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Full-Text Articles in Physical Sciences and Mathematics

Electrochemistry Of Fe(Iv) And Mn(Iv) Corroles Containing Meso-Dichlorophenyl Substituents And The Use Of These Compounds As Catalysts For The Electroreduction Of Dioxygen In Acid Media, Lina Ye, Zhongping Ou, Deying Meng, Mingzhu Yuan, Yuanyuan Fang, Karl M. Kadish Jan 2014

Electrochemistry Of Fe(Iv) And Mn(Iv) Corroles Containing Meso-Dichlorophenyl Substituents And The Use Of These Compounds As Catalysts For The Electroreduction Of Dioxygen In Acid Media, Lina Ye, Zhongping Ou, Deying Meng, Mingzhu Yuan, Yuanyuan Fang, Karl M. Kadish

Turkish Journal of Chemistry

Two meso-dichlorophenyl substituted metallocorroles were synthesized and characterized as to their electrochemical and spectroelectrochemical properties in dichloromethane, benzonitrile, and pyridine containing 0.1 M tetra-n-butylammonium perchlorate (TBAP) as supporting electrolyte. The examined compounds are represented as (Cl_2Ph)_3CorFe^{IV}Cl and (Cl_2Ph)_3CorMn^{IV}Cl where (Cl_2Ph)_3Cor is the trianion of 5,10,15-tri(2,4-dichlorophenyl)corrole. Each metallocorrole was examined as to its catalytic activity for the electoreduction of dioxygen when coated on an edge-plane pyrolytic graphite electrode in 1.0 M HClO_4. Cyclic voltammetry combined with linear sweep voltammetry at a rotating disk electrode (RDE) and a rotating ring disk electrode (RRDE) was utilized to evaluate the catalytic activity for the …


Nature Of Second-Order Nonlinear Optical Response In Phthalocyanine Derivatives: A Density Functional Theory Study, Chiming Wang, Chao Chen, Qingqi Zhang, Dongdong Qi, Jianzhuang Jiang Jan 2014

Nature Of Second-Order Nonlinear Optical Response In Phthalocyanine Derivatives: A Density Functional Theory Study, Chiming Wang, Chao Chen, Qingqi Zhang, Dongdong Qi, Jianzhuang Jiang

Turkish Journal of Chemistry

Density functional theory was employed to investigate a series of phthalocyanine derivatives, discovering the limitation when the expansion of the conjugated system was employed to improve the hyper-Rayleigh scattering response coefficient. Furthermore, an unusually C_{\infty v}-type octupolar population was found by electrostatic potential analysis. In addition, the dynamic and static hyper-Rayleigh scattering responses (\beta_{HRS}) were simulated using the coupled perturbed density functional theory, showing an increasing dynamic \beta_{HRS} value along with an increase in incident light energy.


Synthesis And Characterization Of Tetra-Substituted Titanium(Iv) Phthalocyanines With Axial Ligand, Deni̇z Kutlu Tarakci, İlke Gürol Jan 2014

Synthesis And Characterization Of Tetra-Substituted Titanium(Iv) Phthalocyanines With Axial Ligand, Deni̇z Kutlu Tarakci, İlke Gürol

Turkish Journal of Chemistry

In this paper, the synthesis and characterization of peripheral tetra-2-(2-ethyloxyethyloxy)ethyloxy substituted oxo-titanium phthalocyanines (TiOPcs) are reported. The reaction of 2,2,3,3-tetrafluoropropoxy substituted and [2-(2-ethoxyethoxy)ethoxy] substituted TiOPcs (1 and 3) with 4-[(6-hydroxyhexyl)oxy]benzene-1,2-diol as a strongly chelating oxygen donor ligand is described. Compounds 1a and 3a bearing the hydroxyl group as an axial ligand of the bulky group are converted into a thiol group (1c and 3c). The new compounds are characterized by elemental analysis, FT-IR, ^1H NMR, and mass spectrometry. While the fluoropropoxy substituted TiOPc has good solubility in polar solvents such as acetone and THF, the other TiOPc is soluble in …


Novel Metal-Free And Metallophthalocyanines Containing Four 21-Membered Pentathiadiaza Macrocycles: Synthesis, Characterization, And Study Of Aggregation Properties, Hali̇l Zeki̇ Gök, Berna Farsak, Hülya Keleş, Mustafa Keleş Jan 2014

Novel Metal-Free And Metallophthalocyanines Containing Four 21-Membered Pentathiadiaza Macrocycles: Synthesis, Characterization, And Study Of Aggregation Properties, Hali̇l Zeki̇ Gök, Berna Farsak, Hülya Keleş, Mustafa Keleş

Turkish Journal of Chemistry

Metal-free phthalocyanine 3 and its metallophthalocyanine derivatives 4, 5, and 6 (M = Zn, Co, and Ni) substituted with four 21-membered pentathiadiaza macrocycles were synthesized and their structures identified by elemental analysis, IR, ^1H NMR, mass, and UV-Vis spectroscopy techniques. The aggregation properties of phthalocyanines 4, 5, and 6 were investigated in different solvents and at different concentrations of dimethylformamide.


Synthesis And Characterization Of Novel 2-{[2-(Dimethylamino)Ethyl](Methyl)Amino} Ethoxy-Substituted Metallophthalocyanines, Hi̇lal Zengi̇n, Hacer Yasemi̇n Yeni̇lmez, Ayfer Kalkan Burat, Zehra Altuntaş Bayir Jan 2014

Synthesis And Characterization Of Novel 2-{[2-(Dimethylamino)Ethyl](Methyl)Amino} Ethoxy-Substituted Metallophthalocyanines, Hi̇lal Zengi̇n, Hacer Yasemi̇n Yeni̇lmez, Ayfer Kalkan Burat, Zehra Altuntaş Bayir

Turkish Journal of Chemistry

The synthesis of novel, symmetrical, tetrasubstituted metallophthalocyanines (cobalt, zinc, and copper) bearing four 2-{[2-(dimethylamino)ethyl](methyl)amino} ethoxy units was reported. The dinitrile derivative was converted into the water-soluble quaternized product by its reaction with methyl iodide. The quaternized zinc phthalocyanine was obtained from the reaction of the water-soluble dinitrile derivative with zinc acetate. The structures of the newly synthesized molecules were proposed according to elemental analysis, ^1H NMR, FT-IR, and UV-Vis spectral data.


Synthesis, Characterization, And Photophysical And Photochemical Properties Of 3-(4-Phenyloxy)Coumarin Containing Metallo- And Metal-Free Phthalocyanines, Nurullah Kartaloğlu, Ali̇ye Asli Esenpinar, Mustafa Bulut Jan 2014

Synthesis, Characterization, And Photophysical And Photochemical Properties Of 3-(4-Phenyloxy)Coumarin Containing Metallo- And Metal-Free Phthalocyanines, Nurullah Kartaloğlu, Ali̇ye Asli Esenpinar, Mustafa Bulut

Turkish Journal of Chemistry

The synthesis of novel zinc, cobalt, indium, and metal-free phthalocyanines carrying four 3-(4-phenyloxy)couma- rins in the periphery/nonperiphery were prepared by cyclotetramerization of 3-[4-(3,4-dicyanophenyloxy)phenyl]coumarin (2)/3-[4-(2,3- dicyanophenyloxy)phenyl]coumarin (3). The novel chromogenic compounds were characterized by elemental analysis, ^1H NMR, mass spectra, F-IR, and UV-vis spectral data. The effects of the coumarin units on the zinc, indium, and metal-free phthalocyanine complexes (2a/3a, 2c/3c, 2d/3d) were also investigated.


Synthesis And Spectral And Thermal Characterization Of New Metal-Free And Metallophthalocyanines: Investigation Of Their Photophysical, Photochemical, And Thin Film Properties, Eli̇f Çelenk Kaya, Mahmut Durmuş, Ekrem Yanmaz, Hali̇t Kanteki̇n Jan 2014

Synthesis And Spectral And Thermal Characterization Of New Metal-Free And Metallophthalocyanines: Investigation Of Their Photophysical, Photochemical, And Thin Film Properties, Eli̇f Çelenk Kaya, Mahmut Durmuş, Ekrem Yanmaz, Hali̇t Kanteki̇n

Turkish Journal of Chemistry

Novel tetrasubstituted metal-free (2), zinc (II) (3), cobalt (II) (4), and copper (II) (5) phthalocyanines bearing 2-phenylethanolate groups on the peripheral positions were synthesized by the cyclotetramerization reaction of the phthalonitrile derivative 1. The new compounds were characterized by a combination of IR, ^1H NMR, ^{13}C NMR, UV-Vis, elemental analysis, and MS spectra data. The thermal stabilities of the phthalocyanine compounds were determined by thermogravimetric analysis. For metal-free (2) and zinc (3) phthalocyanines, photochemical (photodegradation and singlet oxygen quantum yields) and photophysical (fluorescence quantum yields and fluorescence lifetimes) properties were analyzed in dimethylsulfoxide (DMSO). The cobalt (4) and copper (5) …


Microwave-Assisted Synthesis Of Novel Nonperipherally Substituted Metallophthalocyanines Bearing (7-(Trifluoromethyl)Quinolin-4-Yl)Oxy Groups, Di̇dem Evren, Hacer Yasemi̇n Yeni̇lmez, Ayfer Kalkan Burat Jan 2014

Microwave-Assisted Synthesis Of Novel Nonperipherally Substituted Metallophthalocyanines Bearing (7-(Trifluoromethyl)Quinolin-4-Yl)Oxy Groups, Di̇dem Evren, Hacer Yasemi̇n Yeni̇lmez, Ayfer Kalkan Burat

Turkish Journal of Chemistry

The synthesis, characterization, and spectroscopic properties of novel nonperipherally tetrasubstituted metallophthalocyanines (zinc, cobalt, copper, manganese, and indium) bearing 4 (7-(trifluoromethyl)quinolin-4-yl)oxy units has been reported. The new compounds have been characterized using UV-Vis, IR, ^1H NMR, ^{13}C NMR, ^{19}F NMR, and mass spectroscopic data. The absorption properties of these new complexes were compared to those of peripherally substituted phthalocyanine derivatives. Based on the structural, spectroscopic, and absorption studies, it was found that the substitution effect altered the electronic structures significantly. The results provide useful information to understand the effect of peripheral or nonperipheral substitution on the properties of this macrocyclic ring. …


Immobilized Metal Ion Affinity Nanospheres For \Alpha-Amylase Immobilization, Tülden Kalburcu, Müni̇re Nalan Tüzmen, Si̇nan Akgöl, Adi̇l Deni̇zli̇ Jan 2014

Immobilized Metal Ion Affinity Nanospheres For \Alpha-Amylase Immobilization, Tülden Kalburcu, Müni̇re Nalan Tüzmen, Si̇nan Akgöl, Adi̇l Deni̇zli̇

Turkish Journal of Chemistry

Immobilized metal chelate affinity chromatography (IMAC) support was practiced for \alpha-amylase immobilization. Poly(hydroxyethylmethacrylate-methacryloylamidotryptophan)-Ni^{2+} [p(HEMA-MAT)-Ni^{2+}] nanospheres, average diameter 100 nm, were produced by surfactant free emulsion polymerization. Characterizations of p(HEMA-MAT)-Ni^{2+} nanospheres were carried out by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (SEM). In addition, average particle size, size distribution, and surface charge were specified. The amount of N-methacryloylamidotryptophan (MAT) incorporated to polymer was determined as 1.95 mmol/g polymers by using nitrogen stoichiometry. The specific surface areas of poly(hydroxyethylmethacrylate) [p(HEMA)] and p(HEMA-MAT) nanospheres were calculated as 1856 m^2/g and 1914 m^2/g, respectively. Protein adsorption increased with increasing initial protein …


Nh-Acidities And Hammett Correlation Of 3-Para Substituted Phenyl-1,2,4-Oxadiazol-5(4h)-Ones And 1,2 \Lambda^43,5-Oxathiadiazole 2-Oxides In Nonaqueous Media, Nedi̇me Dürüst, Yaşar Dürüst, Emi̇ne Özge Gözlükaya Jan 2014

Nh-Acidities And Hammett Correlation Of 3-Para Substituted Phenyl-1,2,4-Oxadiazol-5(4h)-Ones And 1,2 \Lambda^43,5-Oxathiadiazole 2-Oxides In Nonaqueous Media, Nedi̇me Dürüst, Yaşar Dürüst, Emi̇ne Özge Gözlükaya

Turkish Journal of Chemistry

NH acidities of some 3-(p-substitutedphenyl)-1,2,4-oxadiazol-5(4H)-ones and 4-(p-substitutedphenyl)-1,2 \lambda^43,5-oxathiadiazole 2-oxides were determined in methanol by means of potentiometric titration with sodium methoxide. pK_a values of the title compounds calculated from the potentiometric data were interpreted on the basis of structural effects caused by para-substituted groups on the phenyl ring by plotting pK_a values versus Hammett \sigma_p^+ constants, which gave excellent linear correlations.


A Combined First Principles Tddft And Experimental Study On The Uv-Vis Spectra Properties Of M(P-Nitrophenyl Azo Resorcinol)_3 Complexes (M: Fe, Cr), Tuğba Ari̇fi̇oğlu, Meli̇s Efeçinar, Nuray Şatiroğlu Jan 2014

A Combined First Principles Tddft And Experimental Study On The Uv-Vis Spectra Properties Of M(P-Nitrophenyl Azo Resorcinol)_3 Complexes (M: Fe, Cr), Tuğba Ari̇fi̇oğlu, Meli̇s Efeçinar, Nuray Şatiroğlu

Turkish Journal of Chemistry

UV-Vis absorption data of p-nitrophenyl azo resorcinol (Magneson I) and its 2 Fe(III) and Cr(III) complexes were investigated both experimentally and theoretically. The geometries were optimized at BP86/TZVP level. The most stable spin states were computed as doublet and quartet for Fe(magneson)_3 and Cr(magneson)_3 complexes, respectively. Time-dependent density functional theory (TDDFT) was employed to explore the absorption spectra properties, whereas the solvent effects were taken into account using the polarizable continuum model (PCM). The M06, B3LYP, and PBE0 hybrid functionals together with TZVP/LANL2TZ basis sets were used for comparing the results with experimental data. The theoretical analysis of electronic structure …


Comparison Of Chelating Ability Of No-, Ns-, Ons-, And Ono-Type Schiff Base Derivatives And Their Stability Constants Of Bis-Complexes With Copper(Ii), Hasan Atabey, Esra Findik, Hayati̇ Sari, Mustafa Ceylan Jan 2014

Comparison Of Chelating Ability Of No-, Ns-, Ons-, And Ono-Type Schiff Base Derivatives And Their Stability Constants Of Bis-Complexes With Copper(Ii), Hasan Atabey, Esra Findik, Hayati̇ Sari, Mustafa Ceylan

Turkish Journal of Chemistry

The present study includes important findings relating to the number of donor atoms, species of ligands, and stabilities of complexes. Stabilities of complexes between Cu(II) ion and NO-, NS-, ONS-, and ONO-type Schiff bases were compared. Acid-base properties of the Schiff bases were explained at 25 \pm 0.1 °C and ionic strength (I) of 0.1 M supported by NaCl. The Hyperquad computer program was used for calculation of dissociation and stability constants. The overall stability constants of their Cu(II) complexes were calculated and the various formed complexes between the Schiff bases with Cu(II) ion formulated as CuL_2, CuHL_2, CuH_2L_2, and …


On The Peculiar Reactivity Of A C,N-Annelated Isoindole Core, Iaroslav Baglai, Valerie Maraval, Zoia Vsevolodivna Voitenko, Carine Duhayon, Yulian Mihailovich Volovenko, Remi Chauvin Jan 2014

On The Peculiar Reactivity Of A C,N-Annelated Isoindole Core, Iaroslav Baglai, Valerie Maraval, Zoia Vsevolodivna Voitenko, Carine Duhayon, Yulian Mihailovich Volovenko, Remi Chauvin

Turkish Journal of Chemistry

C-, N-, and/or O-methylation products were generated from 11H-isoindolo[2,1-a]quinazoline-5-one upon treatment with NaH followed by iodomethane under air, and possible recrystallization from methanol. Two products were fully characterized by NMR and X-ray diffraction analysis. In accordance with the HSAB principle, this soft methylating agent (MeI) leads mainly to the C,C-dimethylated product 11,11-dimethyl-11H-isoindolo[2,1-a]quinazoline-5-one, which was previously not observed, beside the N-methylated product, in a procedure using methyl tosylate as a hard methylating agent of the same substrate in the initial absence of a base. A mechanism is finally proposed for the formation of methyl 2-(3-methyl-4-oxo-3,4-dihydroquinazolin-2-yl)benzoate as an oxidation side product.


Experimental Investigation Of Drag Reduction Effects Of Polymer Additives On Turbulent Pipe Flow Using Ultrasound Doppler Velocimetry, Şeri̇fe Zeybek Vural, Göknur Bayram, Yusuf Uludağ Jan 2014

Experimental Investigation Of Drag Reduction Effects Of Polymer Additives On Turbulent Pipe Flow Using Ultrasound Doppler Velocimetry, Şeri̇fe Zeybek Vural, Göknur Bayram, Yusuf Uludağ

Turkish Journal of Chemistry

Drag reduction in fully developed turbulent pipe flow with 4 concentrations (200 to 500 wppm or mg/kg) of low molecular weight sodium carboxymethylcellulose (CMC) in aqueous solutions was investigated experimentally. Drag reduction was determined by pressure drop measurements. Maximum drag reduction achieved was 22% using 500 wppm CMC solution. To observe the impact of the presence of CMC on the flow, ultrasound Doppler velocimetry (UDV) was employed to monitor the instantaneous velocity distributions. Experimental measurements were used to calculate Fanning friction factor and radial distributions of the axial time-averaged velocity, velocity fluctuation (turbulent intensity), and eddy viscosity. Two impacts of …


Self-Condensation Reactions Of Acyl Phosphonates: Synthesis Of Tertiary O-Protected \Alpha-Hydroxyphosphonates, Serkan Eymur, Mehmet Göllü, Ayhan Sitki Demi̇r Jan 2014

Self-Condensation Reactions Of Acyl Phosphonates: Synthesis Of Tertiary O-Protected \Alpha-Hydroxyphosphonates, Serkan Eymur, Mehmet Göllü, Ayhan Sitki Demi̇r

Turkish Journal of Chemistry

The self-condensation reaction of benzoyl dialkyl phosphonates was developed using cyanide ion as catalyst, affording versatile tertiary O-protected \alpha-hydroxy phosphonates in moderate yield.


Synthesis And Antimicrobial Activity Of Novel 2-[4-(1h-Benzimidazol-1-Yl)Phenyl]-1h-Benzimidazoles, Mehmet Alp, Ali̇ Hakan Göker, Nurten Altanlar Jan 2014

Synthesis And Antimicrobial Activity Of Novel 2-[4-(1h-Benzimidazol-1-Yl)Phenyl]-1h-Benzimidazoles, Mehmet Alp, Ali̇ Hakan Göker, Nurten Altanlar

Turkish Journal of Chemistry

A new class of 2-[4-(1H-benzimidazol-1-yl)phenyl]-1H-benzimidazoles (13--22) were synthesized via cyclocondensation reaction of the substituted 1,2-phenylenediamines (1, 4--12) and 1-(4-formylpheny)-1H-benzimidazole (3). The synthesized compounds were evaluated for antibacterial and antifungal activities against S. aureus, methicillin-resistant Staphylococcus aureus (MRSA), and Candida albicans by the tube dilution method. Compounds 13, 15, 18, 20, and 21 have moderate antifungal activity against C. albicans.