Other
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Scientific MembershipsTurkish National Crystallographic Association
British Crystallographic Association
Publications (59) View all
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Article: Synthesis and structural characterization of Palladium(II) complex bearing N-Heterocyclic Carbene
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ABSTRACT: Trans-Bis[1,3-bis(2,4-dimethylphenylimidazolidin-2-ylidene)]dichloropalladium(II), 4, was prepared from 1,3-bis(2,4-dimetilphenyl)imidazoliniumchloride. The crystal and molecular structure of 4 have been determined by single crystal X-ray diffraction. The title compound, C38H44N4PdCl2, crystalizes in the monoclinic space group P 21/n with a=13.8713(9)Å, b=12.1365(6)Å, c=21.5499(15)Å. The Pd atom has a slightly distorted square planar coordination geometry. The molecules of the title compound are linked by C–H···Cl weak hydrogen bonds into two-dimensional sheets parallel to the (001) plane. In addition, the title compound was characterized by elemental analyses and NMR spectroscopy.Structural Chemistry 05/2012; 19(1):57-62. · 1.85 Impact Factor -
SourceAvailable from: Hasan Karabıyık
Article: Aromaticity balance, π-electron cooperativity and H-bonding properties in tautomerism of salicylideneaniline: the quantum theory of atoms in molecules (QTAIM) approach.
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ABSTRACT: Topological analysis based on DFT calculations regarding proton transfer reaction in salicylideneaniline (SA) was performed to scrutinize possible changes in the intramolecular H-bond, π-electron delocalization and aromaticity levels of certain fragments. Quantum chemical calculations and natural bond orbital (NBO) analyses were carried out over a tautomeric ensemble whose members correspond to the molecules at different stages in tautomeric interconversion of SA. The elaboration of intramolecular hydrogen bonding in terms of the relevant topological parameters and the interpretation of certain dependencies regarding its strength were examined. The results show that delocalization index (DI) between donor and acceptor atom δ(O,N) is a useful topological parameter for describing H-bond strength, which is influenced by π-delocalization level within quasiaromatic chelate ring, indicating its resonance-assisted character. NBO analyses reveal that lone-pair (LP) population on N center also affects the strength of intramolecular H-bond in SA. Furthermore, π-electron transfer accompanying intramolecular proton migration in SA is brought into being through formally vacant non-Lewis type LP* orbital on the tautomeric proton. As a result of this, tautomeric protons in molecular entities near TS have hypovalent character due to the lack of electron population in the bonding orbital relative to that in LP* orbital. While H-bonds in the tautomeric ensemble of SA are predominantly partial covalent, molecular entities close to transition state have the strongest covalent H-bonds. The most important result is also that there are linear correlations between the orders of bonds (hydroxyl and amine) involving intramolecular H-bond and electron density values at the relevant BCPs due to partially covalent character of these bonds, contrary to exponential behavior as for purely covalent bonds. Quasiaromatic chelate ring formation is established not only to compel a reduced aromaticity of salicylidene ring but also to decrease in LP-population on N.Journal of Molecular Modeling 06/2011; 17(6):1295-309. · 1.80 Impact Factor -
SourceAvailable from: Secil Celik
Article: 2,5-Dihexyl-3,6-diphenyl-pyrrolo-[3,4-c]pyrrole-1,4(2H,5H)-dione.
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ABSTRACT: The asymmetric unit of the title compound, C(30)H(36)N(2)O(2), contains one half-mol-ecule, the other half being generated by a crystallographic inversion centre. The crystal structure is devoid of any classical hydrogen bonds however, non-classical C-H⋯O inter-actions link the mol-ecules into chains propagating in [001] and a C-H⋯π inter-action leads to the formation of a two-dimensional network in (011).Acta Crystallographica Section E Structure Reports Online 01/2010; 66(Pt 7):o1546. · 0.35 Impact Factor -
SourceAvailable from: Muhittin Aygün
Article: 1,3-Di-3-pyridyl-2,3-dihydro-1H-naphth[1,2-e][1,3]oxazine.
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ABSTRACT: In the crystal structure of the title compound, C(22)H(17)N(3)O, the oxazine ring has a half-chair conformation. The dihedral angles between the best least-squares plane through the pyridine rings and the planar part (O-C-C-C-N) of the oxazine ring are 72.14 (6) and 35.44 (7)°, the smaller angle involving the pyridine ring adjacent to the oxazine O atom. The mol-ecule has two stereogenic centers at the oxazine carbons, RS and SR. The crystal packing reveals that symmetry-related mol-ecules are linked by inter-molecular N-H⋯N hydrogen bonds to form chains parallel to the b axis.Acta Crystallographica Section E Structure Reports Online 01/2008; 64(Pt 3):o573. · 0.35 Impact Factor -
Article: Rh(I) and Pd(II) complexes of methoxy functionalized heterocyclic carbene: Synthesis and characterization
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ABSTRACT: A new methoxy functionalized 2-(trichloromethyl)-1,3-diarylimidazolidin (6) was synthesized as the precursor for N-heterocyclic carbene complexes of Pd(II) and Rh(I) by the condensation of N,N'-bis(2,4-dimethoxyphenyl)-1,2-diaminoethane with chloral. The structures of all compounds have been elucidated by a combination of multinuclear NMR spectroscopy, elemental analysis and in one instance, by single crystal X-ray diffraction. Compound 8, C27H34N2O4ClRh, crystallizes in the triclinic space group P-1 with cell dimensions a = 9.7642(12)Å, b = 11.1914(11)Å, c = 13.0102(14)Å, α = 104.034(9)°, β = 106.658(9)°, γ = 99.658(9)° with Z = 2. The molecular structure of 8 shows the geometry around the Rh metal to be a slightly distorted square planar. The crystal structure shows the formation of centrosymmetric dimers via intermolecular C-H...Cl hydrogen bonds. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)Crystal Research and Technology 05/2006; 41(6):615 - 621. · 0.95 Impact Factor