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Articles 10651 - 10680 of 11371
Full-Text Articles in Entire DC Network
Solvent-Free Preparation Of Primary Carbamates, Ali Reza Modarresi-Alam, Mohsen Rostamizadeh, Parisa Najafi
Solvent-Free Preparation Of Primary Carbamates, Ali Reza Modarresi-Alam, Mohsen Rostamizadeh, Parisa Najafi
Turkish Journal of Chemistry
Herein, we describe a simple and efficient method for the conversion of compounds containing a hydroxyl group to primary carbamates at room temperature with excellent yield and purity, and without any epimerization, in the absence of solvent.
Investigation Of The Cation Complexation By Macrocyclic Ethers Using ^{13}C Nmr Spin--Lattice Dipolar Relaxation Time Measurements, Çakil Erk, Matthias Heydenreich, Erich Kleinpeter
Investigation Of The Cation Complexation By Macrocyclic Ethers Using ^{13}C Nmr Spin--Lattice Dipolar Relaxation Time Measurements, Çakil Erk, Matthias Heydenreich, Erich Kleinpeter
Turkish Journal of Chemistry
The binding constants (K_a) of [18]crown-6 ether with Na^+ , K^+, and Ba^{2+} thiocyanates were determined by ^{13}C{^1H} NMR spin--lattice dipolar relaxation time measurements. The observed relaxation times (T_{obs}) for ^{13}C nuclei are dependent upon the relaxation times of the complexed (T_{1a}) and free crown ether (T_{1f}), and were measured in [D4]methanol using inversion--recovery measurements in the extreme narrowing limit (75 MHz). The observed ^{13}C relaxation times of the metal complexes were found to be smaller than those of the cation-free macrocyclic ether due to reduced internal flexibility of the macrocycles in the complexes. The relationship 1/T_{obs} = P_a/T_{1a} + …
Synthesis And Antimicrobial Activity Of Some New 3-Substituted Benzyl-5-(4-Chloro-2-Piperidin-1yl-Thiazole-5-Yl-Methylene)-Thiazolidine-2,4-Dione Derivatives, Meltem Ceylan Ünlüsoy, Oya Bozdağ Dündar, Nurten Altanlar, Rahmi̇ye Ertan
Synthesis And Antimicrobial Activity Of Some New 3-Substituted Benzyl-5-(4-Chloro-2-Piperidin-1yl-Thiazole-5-Yl-Methylene)-Thiazolidine-2,4-Dione Derivatives, Meltem Ceylan Ünlüsoy, Oya Bozdağ Dündar, Nurten Altanlar, Rahmi̇ye Ertan
Turkish Journal of Chemistry
A new series of thiazolyl thiazolidine-2,4-dione (Va-f) were synthesized and their structures were elucidated by IR, ^1H-NMR, mass spectra and elementary analysis. The synthesized compounds were tested for their antimicrobial activities against Candida albicans, Staphylococcus aureus, Bacillus subtilis and Escherichia coli. Compounds Va-b, Vd-f showed high activity against Escherichia coli comparable to ampicillin.
Metal Complexes Of Schiff Bases: Preparation, Characterization, And Biological Activity, Gehad Genidy Mohamed, Mohamed Mohamed Omar, Ahmed Mohamed Hindy
Metal Complexes Of Schiff Bases: Preparation, Characterization, And Biological Activity, Gehad Genidy Mohamed, Mohamed Mohamed Omar, Ahmed Mohamed Hindy
Turkish Journal of Chemistry
Metal complexes of Schiff bases derived from 2-furancarboxaldehyde and o-phenylenediamine (L^1), and 2-thiophenecarboxaldehyde and 2-aminothiophenol (HL^2) are reported and characterized based on elemental analyses, IR ^1H NMR, solid reflectance, magnetic moment, molar conductance, and thermal analysis (TGA). The ligand dissociation, as well as the metal-ligand stability constants were calculated, pH-metrically, at 25 °C and ionic strength \mu = 0.1 (1 M NaCl). The complexes are found to have the formulae [M(L^1)(H_2O)_2](Cl)_n \cdot yH_2O (where M = Fe(III), Ni(II), Cu(II); n = 2-3, y = 2-4); [M(L^1)](X)_2 \cdot yH_2O (where M = Co(II), Zn(II), UO_2(II), X = Cl, AcO or NO_3, …
Online Viscosity Measurement Of Complex Solutions Using Ultrasound Doppler Velocimetry, Volkan Köseli̇, Şeri̇fe Zeybek, Yusuf Uludağ
Online Viscosity Measurement Of Complex Solutions Using Ultrasound Doppler Velocimetry, Volkan Köseli̇, Şeri̇fe Zeybek, Yusuf Uludağ
Turkish Journal of Chemistry
A new method to measure the viscosity of non-Newtonian fluids over a wide range of shear rates in a short period of time is presented. The technique is based on the measurement of the velocity profile in a pipe flow using ultrasound Doppler velocimetry (UDV), which is a non-invasive method, and simultaneously determining the pressure drop. The velocity profile is used to obtain shear rate distribution, while the pressure drop is used to calculate the shear stress distribution. By taking the ratio of these quantities at a radial position, local viscosity can be obtained within the shear rate range in …
Secondary Metabolites From Euphorbia Helioscopia And Their Vasodepressor Activity, Asli Barla, Hüsni̇ye Bi̇rman, Şükran Kültür, Sevi̇l Öksüz
Secondary Metabolites From Euphorbia Helioscopia And Their Vasodepressor Activity, Asli Barla, Hüsni̇ye Bi̇rman, Şükran Kültür, Sevi̇l Öksüz
Turkish Journal of Chemistry
From the aerial parts of Euphorbia helioscopia L. (Euphorbiaceae), a jatrophane diterpene ester, 5,11-jatrophadiene-3-benzoyloxy-7,9,14-tri-acetyloxy-15-ol and 2 lupane derivatives, lup-20(29)-ene-3-acetate and lup-20(29)-ene-3-palmitate, together with common triterpenoids of Euphorbiaceae, 24-methylene cycloartanol, 24-methylenecycloart-3-one, cycloartanol, and stigmast-4-ene-3-one were isolated. The last compounds, lup-20(29)-ene-3-acetate, 24-methylene cycloartanol, 24-methylenecycloart-3-one, cycloartanol, and stigmast-4-ene-3-one, were isolated for the first time from E. helioscopia}. The fractions and the isolates were tested for their vasodepressor effects using Wistar Albino rats, and 5,11-jatrophadiene-3-benzoyloxy-7,9,14-tri-acetyloxy- 15-ol, lup-20(29)-ene-3-acetate, and stigmast-4-ene-3-one were found to possess relevant activity. The structures of all of the compounds were identified with high field spectroscopic methods. The detailed spectroscopic data of …
Synthesis And Spectroscopic Characterization Of Biologically Active Triarylantimony(V) Carboxylates Containing Germanium, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Khadija Shahid, Farnaz Malik
Synthesis And Spectroscopic Characterization Of Biologically Active Triarylantimony(V) Carboxylates Containing Germanium, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Khadija Shahid, Farnaz Malik
Turkish Journal of Chemistry
A new series of bimetallic (Ge and Sb) compounds (1-7) was synthesized and characterized by elemental analyses, FT-IR, multinuclear NMR (^1H, ^{13}C) spectroscopy and mass spectrometry. These techniques not only confirmed the formation of the compounds, but also revealed their trigonal bipyramidal geometry around antimony(V). Selected compounds were screened against different pathogens and showed promising antibacterial and antifungal activities.
A Novel Approach To The Hydrothermal Synthesis Of Anatase Titania Nanoparticles And The Photocatalytic Degradation Of Rhodamine B, Murat Akarsu, Meltem Asi̇ltürk, Funda Sayilkan, Nadi̇r Ki̇raz, Ertuğrul Arpaç, Hi̇kmet Sayilkan
A Novel Approach To The Hydrothermal Synthesis Of Anatase Titania Nanoparticles And The Photocatalytic Degradation Of Rhodamine B, Murat Akarsu, Meltem Asi̇ltürk, Funda Sayilkan, Nadi̇r Ki̇raz, Ertuğrul Arpaç, Hi̇kmet Sayilkan
Turkish Journal of Chemistry
A novel approach was developed for the synthesis of high-dispersed anatase nano-TiO_2 by a hydrothermal process without solvent at 200 °C in 1 h. It was characterized using XRD, TEM, BET and elemental analysis. Nanoparticle-TiO_2 was used as a photocatalyst by considering complete degradation of Rhodamine B (RB) dye. The photocatalytic reaction parameters such as photocatalyst amount, irradiation time and dye concentration were optimized and it was found that 0.125 wt% catalyst in 30 mg/L of RB aqueous solution is adequate for full degradation of RB in 50 min with 770 W/m^2 irradiation power. Photocatalytic activity of the nanoparticle-TiO_2 was …
Effect Of Surfactants On Response Of Promethazine Pvc-Membranes, Mohsen M. Zareh, Raga E. Shohiab, Mostafa Abd-El-Fatah
Effect Of Surfactants On Response Of Promethazine Pvc-Membranes, Mohsen M. Zareh, Raga E. Shohiab, Mostafa Abd-El-Fatah
Turkish Journal of Chemistry
The effect of surfactants (cationic, anionic and non-ionic) on the performance of plastic membrane promethazine electrodes was studied. Three electrodes with membranes containing either sodium tetraphenylborate, sodium tetraphenylborate + 18-crown-6, or 18-crown-6 were prepared. The cationic and the anionic surfactants exhibited potential shifts and a super-Nernstian slope of the calibration graphs. The non-ionic surfactant did not cause alterations in the calibration graphs. The effect of surfactants' concentrations was investigated. The performance characteristics of these electrodes were studied. The slopes of the calibration graphs of the 3 electrodes were 54.4, 54.9 and 48.4 mV/decade. The rectilinear ranges were 2 x 10^{-5}-10^{-2}, …
Trace Element Determination In Brassica Oleraceae Var. Acephale By Differential Pulse Polarography, Güler Somer, Arzu Nakişci Ünlü, Şükrü Kalayci, Ferat Şahi̇n
Trace Element Determination In Brassica Oleraceae Var. Acephale By Differential Pulse Polarography, Güler Somer, Arzu Nakişci Ünlü, Şükrü Kalayci, Ferat Şahi̇n
Turkish Journal of Chemistry
A fast and simple differential pulse polarographic (DPP) method for the determination of trace elements in a certain form of cabbage is described. This vegetable is commonly used as food in Turkey, especially in the Black Sea region. Using DPP polarograms of wet digested cabbage samples (leaf) in pH 2 and 4 acetate buffer Mo, Cr, Se, Pb, As and Zn quantities were determined. The best separation and determination condition for Cu and Fe was in EDTA at pH 6.5, and for Ni and Zn it was ammonia buffer at pH 9.8. The trace element quantities in digested leaf samples …
Electrochemical Synthesis Of N-Methylpyrrole And N-Methylcarbazole Copolymer On Carbon Fiber Microelectrodes, And Their Characterization, A. Sezai̇ Saraç, Erkan Doğru, Murat Ateş, Eli̇f Altürk Parlak
Electrochemical Synthesis Of N-Methylpyrrole And N-Methylcarbazole Copolymer On Carbon Fiber Microelectrodes, And Their Characterization, A. Sezai̇ Saraç, Erkan Doğru, Murat Ateş, Eli̇f Altürk Parlak
Turkish Journal of Chemistry
Copolymer films of N-methylpyrrole (N-MPy) and N-methylcarbazole (N-MCz) were synthesized electrochemically onto single carbon fiber microelectrodes (CFMEs). Deposition conditions on the carbon fiber, influence of the monomer concentrations on the copolymerization of P[N-methylpyrrole-co-N-methylcarbazole] P[N-MPy-co-N-MCz], and the electrochemistry of the resulting homopolymer and copolymers were studied using cyclic voltammetry, FTIR-ATR, in-situ spectroelectrochemistry, a UV-vis spectrophotometer, and a 4-point probe conductometer. The effects of current density, supporting electrolyte type, temperature, and monomer concentrations on the formation of the film were studied. Redox parameters and stability of charged films were obtained by cyclic voltammetry. The most stable copolymer was obtained in lithium perchlorate-acetonitrile …
Chemistry Of Bicyclic Endoperoxides Derived From Dihydropyridine Derivatives: Attempted Synthesis Of Polyhydroxypiperidine Derivatives, Emi̇ne Salamci, Beyhan Bayram, Meti̇n Balci
Chemistry Of Bicyclic Endoperoxides Derived From Dihydropyridine Derivatives: Attempted Synthesis Of Polyhydroxypiperidine Derivatives, Emi̇ne Salamci, Beyhan Bayram, Meti̇n Balci
Turkish Journal of Chemistry
To achieve the synthesis of azasugar derivatives with the utilization of singlet oxygen, pyridine was used as the starting material. The reduction of pyridine followed by a singlet oxygen reaction afforded cyclic aza-endoperoxides (14 and 16). However, many attempts were made to convert the aza-endoperoxides to the corresponding di- and triacetates without success. However, the base-catalyzed rearrangement of 14 gave unprecedented rearrangement products 23 and 24.
Short And Effective Synthesis Of A Thiophene Analogue Of (\Pm)-4-Ipomeanol And Its Biological Evaluation, Jurgen Krauss, Doris Unterreitmeier, Franz Bracher
Short And Effective Synthesis Of A Thiophene Analogue Of (\Pm)-4-Ipomeanol And Its Biological Evaluation, Jurgen Krauss, Doris Unterreitmeier, Franz Bracher
Turkish Journal of Chemistry
The thiophene analogue of (\pm)-4-ipomeanol (1) was prepared in 2 steps starting from 3-iodothiophene and pent-4-yn-2-ol. The key steps were a Sonogashira reaction, followed by HgO catalysed hydratisation of the triple bond. The resulting thiophene was tested in the MTT assay for its cytotoxic activity against HL 60 cells.
Synthesis, Characterization, Crystal Structure And Thermal Behavior Of N'-(4-Chlorobenzoyl)-N,N-Di-N-Butylthiourea And Its Nickel Complex, Hakan Arslan, Ulrich Flörke, Nevzat Külcü, Esra Kayhan
Synthesis, Characterization, Crystal Structure And Thermal Behavior Of N'-(4-Chlorobenzoyl)-N,N-Di-N-Butylthiourea And Its Nickel Complex, Hakan Arslan, Ulrich Flörke, Nevzat Külcü, Esra Kayhan
Turkish Journal of Chemistry
We report the synthesis, structural characterization and thermal behavior of N'-(4-chlorobenzoyl)-N,N-di-n-butylthiourea (HL) and its nickel complex (NiL_2). Some physical properties of the prepared compounds were investigated using elemental analyses, IR, ^1H-NMR, and magnetic susceptibility. The molecular structures of HL and NiL_2 were determined by single crystal X-ray diffraction. HL is a monoclinic, space group P2_1/c with a = 10.7457(5) Å, b = 15.5909(8) Å, c = 10.4536(5) Å, \beta = 104.398(1)°, and V = 1696.34(14) Å^3 with Z = 4 for d_{calc} = 1.280 g/cm^3. NiL_2 is a triclinic, space group P-1 with a = 8.561(3) Å, b = 16.643(6) …
The Synthesis Of 4-Phenoxyphenylglyoxime And 4,4'-Oxybis(Phenylglyoxime) And Their Complexes With Cu(Ii), Ni(Ii) And Co(Ii), Ahmet Coşkun
The Synthesis Of 4-Phenoxyphenylglyoxime And 4,4'-Oxybis(Phenylglyoxime) And Their Complexes With Cu(Ii), Ni(Ii) And Co(Ii), Ahmet Coşkun
Turkish Journal of Chemistry
4-Acetyldiphenyl ether and 4,4'-diacetyldiphenyl ether were synthesized from diphenyl ether and acetyl chloride in the presence of AlCl_3 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, ^1H NMR and ^{13}C NMR spectral data, elemental analysis and magnetic measurements.
Chemical Constituents Of Galium Tortumense, Zühal Güvenalp, Nurcan Kiliç, Cavi̇t Kazaz, Yusuf Kaya, L. Ömür Demi̇rezer
Chemical Constituents Of Galium Tortumense, Zühal Güvenalp, Nurcan Kiliç, Cavi̇t Kazaz, Yusuf Kaya, L. Ömür Demi̇rezer
Turkish Journal of Chemistry
From the aerial parts of Galium tortumense Ehrend & Schönb.-Tem., 8 iridoid glycosides, a flavonol glycoside, a oleanane-type triterpene acid, an ursan-type triterpene acid and a sterol were isolated. The structures of the compounds were elucidated by high field 1D and 2D NMR and EIMS spectroscopies.
Optical Fluoride Sensing With A Bay Region Functionalized Perylenediimide Dye, Funda Yukruk
Optical Fluoride Sensing With A Bay Region Functionalized Perylenediimide Dye, Funda Yukruk
Turkish Journal of Chemistry
A perylenedimiide (PDI) derivative functionalized at the perylene core (bay region) to carry phenyl boronic acid groups was shown to interact with fluoride with changes in the emission and absorption spectrum. These changes are most likely due to fluoride-induced aggregation and/or quenching of the perylenediimide dye. The dye is also selective; among halide ions, fluoride anions generate a significant response. Thus, this class of PDI derivatives is likely to be useful in practical fluoride sensing.
Terpenic And Phenolic Compounds From Sideritis Stricta, F. Pinar Şahi̇n, Nurten Ezer, İhsan Çaliş
Terpenic And Phenolic Compounds From Sideritis Stricta, F. Pinar Şahi̇n, Nurten Ezer, İhsan Çaliş
Turkish Journal of Chemistry
From the overground parts of an endemic Sideritis species, S. stricta, 4 diterpenes, sideridiol (1), isosidol (2), isolinearol (3), and linearol (4); 2 flavonoid glycosides, isoscutellarein 7-O-[6'''-O-acetyl-\beta -D-allopyranosyl-(1 \to 2)]-\beta -D-glucopyranoside (5), and isoscutellarein 7-O-[6'''-O-acetyl-\beta -D-allopyranosyl-(1 \to 2)]-6''-O-acetyl-\beta -D-glucopyranoside (6); a methoxyflavone, xanthomicrol (7); and a phenylethanoid glycoside, verbascoside (=acteoside) (8) were isolated. The structures of the isolated compounds were established based on spectroscopic evidence (UV, IR, 1D- and 2D-NMR, MS).
Iridoids, Flavonoids And Monoterpene Glycosides From Galium Verum Subsp. Verum, L. Ömür Demi̇rezer, Fi̇li̇z Gürbüz, Zühal Güvenalp, Karsten Ströch, Axel Zeeck
Iridoids, Flavonoids And Monoterpene Glycosides From Galium Verum Subsp. Verum, L. Ömür Demi̇rezer, Fi̇li̇z Gürbüz, Zühal Güvenalp, Karsten Ströch, Axel Zeeck
Turkish Journal of Chemistry
From the aerial parts of Galium verum subsp. verum L. were isolated 7 iridoid glycosides, asperuloside (1), asperulosidic acid (2), deacetyl-asperulosidic acid (3), monotropein (4), 6-O-epi-acetylscandoside (5), daphylloside (6) and deacetyl-daphylloside (7); 2 flavonol glycosides, astragalin [= kaempferol 3-O-\beta-glucopyranoside] (8) and rutin [= quercetin 3-O- rutinoside] (9); and 2 monoterpene glycosides, betulalbuside A (10) and (2E)-2,6-dimethyl-2,7-octadien-1,6-diol-6-O-\beta -glucopyranoside (11). The structures of the isolates were established by 1D and 2D NMR spectroscopy in combination with IR, UV and ESI-MS analysis.
Performance Comparison Between Monolithic C18 And Conventional C18 Particle-Packed Columns In The Liquid Chromatographic Determination Of Propranolol Hcl, Sami El Deeb, Hermann Watzig
Performance Comparison Between Monolithic C18 And Conventional C18 Particle-Packed Columns In The Liquid Chromatographic Determination Of Propranolol Hcl, Sami El Deeb, Hermann Watzig
Turkish Journal of Chemistry
Monolithic and conventional particle-packed columns were applied for the determination of propranolol hydrochloride in the presence of its 2 main degradation products, 3-(1-naphthyloxy)-propane-1,2- diol and 4-isopropyl-1,7-bis-(1-naphthyloxy)-4-azaheptane-2,6-diol. The separations were investigated on monolithic columns at flow rates from 1 to 9 mL/min. Fast and efficient separation was obtained by monolithic columns. The analysis time was decreased by about 5-fold on monolithic columns at a flow rate of 4 mL/min, while maintaining sufficient resolution between propranolol and its degradation products. The method was validated using a set of 3 monolithic columns and compared to a conventional (Superspher) C18 column. The precision for …
Synthesis, Crystal Structure And Antifungal/Antibacterial Activity Of Some Novel Highly Functionalized Benzoylaminocarbothioyl Pyrrolidines, H. Ali̇ Döndaş, Yahya Nural, Ni̇zami̇ Duran, Colin Kilner
Synthesis, Crystal Structure And Antifungal/Antibacterial Activity Of Some Novel Highly Functionalized Benzoylaminocarbothioyl Pyrrolidines, H. Ali̇ Döndaş, Yahya Nural, Ni̇zami̇ Duran, Colin Kilner
Turkish Journal of Chemistry
A series of novel highly functionalized benzoylaminocarbothioyl pyrrolidines were prepared from benzoylisothiocyanate and substituted pyrrolidines in excellent yield. The crystal structure of the novel 1-benzoylaminocarbothioyl-5-(naphthyl)- pyrrolidine-2,3,4-tricarboxylicacid trimethyl ester (3a) was determined by X-ray crystal structure analysis. The synthesized compounds were characterized and screened for their in vitro antibacterial and antifungal activities and toxicity. The prepared compounds were tested against the standard strains: Escherichia coli (ATCC 25922), Enterobacter cloacae (ATCC 13047), Enterococcus faecalis (ATCC 29212), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 29213) and Staphylococcus epidermidis (ATCC 12228) and the yeasts Candida albicans (ATCC 90028), Candida krusei (ATCC 6258), Candida parapsilosis …
Superabsorbency, Ph-Sensitivity And Swelling Kinetics Of Partially Hydrolyzed Chitosan-G-Poly(Acrylamide) Hydrogels, Ali Pourjavadi, Gholam Reza Mahdavinia
Superabsorbency, Ph-Sensitivity And Swelling Kinetics Of Partially Hydrolyzed Chitosan-G-Poly(Acrylamide) Hydrogels, Ali Pourjavadi, Gholam Reza Mahdavinia
Turkish Journal of Chemistry
Acrylamide (AAm) monomer was directly grafted onto chitosan using ammonium persulfate (APS) as an initiator and methylenebisacrylamide (MBA) as a crosslinking agent under an inert atmosphere. Two factors affecting the swelling capacity of the obtained hydrogel, AAm and MBA concentrations, were studied. The polymer structures were characterized by FTIR spectroscopy. Water absorbencies of the hydrogels were compared between before and after the alkaline hydrolysis treatment. Saponification of chitosan-g-poly(acrylamide) (chitosan-g-PAAm) with a hot sodium hydroxide solution gave rise to a high water absorbency. Swelling of the hydrogel samples in saline solution (0.15 mol/L NaCl, CaCl_2 and AlCl_3) was examined. Swelling capacity …
Synthesis And Vibrational Spectroscopic Study Of Some Metal(Ii) Halide And Tetracyanonickelate Complexes Of Isonicotinic Acid, Ahmet Ataç, Fehmi̇ Bardak
Synthesis And Vibrational Spectroscopic Study Of Some Metal(Ii) Halide And Tetracyanonickelate Complexes Of Isonicotinic Acid, Ahmet Ataç, Fehmi̇ Bardak
Turkish Journal of Chemistry
The M(IN)_2Ni(CN)_4 [where M: Cu, Mn, Zn, IN: Isonicotinic acid, abbreviated to M-Ni-IN] tetracyanonickelate and some metal halide complexes with the following stoichiometries: Cu(IN)X_2 (X:Br,I), Cd(IN)_2X_2, (X:Cl,Br), and Zn(IN)_4X_2 (X:Br,I) were synthesized for the first time. Their FT-IR spectra were reported in the 4000-400 cm^{-1} region. Vibrational assignments were given for all the observed bands. The analysis of the vibrational spectra indicates that there are some structure-spectrum correlations. For a given series of isomorphous complexes, the sum of the difference between the values of the vibrational modes of uncoordinated isonicotinic acid that were coordinated to the metal ion isonicotinic acid …
Synthesis Of Some New Functionalized Octasilsesquioxane Hybrid Nanoclusters. Iii. Potential Of The Octameric Clusters As Hydraulic Lubricating Fluids, Enock O. Dare
Turkish Journal of Chemistry
The reaction of suitable organic compounds such as \omega -halo-1-alkenes, allyltrichlorosilane or 2-methyl-3-butyn-2-ol in combination with a well-defined inorganic silsesquioxane, H_8Si_8O_{12} A cores, leads to covalently bound organic-inorganic hybrid materials in high yields. The hydraulic fluid properties of these viscous hybrid materials were evaluated and compared with those of some commercially available hydraulic fluids: Mobil EAL 224H, Super-V (AP) and Puroil SHO. The results showed that most silsesquioxane semi-liquids possess hydraulic fluid properties comparable to those of the 3 commercial lubricants.
A New Flame-Retardant Polyamide Containing Phosphine Oxide And N,N-(4,4-Diphenylether) Moieties In The Main Chain: Synthesis And Characterization, Khalil Faghihi
Turkish Journal of Chemistry
A new flame-retardant polyamide containing phosphine oxide moieties in the main chain was synthesized from the solution polycondensation reaction of bis(3-aminophenyl) phenyl phosphine oxide with N,N-(4,4-diphenylether) bis trimellitimide, using thionyl chloride, N-methyl-2-pyrolidone, and pyridine as condensing agents. This new polymer was obtained in high yield (92%), has high inherent viscosity (0.73 dL/g), and was characterized by elemental analysis, FT-IR spectroscopy, thermal gravimetric analysis (TGA and DTG), and solubility testing. Furthermore, another polyamide was prepared by the solution polycondensation reaction of N,N-(4,4-diphenylether) bis trimellitimide with 1,4-phenylene diamine, and its flame-retardant behavior was compared to that of the previous one.
Attempted Synthesis Of 1-Cyclohepta-1,2-Dien-1-Ylbenzene And Wurtz-Like Condensation Products In The Reaction Of 1-(2,3-Dibromocyclohept-1-En-1-Yl)Benzene With Zinc, Mustafa Ceylan, Yakup Budak, M. Burcu Gürdere
Attempted Synthesis Of 1-Cyclohepta-1,2-Dien-1-Ylbenzene And Wurtz-Like Condensation Products In The Reaction Of 1-(2,3-Dibromocyclohept-1-En-1-Yl)Benzene With Zinc, Mustafa Ceylan, Yakup Budak, M. Burcu Gürdere
Turkish Journal of Chemistry
7,7-Dibromo-1-phenylbicyclo[4.1.0]heptane 4 was synthesized and its thermal and silver ion-catalyzed rearrangements were studied. Alcohol 8 was converted to 1-(2,3-dibromocyclohept-1-en-1-yl)benzene 6. The zinc-mediated elimination of 1-(2,3-dibromocyclohept-1-en-1-yl)benzene 6 resulted in the formation of 2 isomeric Wurtz-like condensation products 15 and 16 (whose structural assignments were based on ^1H-and ^{13}C-NMR spectral data) instead of the expected 1-cyclohepta-1,2-dien-1-ylbenzene 14.
The Impact Of Polyacrylamide Molecular Weight On Its Adsorption Behavior At The Gold/Acidic Solution Interface, Dragica B. Chamovska, Toma P. Grchev, Maja V. Cvetkovska
The Impact Of Polyacrylamide Molecular Weight On Its Adsorption Behavior At The Gold/Acidic Solution Interface, Dragica B. Chamovska, Toma P. Grchev, Maja V. Cvetkovska
Turkish Journal of Chemistry
Adsorption isotherms for polyacrylamide (PAA) on polycrystalline gold, from sulfuric acid (potential range 0-2.0 V/she; 293 K), were obtained by means of cyclic voltammetry with simultaneous monitoring of the double-layer capacity. The Frumkin isotherm indicates that relatively strong attractive forces are present (a = 0.8-1.0), and the Gibbs energies range between 43 and 56 kJ mol^{-1}. The coverage (\theta) of the metal surface with polymer molecules depends on the molar concentration of PAA, as well as on its molecular weight, and the size of the statistical polymer coil in the solution (R_G = 7.49 \times 10^{-3} \times M_n^{0.64}/nm). The adsorption …
Simple Synthesis Of \Alpha -Oxime Derivatives Of 2-Ketomethyl Quinolines Under Mild And Heterogeneous Conditions, Javad Safari, Mehdi Adib, Firouzeh Sheibani, Zahra Sadeghi
Simple Synthesis Of \Alpha -Oxime Derivatives Of 2-Ketomethyl Quinolines Under Mild And Heterogeneous Conditions, Javad Safari, Mehdi Adib, Firouzeh Sheibani, Zahra Sadeghi
Turkish Journal of Chemistry
2-Ketomethyl quinolines are converted to their \alpha-oximinoketone derivatives in quantitative yields using sodium nitrite in the presence of silica sulfuric acid as nitrosating agent under mild and heterogeneous conditions.
Synthesis Of 1-Cyclohept-1,2-Dien-1-Yl Benzene From 1-(2-Iodo-, Chlorocyclohept-1-En-1-Yl)Benzene And 1-(2-Iodo-, Chlorocyclohept-2-En-1-Yl)Benzene: Its Trapping With Diphenylisobenzofuran, Mustafa Ceylan, Yakup Budak, Murat Ulukaya, M. Burcu Gürdere, Esra Findik
Synthesis Of 1-Cyclohept-1,2-Dien-1-Yl Benzene From 1-(2-Iodo-, Chlorocyclohept-1-En-1-Yl)Benzene And 1-(2-Iodo-, Chlorocyclohept-2-En-1-Yl)Benzene: Its Trapping With Diphenylisobenzofuran, Mustafa Ceylan, Yakup Budak, Murat Ulukaya, M. Burcu Gürdere, Esra Findik
Turkish Journal of Chemistry
The key compounds vinyl iodides 12a and 13a, for the generation of 1-cyclohept-1,2-dien-1-ylbezene (1), were synthesized from cycloheptanone (5). Bromobenzene was converted to the Grignard reagent, which was condensed with 5. Dehydration of alcohol 6 gave alkene 7. Hydroboration of 7 followed by oxidation with PCC afforded ketone 9, which was converted to hydrazone 10. Treatment of 10 with iodine resulted in the formation of 12a and 13a. The other precursors, 12b and 13b, were synthesized from the reaction of 9 with PCl_5. Reactions of 12a, b and 13a, b with KOtBu in a sealed tube at 185 °C gave …
Hydrothermal And Microwave-Assisted Synthesis Of Boroarsenate, Baso_4, Abdulhadi̇ Baykal, Ayten Evren
Hydrothermal And Microwave-Assisted Synthesis Of Boroarsenate, Baso_4, Abdulhadi̇ Baykal, Ayten Evren
Turkish Journal of Chemistry
BAsO_4 was previously synthesized by solid-state reactions at 800 °C and was characterized by X-ray powder diffraction. Now, we succeeded in preparing BAsO_4 from H_3BO_3 and As_2O_5 using hydrothermal synthesis by heating at 160 °C for 3 days (a single-phase product) and using microwave-assisted synthesis, which takes only 5 min to transform a solid mixture of As_2O_5 and (NH_4)_2B_4O_7.4H_2O into the crystalline titled compound (a single-phase product). The crystallinity of the products is higher than that of the solid-state synthesized product given in the literature. Its X-ray powder diffraction patterns, and both Raman and IR spectra were in good agreement …