. Besides, it is examined nonlinear optic properties, molecular electrostatic potential map and HOMO-LUMO orbitals of the molecule. (C) 2016 Elsevier B.V. All rights reserved.Öğe One-Pot Cascade Synthesis of Fused Nitrogen-Containing Heterocycles in Aqueous Media - Utility of N-Protective Groups in Intramolecular Diels-Alder Reaction of Furan(GEORG THIEME VERLAG KG, 2016) Demircan, Aydin; Kandemir, Muhammet K.; Colak, Medine; Karaarslan, MuhsinA metal-free, thermal, intramolecular Diels-Alder (IMDA) reaction of furan in aqueous media without the use of microwave irradiation was investigated. Protection of the amine functionality and the cycloaddition reaction were performed as a one-pot, two-component process. Various nitrogen-protecting groups and their electronic and steric effects on the cycloaddition reaction were studied. The protection-intramolecular Diels-Alder reaction sequence proceeds under environmentally benign aqueous conditions, which are tolerated by substrates with a broad range of nitrogen-protecting groups such as benzyloxycarbonyl (Cbz), trityl, tert-butoxycarbonyl (Boc), trifluoroacetyl, tosyl, mesyl, and p-nosyl [(4-nitrophenyl)sulfonyl]. This study allowed the development of a stereoselective, tandem allylamine isomerization-Diels-Alder cycloaddition sequence leading to the rapid assembly of complex nitrogen-containing heterocycles in a simple one-pot process.Öğe Preparation of heterotricyclic chlorides via intramolecular Diels-Alder reaction of furans(ASIAN JOURNAL OF CHEMISTRY, 2007) Karaarslan, Muhsin; Demircan, AydinA variety of key precursors to the intramolecular Diels-Alder (IMDA) reaction of furan diene have been prepared via facile alkylation. Subsequently, rigid heterotricyclic chlorides 5a-e possessing oxygen, nitrogen and sulfur have been synthesized by employing a thermal IMDA reactions. Use of bulky protecting group on nitrogen 5a-b, such as t-butoxy group, can be utilized to encourage cycloaddition reactions that otherwise does not proceed.Öğe Push-Pull Triazenes Derived from 1-(Benzylideneamino)- and 1-(Sulfonimido)-azolylidenes(AMER CHEMICAL SOC, 2013) Jishkariani, Davit; Hall, C. Dennis; Demircan, Aydin; Tomlin, Blake J.; Steel, Peter J.; Katritzky, Alan R.In-situ-generated neutral 1-(benzylideneamino)- and novel anionic 1-(sulfonimido)-azolylidenes react with organic azides to afford diverse classes of push-pull triazenes and triazene salts. The scope of the heterocyclic core and substituents at the N1 and N3 positions of NHC precursors together with the thermal properties of resulting compounds were examined.Öğe Structure and vibrational spectra of tert-butyl N-(2-bromcicyclohex-2-enyl)-N-(2-furylmethyl)carbamate(Peking Univ Press, 2007) Arslan, Hakan; Demircan, AydinThe molecular structure, conformational stability, and vibrational frequencies of tert-butyl N-(2-bromocyclohex-2-enyl)-N-(2-furylmethyl)carbamate (TBBFC) were investigated by utilizing the Hartree-Fock(HF) and density functional theory (DFT) ab initio calculations with 6-31G* and 6-31G * * basis sets. The optimized bond length and angle values obtained by HF method showed the best agreement with the experimental values. Comparison of the observed and calculated fundamental vibrational frequencies indicated that B3LYP was superior to the scaled HF approach for molecular problems. Optimal uniform scaling factors calculated for the title compound are 0.899/0.904, 0.958/0.961, and 0.988/0.989 for HF, B3LYP, and BLYP (6-31G */6-.31G* *), respectively.Öğe Subtractive-FTIR spectroscopy to characterize organic matter in lignite samples from different depths(PERGAMON-ELSEVIER SCIENCE LTD, 2012) Gezici, Orhan; Demir, Ibrahim; Demircan, Aydin; Unlu, Nuri; Karaarslan, MuhsinOrganic matter present in lignite samples collected from different depths (i.e. top, mid and bottom) of lignite source. Ilgin, Konya province, was examined by using subtractive-FTIR-ATR spectroscopy. FTIR spectra were recorded on (i) original samples, (ii) the samples dried at 105 degrees C and (iii) the samples acid-treated and dried. After a combustion process performed for each sample at 650 degrees C for 15 min, the spectra of samples were recorded and subtracted from the spectra of untreated samples. Hence, a software-based subtraction made it possible to acquire a representative spectra related with organic matter. As the contribution of the bands related with inorganic constituents in lignite samples were eliminated after spectrum-subtraction procedure, difference-spectra led analyzing the spectra related with organic matter in lignite samples, reasonably. Furthermore, the bands related with acidic functional groups, aromatic and aliphatic structures were analyzed on the basis of difference-spectra, easily. From the difference-spectra it was shown that an acid-treatment process under mild conditions caused shift in some specific bands related with carbonyl groups of carboxyls so that the band at around 1710 cm(-1) arisen, while the intensity of the band at around 1420 cm(-1) was diminished. Through the acid-treatment process, acidic groups in lignite samples from different depths were thought to be turned into similar forms by protonation and/or stripping of metal ions originally bonded. Difference-spectra acquired for acid-treated samples made it possible to evaluate the form of carboxylic acid groups present in the studied samples under specific environmental conditions. Hence, a facile and environmentally-friendly methodology was used to analyze organic matter in lignite by using FTIR spectra, and valuable information was acquired about the aliphatic, aromatic and acidic character of the studied lignite samples collected from different depths. The proposed methodology seems to be promising in acquiring approximate representative spectra for lignite organic matter by using little or no chemicals. (C) 2012 Elsevier B.V. All rights reserved.Öğe Synthesis and characterization of conducting copolymer of Trans-1-(4-methyl-3'-thienyl)-2-(ferrocenyl)ethene with EDOT(WILEY-BLACKWELL, 2012) Turac, Ersen; Sahmetlioglu, Ertugrul; Demircan, Aydin; Toppare, LeventFerrocene-substituted conducting polymer namely poly(trans-1-(4-methyl-3'-thienyl)-2-(ferrocenyl)ethene-co-3,4-ethylenedioxythiophene) [P(MTFE-co-EDOT)] was synthesized and its electrochromic properties were studied. Monomer, MTFE, was obtained using 2-(ferrocenyl)ethene and 3-methyl-4-bromothiophene. The structure of monomer was determined via Fourier transform infrared spectroscopy (FTIR), 1H-NMR, and 13C-NMR techniques. The copolymer was synthesized using this monomer and EDOT. The resulting copolymer P(MTFE-co-EDOT) was characterized by cyclic voltammetry, FTIR, scanning electron microscopy, atomic force microscopy, and UVvis spectroscopy. The conductivity measurements of copolymer and PEDOT were accomplished by the four-probe technique. Although poly(trans-1-(4-methyl-3'-thienyl)-2-(ferrocenyl)ethene) [P(MTFE)] reveals no electrochromic activity, its copolymer with EDOT has two different colors (violet and gray). Band gap (Eg) and ?max of P(MTFE-co-EDOT) were determined. (c) 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012Öğe tert-Butyl 3a-chloro-2-methylperhydro-2,6a-epoxy-oxireno[e] isoindole-5-carboxylate(INT UNION CRYSTALLOGRAPHY, 2007) Kosar, Basak; Karaarslan, Muhsin; Yildiz, Yasar Kemal; Demircan, Aydin; Buyukgungor, OrhanIn the title compound, C14H2OClNO4, the molecules are linked only by weak van der Waals interactions, and the three five-membered rings adopt envelope conformations.Öğe Vibrational Spectroscopy Investigation Using Ab Initio and Density Functional Theory Analysis on the Structure of tert-Butyl 3a-Chloroperhydero-2,6a-epoxyoxireno[e]isoindole-5-carboxylate(HINDAWI LTD, 2013) Arslan, Hakan; Demircan, Aydin; Binzet, Gun; Ilhan, Ilhan OzerThe molecular structure, vibrational frequencies, and infrared intensities of the tert-butyl 3a-Chloroperhydero-2,6a-epoxyoxireno[e]isoindole-5-carboxylate were calculated by the HF and DFT (BLYP and B3LYP) methods using 6-31G(d) and 6-31G(d,p) basis sets. The FT infrared spectrum of the solid sample was measured under standard condition. We obtained two stable conformers for the title compound; however Conformer 1 is approximately 0.2kcal/mol more stable than the Conformer 2. The comparison of the theoretical and experimental geometry of title compound shows that the X-ray parameters fairly well reproduce the geometry of Conformer 2. Comparison of the fundamental vibrational frequencies of the title molecule and calculated results by HF and DFT methods indicates the B3LYP is superior for molecular vibrational problems. The harmonic vibrations computed by the B3LYP/6-31G(d,p) methods are in a good agreement with the observed IR spectral data. Theoretical vibrational spectra of the compound were interpreted by means of potential energy distributions (PEDs) using VEDA 4 program.
