The transfer of Pb 2 + facilitated by interfacial complexation with 5-(4-phenoxyphenyl)-6H-1,3, 4... more The transfer of Pb 2 + facilitated by interfacial complexation with 5-(4-phenoxyphenyl)-6H-1,3, 4-thiadiazin-2-amine (PPTA) at the polarized water/1,2-dicholoroethane (1,2-DCE) interface was investigated by cyclic voltammetry. We synthesized the thiadiazine derivative, PPTA, firstly. The transfer was performed at different metal concentrations and scan rates, and the obtained voltammetric transfer peaks toward Pb 2+ ion over other divalent cations (Zn 2+ , Co 2+ , Ni 2+ , Cd 2+ , Hg 2+ , and Cu 2+) were reversible. The dependence of the half-wave potentials of the Pb 2 + ion on the concentration of PPTA in the organic phase indicates that the ion transfer is facilitated by the formation of 1:2 (metal:ligand) complex in the organic phase with the association constant (lgβ2) of (17.1±0.2).
Fluorescent labeling of L-929 fibroblast cells was studied by using newly synthesized ligand whic... more Fluorescent labeling of L-929 fibroblast cells was studied by using newly synthesized ligand which was named as 2- N -methylamino-5-(pyrene-1-yl)-thiazole (ABS 40). The maximum fluorescence intensity of ABS 40 was detected at an excitation and emission wavelengths of 350 nm and 400 nm. Fluorescence intensity of the ligand was changed by the addition of DNA from calf thymus (CT-DNA) and human serum albumin (HSA). Both biomolecules and ABS 40 formed complexes that changed the fluorescence intensity of the ligand at the given wavelengths. Cytotoxicity tests were done with XTT analysis. L-929 fibroblast cells were cultured in the presence of ABS 40 to show cell labeling. Results showed that ABS 40 at 318 μM was labeled the cells at an excitation wavelength of 403.7 nm by using confocal microscopy. in vivo cell labeling was also confirmed by using Ct-DNA immobilized iron nanoparticles.
A novel calix[4]arene derivative containing benzothiazole azo groups at the upper rim was synthes... more A novel calix[4]arene derivative containing benzothiazole azo groups at the upper rim was synthesized as chromogenic chemosensor, and its binding and sensing properties with heavy metal ions (Pb(2+), Hg(2+), Ni(2+), Cd(2+), Cu(2+), Zn(2+), Co(2+), Fe(2+), Mn(2+), Cr(3+), Ag(+)) were investigated by UV-vis spectroscopy and voltammetric techniques. The results of spectroscopic and voltammetric experiments showed that the chromogenic chemosensor has high selectivity towards Hg(2+) ion over the other heavy metal ions. Moreover, it was shown that the interaction between Hg(2+) and the chromogenic chemosensor occurs by means of the benzothiazole azo groups at the upper rim by using differential pulse voltammetry. The stoichiometric ratio and the association constant were determined as 1:1 and (6.1+/-0.3)x10(5) L mol(-1) for the complex between Hg(2+) and the ionophore. Furthermore, we prepared a rapid test kit for early detection of Hg(2+) in aqueous environment in the concentration range of 1 x 10(-4) to 1 x 10(-2)M.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2014
h i g h l i g h t s New thiazole derivative have been synthesized and characterized. Complexation... more h i g h l i g h t s New thiazole derivative have been synthesized and characterized. Complexation behaviors for various anionic species investigated. It is a very good naked eye detection sensor for the fluoride anion.
Four new tripodal-benzimidazole derivatives were synthesized by Schiff base reaction between 2,4,... more Four new tripodal-benzimidazole derivatives were synthesized by Schiff base reaction between 2,4,6tris(p-formylphenoxy)-1,3,5-triazine (TRIPOD) and different diamine derivatives. The structures of the obtained compounds were identified by FT-IR, 1 H NMR, 13 C NMR and UV-vis spectral data, thermal analysis and elemental analysis. Electrochemical behaviors of the compounds were studied by cyclic voltammetry in DMF including 0.1 M [NBu 4 ] [PF 6 ]. The voltammograms showed peaks having similar characteristics except tripodal-benzimidazole including-NO 2 derivative. In addition, their antimicrobial activities were evaluated by using the standard disk diffusion method in dimethylformamide media. The activities were determined against 4 bacteria cultures by comparing to those of gentamycin.
The transfer of alkali and alkaline-earth metal ions facilitated by a calix[4]arene derivative, 2... more The transfer of alkali and alkaline-earth metal ions facilitated by a calix[4]arene derivative, 25,27-di [(2-ethoxy)benzaldehyde]-26,28-dihydroxy-5,11,17,23-tetra(tert-butyl) calix[4]arene (DBC4), across a water/1,2-dichloroethane (1,2-DCE) micro-interface supported at the tip of a micropipette was investigated. The well-defined voltammetric behavior was obtained only for Na + ion among the used metal ions by using the electrochemical methods. The measurements were performed when the bulk concentration of Na + ion in the aqueous phase is much higher than that of DBC4 in the organic phase, and vice versa. The diffusion coefficient of DBC4 in the DCE phase was calculated to be equal to (4.2 ± 0.2) Â 10 À6 cm 2 s À1. The logarithm of the association constant of DBC4-Na + complex having 1:1 stoichiometry in 1,2-DCE was determined as 3.99. The differential pulse voltammetry was used for amperometric detection of Na + ion in chloride medium. The results show that DBC4 can be used for many analytical applications such as ion recognition and fabrication of electrochemical sensor for Na + ion because of its good selectivity.
In this study, a novel azocalix[4]arene derivative, 5,11,17-tris[(1-naphtyl)azo]-25,26,27,28-tetr... more In this study, a novel azocalix[4]arene derivative, 5,11,17-tris[(1-naphtyl)azo]-25,26,27,28-tetrahydroxy -calix[4]arene (NAC4) bearing napthyl groups on the upper rim was synthesized. Its complexation behavior for alkali, alkaline-earth and various heavy metal ions (Li + , Na + , K + , Rb + , ...
Acetyldiphenyl ether and 4,4-diacetyldiphenyl ether were synthesized from diphenyl ether and acet... more Acetyldiphenyl ether and 4,4-diacetyldiphenyl ether were synthesized from diphenyl ether and acetyl chloride in the presence of AlCl3 used as catalyst. Subsequently, their keto oxime and glyoxime derivatives were prepared. The metal complexes of the glyoximes such as Cu(II), Ni(II) and Co(II) were also prepared. The structures of these ligands and their complexes were identified by FT-IR, 1 H NMR and 13 C NMR spectral data, elemental analysis and magnetic measurements.
In this study, some thiazole-based pyrrolidine derivatives were synthesized, characterized by FT-... more In this study, some thiazole-based pyrrolidine derivatives were synthesized, characterized by FT-IR and 1H NMR spectroscopic techniques, and evaluated as potential antibacterial agents. Their antibacterial activities were evaluated by broth microdilution method and expressed as minimum inhibitory concentration; against Escherichia coli, Salmonella typhimurium, Bacillus cereus, and Staphylococcus aureus. Cytotoxicity studies of synthesized compounds were also conducted to minimize the toxic effects on healthy mammalian cells. From synthesized compounds, 4-F-phenyl derivative compound (11) has been found to inhibit Gram-positive bacteria with minimum toxicity selectively.
4-(Chloroacetyl)diphenyl ether (I) was synthesized from chloroacetyl chloride and diphenyl ether ... more 4-(Chloroacetyl)diphenyl ether (I) was synthesized from chloroacetyl chloride and diphenyl ether in the presence of AlCl3 as catalyst in a Friedel-Crafts reaction. Subsequently, its keto oxime (II) derivative was prepared. Then 3 new substituted 4-(alkylaminoisonitrosoacetyl)diphenyl ether ligands derived from 4-(phenoxy)phenyloxylohydroxymoyl chloride and corresponding amines were synthesized. The following aromatic and aliphatic amines were used for the ligands ethanolamine, 2-amino-4-methylphenol, and
The oxidation of some cyanocycloheptatrienes with CrO3 and pyridine was investigated and a few ne... more The oxidation of some cyanocycloheptatrienes with CrO3 and pyridine was investigated and a few new nitrile functionalised benzotropone derivatives were obtained. Photooxygenation reaction of these products was also studied. The structures of the formed products were determined on the basis of NMR spectroscopy and the formation mechanism of unusual products was discussed. Human carbonic anhydrase isoenzymes I, and II (hCA I and hCA II) inhibition properties of nitrile functionalized new benzotropone derivatives were also studied. Both CA isozymes were inhibited in the low micromolar range by these nitrile functionalized benzotropone analogues. The newly synthesized benzotropone derivatives showed inhibition constants in the sub-micromolar range (2.51-4.06μM). The best hCA I inhibition was observed in 5H-benzocycloheptene-7-carbonitrile (Ki: 2.88±0.86μM). On the other hand, 5-oxo-5H-benzocycloheptatriene-7-carbonitrile showed the powerful inhibitory effect against hCA II (Ki: 2.51±0.34μM).
The ESR spectra analysis indicated the formation of two identical radicals on irradiated 4,4 0-bi... more The ESR spectra analysis indicated the formation of two identical radicals on irradiated 4,4 0-bis(chloroacetyl)diphenylether polycrystal. It was determined that the produced radical structures on 4,4 0-bis(chloroacetyl)diphenylether irradiated were stable.
Journal of Inclusion Phenomena and Macrocyclic Chemistry, 2007
A doubly fused porphyrin has been synthesized by two successive cyclization reactions. The first ... more A doubly fused porphyrin has been synthesized by two successive cyclization reactions. The first meso-phenyl group was fused by an intramolecular Cadogan reaction leading to an enamine-functionalized porphyrin. After Vilsmeier-Haack formylation of the nickel enaminoporphyrin, an intramolecular Friedel-Crafts reaction followed by dehydration of the intermediate alcohol afforded the doubly fused aromatic nickel porphyrin, which could be demetalated. The free base
Journal of Inclusion Phenomena and Macrocyclic Chemistry, 2007
4-(Chloroacetyl)diphenyl thioether (1) was synthesized from chloroacetyl chloride and diphenyl th... more 4-(Chloroacetyl)diphenyl thioether (1) was synthesized from chloroacetyl chloride and diphenyl thioether in the presence of AlCl 3 as catalyst in a Friedel-Crafts reaction. Subsequently, its keto oxime (2) and glyoxime (3) derivatives were prepared. N-(4 0-Benzo[15crown-5]thiophenoxyphenylaminoglyoxime (H 2 L) and its sodium chloride complex (H 2 L Á NaCl) were prepared from 4-(thiophenoxy)chlorophenylglyoxime (3), 4 0-aminobenzo[15-crown-5] and sodium bicarbonate or sodium bicarbonate and sodium chloride. Ni(II), Co(II) and Cu(II) complexes of H 2 L and H 2 L Á NaCl have a metal-ligand ratio of 1:2 and the ligand coordinates through the two N atoms, as do most of the vic-dioximes. The BF 2-capped Ni(II) mononuclear complex of the vic-dioxime was prepared. The macrocyclic ligands and their transition metal complexes were characterized on the basis of FT-IR, 1 H NMR, 13 C NMR spectroscopy and elemental analyses data.
2,4,6-tris(4-hydroxybenzimino)-1,3,5-triazine [1,2] (III) have been synthesized by the reaction o... more 2,4,6-tris(4-hydroxybenzimino)-1,3,5-triazine [1,2] (III) have been synthesized by the reaction of 1 equiv melamine and three equiv 4-hydroxybenzaldehyde, and characterized by means of elemental anal-ysis, 1H-NMR (nuclear magnetic resonance spectroscopy), Fourier ...
A new silica gel compound modified 4,4&am... more A new silica gel compound modified 4,4'-oxy-bis(chlorophenylglyoxime) (CPGO) was synthesized and characterized by infrared spectroscopy, elemental analysis and thermogravimetric analysis. The sorption capacity of such a matrix towards Co(II), Ni(II) and Cu(II) from aqueous solutions was studied. The optimum pH values for the separation of these divalent cations on the sorbent were 5.0, 6.0 and 6.0 for Cu, Co and Ni, respectively. The process of metal separation was followed by batch method, and fitted to a Langmuir and Freundlich sorption isotherms. The maximum sorption capacities (0.055, 0.042, and 0.034 mmol g(-1)) were found from the Langmuir equation and the enthalpies of binding were 44.96, 71.63, and 68.14 kJ mol(-1) for Cu, Co and Ni, respectively. The other thermodynamic parameters calculated from the adsorption results were used to explain the mechanism of the adsorption. For example, the Gibbs free energies of binding agree with the spontaneity of the proposed reaction between cations and basic centers.
4,4 -Bis(chloroacetyl)diphenyl thioether (HL) was synthesized from chloroacetyl chloride and diph... more 4,4 -Bis(chloroacetyl)diphenyl thioether (HL) was synthesized from chloroacetyl chloride and diphenyl thioether in the presence of AlCl3 as catalyst in a Friedel-Crafts reaction. Subsequently, its keto oxime (H2L) and glyoxime (H4L) derivatives were also prepared. ...
In addition to the synthetic aspects, the chemistry of endoperoxides has fascinated organic chemi... more In addition to the synthetic aspects, the chemistry of endoperoxides has fascinated organic chemists for long years. 7 As a direct consequence of this, we have been interested in the oxidation reactions of different tropone and tropolone derivatives in order to develop new synthetic strategies ...
The transfer of Pb 2 + facilitated by interfacial complexation with 5-(4-phenoxyphenyl)-6H-1,3, 4... more The transfer of Pb 2 + facilitated by interfacial complexation with 5-(4-phenoxyphenyl)-6H-1,3, 4-thiadiazin-2-amine (PPTA) at the polarized water/1,2-dicholoroethane (1,2-DCE) interface was investigated by cyclic voltammetry. We synthesized the thiadiazine derivative, PPTA, firstly. The transfer was performed at different metal concentrations and scan rates, and the obtained voltammetric transfer peaks toward Pb 2+ ion over other divalent cations (Zn 2+ , Co 2+ , Ni 2+ , Cd 2+ , Hg 2+ , and Cu 2+) were reversible. The dependence of the half-wave potentials of the Pb 2 + ion on the concentration of PPTA in the organic phase indicates that the ion transfer is facilitated by the formation of 1:2 (metal:ligand) complex in the organic phase with the association constant (lgβ2) of (17.1±0.2).
Fluorescent labeling of L-929 fibroblast cells was studied by using newly synthesized ligand whic... more Fluorescent labeling of L-929 fibroblast cells was studied by using newly synthesized ligand which was named as 2- N -methylamino-5-(pyrene-1-yl)-thiazole (ABS 40). The maximum fluorescence intensity of ABS 40 was detected at an excitation and emission wavelengths of 350 nm and 400 nm. Fluorescence intensity of the ligand was changed by the addition of DNA from calf thymus (CT-DNA) and human serum albumin (HSA). Both biomolecules and ABS 40 formed complexes that changed the fluorescence intensity of the ligand at the given wavelengths. Cytotoxicity tests were done with XTT analysis. L-929 fibroblast cells were cultured in the presence of ABS 40 to show cell labeling. Results showed that ABS 40 at 318 μM was labeled the cells at an excitation wavelength of 403.7 nm by using confocal microscopy. in vivo cell labeling was also confirmed by using Ct-DNA immobilized iron nanoparticles.
A novel calix[4]arene derivative containing benzothiazole azo groups at the upper rim was synthes... more A novel calix[4]arene derivative containing benzothiazole azo groups at the upper rim was synthesized as chromogenic chemosensor, and its binding and sensing properties with heavy metal ions (Pb(2+), Hg(2+), Ni(2+), Cd(2+), Cu(2+), Zn(2+), Co(2+), Fe(2+), Mn(2+), Cr(3+), Ag(+)) were investigated by UV-vis spectroscopy and voltammetric techniques. The results of spectroscopic and voltammetric experiments showed that the chromogenic chemosensor has high selectivity towards Hg(2+) ion over the other heavy metal ions. Moreover, it was shown that the interaction between Hg(2+) and the chromogenic chemosensor occurs by means of the benzothiazole azo groups at the upper rim by using differential pulse voltammetry. The stoichiometric ratio and the association constant were determined as 1:1 and (6.1+/-0.3)x10(5) L mol(-1) for the complex between Hg(2+) and the ionophore. Furthermore, we prepared a rapid test kit for early detection of Hg(2+) in aqueous environment in the concentration range of 1 x 10(-4) to 1 x 10(-2)M.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2014
h i g h l i g h t s New thiazole derivative have been synthesized and characterized. Complexation... more h i g h l i g h t s New thiazole derivative have been synthesized and characterized. Complexation behaviors for various anionic species investigated. It is a very good naked eye detection sensor for the fluoride anion.
Four new tripodal-benzimidazole derivatives were synthesized by Schiff base reaction between 2,4,... more Four new tripodal-benzimidazole derivatives were synthesized by Schiff base reaction between 2,4,6tris(p-formylphenoxy)-1,3,5-triazine (TRIPOD) and different diamine derivatives. The structures of the obtained compounds were identified by FT-IR, 1 H NMR, 13 C NMR and UV-vis spectral data, thermal analysis and elemental analysis. Electrochemical behaviors of the compounds were studied by cyclic voltammetry in DMF including 0.1 M [NBu 4 ] [PF 6 ]. The voltammograms showed peaks having similar characteristics except tripodal-benzimidazole including-NO 2 derivative. In addition, their antimicrobial activities were evaluated by using the standard disk diffusion method in dimethylformamide media. The activities were determined against 4 bacteria cultures by comparing to those of gentamycin.
The transfer of alkali and alkaline-earth metal ions facilitated by a calix[4]arene derivative, 2... more The transfer of alkali and alkaline-earth metal ions facilitated by a calix[4]arene derivative, 25,27-di [(2-ethoxy)benzaldehyde]-26,28-dihydroxy-5,11,17,23-tetra(tert-butyl) calix[4]arene (DBC4), across a water/1,2-dichloroethane (1,2-DCE) micro-interface supported at the tip of a micropipette was investigated. The well-defined voltammetric behavior was obtained only for Na + ion among the used metal ions by using the electrochemical methods. The measurements were performed when the bulk concentration of Na + ion in the aqueous phase is much higher than that of DBC4 in the organic phase, and vice versa. The diffusion coefficient of DBC4 in the DCE phase was calculated to be equal to (4.2 ± 0.2) Â 10 À6 cm 2 s À1. The logarithm of the association constant of DBC4-Na + complex having 1:1 stoichiometry in 1,2-DCE was determined as 3.99. The differential pulse voltammetry was used for amperometric detection of Na + ion in chloride medium. The results show that DBC4 can be used for many analytical applications such as ion recognition and fabrication of electrochemical sensor for Na + ion because of its good selectivity.
In this study, a novel azocalix[4]arene derivative, 5,11,17-tris[(1-naphtyl)azo]-25,26,27,28-tetr... more In this study, a novel azocalix[4]arene derivative, 5,11,17-tris[(1-naphtyl)azo]-25,26,27,28-tetrahydroxy -calix[4]arene (NAC4) bearing napthyl groups on the upper rim was synthesized. Its complexation behavior for alkali, alkaline-earth and various heavy metal ions (Li + , Na + , K + , Rb + , ...
Acetyldiphenyl ether and 4,4-diacetyldiphenyl ether were synthesized from diphenyl ether and acet... more Acetyldiphenyl ether and 4,4-diacetyldiphenyl ether were synthesized from diphenyl ether and acetyl chloride in the presence of AlCl3 used as catalyst. Subsequently, their keto oxime and glyoxime derivatives were prepared. The metal complexes of the glyoximes such as Cu(II), Ni(II) and Co(II) were also prepared. The structures of these ligands and their complexes were identified by FT-IR, 1 H NMR and 13 C NMR spectral data, elemental analysis and magnetic measurements.
In this study, some thiazole-based pyrrolidine derivatives were synthesized, characterized by FT-... more In this study, some thiazole-based pyrrolidine derivatives were synthesized, characterized by FT-IR and 1H NMR spectroscopic techniques, and evaluated as potential antibacterial agents. Their antibacterial activities were evaluated by broth microdilution method and expressed as minimum inhibitory concentration; against Escherichia coli, Salmonella typhimurium, Bacillus cereus, and Staphylococcus aureus. Cytotoxicity studies of synthesized compounds were also conducted to minimize the toxic effects on healthy mammalian cells. From synthesized compounds, 4-F-phenyl derivative compound (11) has been found to inhibit Gram-positive bacteria with minimum toxicity selectively.
4-(Chloroacetyl)diphenyl ether (I) was synthesized from chloroacetyl chloride and diphenyl ether ... more 4-(Chloroacetyl)diphenyl ether (I) was synthesized from chloroacetyl chloride and diphenyl ether in the presence of AlCl3 as catalyst in a Friedel-Crafts reaction. Subsequently, its keto oxime (II) derivative was prepared. Then 3 new substituted 4-(alkylaminoisonitrosoacetyl)diphenyl ether ligands derived from 4-(phenoxy)phenyloxylohydroxymoyl chloride and corresponding amines were synthesized. The following aromatic and aliphatic amines were used for the ligands ethanolamine, 2-amino-4-methylphenol, and
The oxidation of some cyanocycloheptatrienes with CrO3 and pyridine was investigated and a few ne... more The oxidation of some cyanocycloheptatrienes with CrO3 and pyridine was investigated and a few new nitrile functionalised benzotropone derivatives were obtained. Photooxygenation reaction of these products was also studied. The structures of the formed products were determined on the basis of NMR spectroscopy and the formation mechanism of unusual products was discussed. Human carbonic anhydrase isoenzymes I, and II (hCA I and hCA II) inhibition properties of nitrile functionalized new benzotropone derivatives were also studied. Both CA isozymes were inhibited in the low micromolar range by these nitrile functionalized benzotropone analogues. The newly synthesized benzotropone derivatives showed inhibition constants in the sub-micromolar range (2.51-4.06μM). The best hCA I inhibition was observed in 5H-benzocycloheptene-7-carbonitrile (Ki: 2.88±0.86μM). On the other hand, 5-oxo-5H-benzocycloheptatriene-7-carbonitrile showed the powerful inhibitory effect against hCA II (Ki: 2.51±0.34μM).
The ESR spectra analysis indicated the formation of two identical radicals on irradiated 4,4 0-bi... more The ESR spectra analysis indicated the formation of two identical radicals on irradiated 4,4 0-bis(chloroacetyl)diphenylether polycrystal. It was determined that the produced radical structures on 4,4 0-bis(chloroacetyl)diphenylether irradiated were stable.
Journal of Inclusion Phenomena and Macrocyclic Chemistry, 2007
A doubly fused porphyrin has been synthesized by two successive cyclization reactions. The first ... more A doubly fused porphyrin has been synthesized by two successive cyclization reactions. The first meso-phenyl group was fused by an intramolecular Cadogan reaction leading to an enamine-functionalized porphyrin. After Vilsmeier-Haack formylation of the nickel enaminoporphyrin, an intramolecular Friedel-Crafts reaction followed by dehydration of the intermediate alcohol afforded the doubly fused aromatic nickel porphyrin, which could be demetalated. The free base
Journal of Inclusion Phenomena and Macrocyclic Chemistry, 2007
4-(Chloroacetyl)diphenyl thioether (1) was synthesized from chloroacetyl chloride and diphenyl th... more 4-(Chloroacetyl)diphenyl thioether (1) was synthesized from chloroacetyl chloride and diphenyl thioether in the presence of AlCl 3 as catalyst in a Friedel-Crafts reaction. Subsequently, its keto oxime (2) and glyoxime (3) derivatives were prepared. N-(4 0-Benzo[15crown-5]thiophenoxyphenylaminoglyoxime (H 2 L) and its sodium chloride complex (H 2 L Á NaCl) were prepared from 4-(thiophenoxy)chlorophenylglyoxime (3), 4 0-aminobenzo[15-crown-5] and sodium bicarbonate or sodium bicarbonate and sodium chloride. Ni(II), Co(II) and Cu(II) complexes of H 2 L and H 2 L Á NaCl have a metal-ligand ratio of 1:2 and the ligand coordinates through the two N atoms, as do most of the vic-dioximes. The BF 2-capped Ni(II) mononuclear complex of the vic-dioxime was prepared. The macrocyclic ligands and their transition metal complexes were characterized on the basis of FT-IR, 1 H NMR, 13 C NMR spectroscopy and elemental analyses data.
2,4,6-tris(4-hydroxybenzimino)-1,3,5-triazine [1,2] (III) have been synthesized by the reaction o... more 2,4,6-tris(4-hydroxybenzimino)-1,3,5-triazine [1,2] (III) have been synthesized by the reaction of 1 equiv melamine and three equiv 4-hydroxybenzaldehyde, and characterized by means of elemental anal-ysis, 1H-NMR (nuclear magnetic resonance spectroscopy), Fourier ...
A new silica gel compound modified 4,4&am... more A new silica gel compound modified 4,4'-oxy-bis(chlorophenylglyoxime) (CPGO) was synthesized and characterized by infrared spectroscopy, elemental analysis and thermogravimetric analysis. The sorption capacity of such a matrix towards Co(II), Ni(II) and Cu(II) from aqueous solutions was studied. The optimum pH values for the separation of these divalent cations on the sorbent were 5.0, 6.0 and 6.0 for Cu, Co and Ni, respectively. The process of metal separation was followed by batch method, and fitted to a Langmuir and Freundlich sorption isotherms. The maximum sorption capacities (0.055, 0.042, and 0.034 mmol g(-1)) were found from the Langmuir equation and the enthalpies of binding were 44.96, 71.63, and 68.14 kJ mol(-1) for Cu, Co and Ni, respectively. The other thermodynamic parameters calculated from the adsorption results were used to explain the mechanism of the adsorption. For example, the Gibbs free energies of binding agree with the spontaneity of the proposed reaction between cations and basic centers.
4,4 -Bis(chloroacetyl)diphenyl thioether (HL) was synthesized from chloroacetyl chloride and diph... more 4,4 -Bis(chloroacetyl)diphenyl thioether (HL) was synthesized from chloroacetyl chloride and diphenyl thioether in the presence of AlCl3 as catalyst in a Friedel-Crafts reaction. Subsequently, its keto oxime (H2L) and glyoxime (H4L) derivatives were also prepared. ...
In addition to the synthetic aspects, the chemistry of endoperoxides has fascinated organic chemi... more In addition to the synthetic aspects, the chemistry of endoperoxides has fascinated organic chemists for long years. 7 As a direct consequence of this, we have been interested in the oxidation reactions of different tropone and tropolone derivatives in order to develop new synthetic strategies ...
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