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Bayrakçeken F Unlügedik A Hayvali M Yaman A 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(9):2109-2114
o-Xylene sensitized biacetyl fluorescence and phosphorescence have been investigated and photosensitized fluorescence and phosphorescence lifetimes of biacetyl in the vapor phase have been determined. Attempts to detect the triplet of biacetyl by its absorption spectrum were unsuccessful, primarily due to, it is believed, the low extinction coefficients of the triplet, and the low triplet concentrations produced by the optical pumping device at room temperature. 相似文献
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Zeliha Hayvalı Pınar Köksal 《Journal of inclusion phenomena and macrocyclic chemistry》2013,76(3-4):369-378
A series of new benzo-15-crown-5 derivatives (1–6) containing formyl and imine groups were prepared. New formyl crown ethers (1 and 2) were prepared by reaction of 4′,5′-bis(bromomethyl)benzo-15-crown-5 with 2-hydroxy-3-methoxybenzaldehyde (o-vanillin) and 2-hydroxy-5-methoxybenzaldehyde in the presence of NaOH. New Schiff bases (3–6) were synthesized by the condensation of corresponding aldehydes with 1,3-diaminopropane and 1,4-diaminobutane. Sodium and potassium complexes (1a–6a and 1b–6b) of the crown compounds forming crystalline complexes of 1:1 (Na+:ligand) and 1:2 (K+:ligand) stoichiometries were also synthesized. The structures of the aldehydes 1 and 2, imines 3–6 and complexes (1a–3a and 1b–3b) were confirmed on the basis of elemental analyses, IR, 1H- and 13C-NMR, and mass spectroscopy. 相似文献
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Novel amino- and thio(substituted)-1,4-naphthoquinone (NQ) compounds: Synthesis and characterization
Zeliha Gokmen Heba Alahmad 《Phosphorus, sulfur, and silicon and the related elements》2020,195(9):718-725
AbstractSynthesis of new 1,4-naphthoquinone derivatives is important in terms of searching new biologically active substances. In particular, compounds with piperazine and thiol moiety in their structure, show a wide range of pharmacological activity such as anti-inflammatory, anticancer, anti-fungal, anti-bacterial, anti-allergic, apoptosis and radical scavenging activities. In this study, new amino- and thio(substituted) naphthoquinone derivatives were synthesized by the reaction of thiols and thioalcohols with four naphthoquinone compounds which were used as starting materials. The new compounds were purified by column chromatography. The structure of the compounds was confirmed by different spectroscopic techniques. 相似文献
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Zeliha Hayvali Mustafa Hayvali Zeynel Kiliç Tuncer Hökelek Edwin Weber 《Journal of inclusion phenomena and macrocyclic chemistry》2003,45(3-4):285-294
Condensation reactions between 4'-formyl-5'-hydroxybenzo-15-crown-5and 2-aminopyridine, 2-amino-6-methylpyridine, 2-amino-4-methylpyridine or2-(aminomethyl)furan yielded the new laterally functionalized crown ethers1–4. The crown compounds 1–3 form crystalline 1:1 (Na+:ligand) complexes 1a–3a with sodium perchlorate. Ligands and complexes have been characterized by elemental analyses, IR, UV-Vis, 1H-, 13C-NMR and mass spectra. The tautomeric equilibria (phenol-imine, O...H–N and keto-amine, O...H–N forms) have been systematically studied by using UV-Vis absorption spectra. The spectra of the ligands 1–4 and complexes 1a–3a were recorded in polar, non-polar, acidic, and basic media. In solutions of polar solvents, tautomeric interconversion of the Schiff base into the keto-amine form has been observed. A crystal structure [monoclinic, space group P21/c,a = 14.292(2), b = 9.449(6), c = 16.059(2) Å, = 114.20(1)°,V = 1978.4(13) Å3, Z = 4 and Dx = 1.314 g cm-3] shows that compound 4 is in the form of phenol-imine in solid state. There is a strong intramolecular [O–H...N 1.78(6), O...N 2.581(7), O–H 0.89(6) Å and N...H–O 148.4(5)°] hydrogen bond between the phenolic oxygen and imine nitrogen atoms. The C=N imine bond reveals a trans planar (1E) configuration. The molecules stack in columns parallel to the a/c plane of the unit cell. 相似文献
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Mustafa Soylak Zeliha Erbas 《International journal of environmental analytical chemistry》2018,98(9):799-810
A novel vortex-assisted magnetic solid phase extraction method followed by flame atomic absorption spectrometry was improved to separate, preconcentrate and determine the lead, copper and cadmium ions by using 1-Nitro-2-naphthol-3, 6-disulfonic acid disodium salt (Nitroso-R salt) impregnated magnetic Ambersorb-563 resin. The adsorbent was characterised by Fourier transform infrared spectra, BET surface analyser and scanning electron microscopy. The influences of various analytical parameters, such as pH value, type and volume of the eluent, sample volume, were optimised and the effects of potentially interfering ions were investigated. The analyte ions were quantitatively recovered at pH 7.0 on magnetic adsorbent and desorbed with a 2.0 M HNO3 in 10% acetone as eluent. The detection limits were 1.4, 5.8 and 1.5 ng mL?1 for Cd(II), Cu(II) and Pb(II), respectively. The method has been validated with analytically by the analysis certified reference materials and standard additions prior to application to determine metal ions in water samples. 相似文献
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Tuncer Hökelek Necla Gündüz Zeliha Hayvali Zeynel Kiliç 《Journal of chemical crystallography》1995,25(12):831-836
The Schiff base ligand (1), [C15H17NO] crystallizes in the monoclinic space group P21/c witha=10.054(3),b=10.313(3), c=13.173(4)Å, =107.42(4)°,V=1303.2(7)Å3,Z=4,Dx=1.159 g cm–3, and (MoK)=0.674 cm–1. The C2-O[1.23(1)Å] and C3–C4 [1.33(2)Å] bond lengths are short, due to its quinoidal structure. In the Schiff base nickel complex (2), [Ni(C16H18NO)2] the asymmetric unit is comprised of two half-complexes. It crystallizes in the triclinic space group
witha=5.124(3),b=16.227(3),c=16.886(4)Å, =95.47(8), =96.00(1), =90.71(4)°,V=1389.6(9) Å3,Z=2,Dx=1.289 g cm–3, and (MoK) =12.1 cm–1. The coordination of the Ni(II) ions are square planar with bond angles between 87.9(1) and 92.1(1)°. The Ni–O and Ni–N distances are 1.819(2), 1.922(2) and 1.823(2), 1.914(3)Å in these two complexes. 相似文献
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A novel fluoroionophore compound was synthesized from a boron dipyrromethene (BODIPY) fluorophore and 4′-formylbenzo-15-crown-5 ionophore groups. Photophysical properties of the BODIPY-crown compound were studied with UV–Vis and fluorescence spectroscopy. The effect of metalic cations (Li+, Na+, K+, Mg2+, Ca2+, Ba2+, Al3+, Fe3+, Cu2+, Co2+, Zn2+, Ag+, Hg2+, Pb2+) on the absorption and fluorescence spectra of compound 2 was investigated. Blue shifts were detected in UV–Vis spectra upon addition of some metal ions (Al3+ > Fe3+ > Na+). At the same time, the emission intensity of this complex increased due to binding of Na+ ion to the benzo crown cavity. Additionally, a decrease in the intensity of the 630 nm emission peak and an increase in the intensity of the 570 nm emission peak was observed in the fluorescence emission spectra following addition of Al3+ and Fe3+ ions. 相似文献