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Full-Text Articles in Physical Sciences and Mathematics

High Yielding Oxidative Deprotection Of Silyl And Pyranyl Ethers To Their Corresponding Carbonyl Compounds With Strontium Manganate In The Presence Of Aluminium Chloride In Solution And Under Solvent-Free Conditions, Mostafa Gholizadeh, I. Mohmmadpoor Baltork Jan 2008

High Yielding Oxidative Deprotection Of Silyl And Pyranyl Ethers To Their Corresponding Carbonyl Compounds With Strontium Manganate In The Presence Of Aluminium Chloride In Solution And Under Solvent-Free Conditions, Mostafa Gholizadeh, I. Mohmmadpoor Baltork

Turkish Journal of Chemistry

Strontium manganate (SrMnO_4) in the presence of aluminium chloride (AlCl_3) is an efficient reagent for the high yielding oxidative deprotection of aromatic and aliphatic silyl and pyranyl ethers into their corresponding carbonyl compounds, in solution and under solvent-free conditions.


Preparation Of Palladium Composite Membranes On Pore Structure Modified And Non-Modified Supports By Electroless Plating Procedure, Sali̇ha Kiliçarslan, Osman Muzaffer Afyon, Meltem Doğan Jan 2008

Preparation Of Palladium Composite Membranes On Pore Structure Modified And Non-Modified Supports By Electroless Plating Procedure, Sali̇ha Kiliçarslan, Osman Muzaffer Afyon, Meltem Doğan

Turkish Journal of Chemistry

The effects of pore structure of the support on the plating morphology, thickness, and composition were investigated in an electroless plating procedure. Some of the plating studies were carried out directly on commercially available porous glass supports, while others were performed on modified supports. Two modification steps with alumina were applied on tubular supports. Formation of a 60-\mu m-thick layer on the modified support was detected by SEM analysis after the first 2 plating steps, while layer formation was not observed on the non-modified support. It was shown that the formation of a new layer started on the modified support, …


Examination Of The Electroanalytic Performance Of Carbon Nanotube (Cnt) Modified Carbon Paste Electrodes As Xanthine Biosensor Transducers, Ülkü Anik, Meli̇ha Çubukçu Jan 2008

Examination Of The Electroanalytic Performance Of Carbon Nanotube (Cnt) Modified Carbon Paste Electrodes As Xanthine Biosensor Transducers, Ülkü Anik, Meli̇ha Çubukçu

Turkish Journal of Chemistry

The effect of multi-walled carbon nanotube (MWCNT) and single-wall carbon nanotube (SWCNT) on carbon paste electrode (CPE) electrochemical response was examined by introducing various portions of CNT into the CPE. The optimum electrode structure was determined by comparing the prepared electrodes´ electroanalytical performance towards ferricyanide. Then these optimum compositions were modified with xanthine oxidase (XO) enzyme for obtaining a xanthine biosensor. After the optimization of biosensor working conditions, the developed systems were characterized for xanthine. Linearity was obtained in the concentration range between 1 and 100 \mu M xanthine with an RSD value of 3.35% for MWCNT-CPE, while with SWCNT-CPE …


Potentiometric Determination Of The Stability Constants Of Lanthanide Complexes With Iminodiacetic Acid In Water And Dioxane-Water Mixtures, Sevgi̇ Arzik, Ebru Mavi̇oğlu Ayan, A. Sedat Çelebi̇ Jan 2008

Potentiometric Determination Of The Stability Constants Of Lanthanide Complexes With Iminodiacetic Acid In Water And Dioxane-Water Mixtures, Sevgi̇ Arzik, Ebru Mavi̇oğlu Ayan, A. Sedat Çelebi̇

Turkish Journal of Chemistry

The protonation constants of iminodiacetic acid (H_2 ida) and the stability constants of its complexes with Nd(III), Sm(III), Gd(III), Dy(III), and Er(III) ions at metal/ligand mole ratios of 1:1, 1:2, and 1:3 at 25 °C and 0.1 M ionic strength in aqueous medium and 20%, 45%, and 70% w/w dioxane-water mixtures were determined by the potentiometric method using the BEST computer program. The stability constants of the complexes that formed increased as the dioxane content increased. The stability of all the analogues' complexes, both in aqueous medium and in dioxane-water mixtures, were in the order of Nd(III) < Sm(III) < Gd(III) < Dy(III) < Er(III).


Synthesis And Characterization Of New Tridentate Iminooxime Ligands And Their Co(Iii) Complexes, Hasene Mutlu, Gazi̇ İrez Jan 2008

Synthesis And Characterization Of New Tridentate Iminooxime Ligands And Their Co(Iii) Complexes, Hasene Mutlu, Gazi̇ İrez

Turkish Journal of Chemistry

In this study, (hydroxyimino)(2-phenyl(1,2,3,4-tetrahydroquinazolin- 2-yl))methane (H_2L^1) and (hydroxyimino)(2-(2-thienyl)(1,2,3,4- tetrahydroquinazolin-2-yl))methane (H_2L^2) were synthesized by the condensation of 2-(hydroxyimino)-1-phenylethan-1-one (INAP) and 2-(hydroxyimino)-1-(2-thienyl)ethan-1-one (INAT) with 2-aminobenzylamine (2-ABA). Complexes of these ligands with Co^{3+} were prepared with a metal:ligand ratio of 1:2. The ligands and their complexes were elucidated on the basis of elemental analyses, AAS, FT-IR, ^1H- and ^{13}C-NMR spectra, mass spectra, magnetic susceptibility measurements, and molar conductivity.


Comparison Of Catalytic Activities Of Carbon Supported Pt And Pt-Ru Catalysts For Methanol Oxidation In Neutral And Basic Media By Cyclic Voltammetry, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza Jan 2008

Comparison Of Catalytic Activities Of Carbon Supported Pt And Pt-Ru Catalysts For Methanol Oxidation In Neutral And Basic Media By Cyclic Voltammetry, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza

Turkish Journal of Chemistry

The catalytic activities of an equal amount of 3 different carbon supported catalysts containing 10% Pt, 20% Pt + 10% Ru, and 30% Pt were evaluated in neutral and basic media for methanol oxidation by cyclic voltammetry. The prominent oxidation peak for methanol appeared in the forward anodic sweep at around 1.0 V in neutral medium, while in basic medium it appeared at significantly lower potential close to 0.2 V. The peak current for methanol oxidation was higher on a catalyst containing higher Pt loading. The comparison of polarization behavior of 20% Pt + 10% Ru and 30% Pt catalysts …


Synthesis And Biological Activity Of Allosteric Modulators Of Gaba_B Receptors. Part 4. Synthesis Of Potentially Fluorescent Acridines And Conformationally Restricted N-(Arylpropyl)-1-Arylethylamines, Jabbar Khalafy, Rolf H. Prager, Ni Made Puspawati Jan 2008

Synthesis And Biological Activity Of Allosteric Modulators Of Gaba_B Receptors. Part 4. Synthesis Of Potentially Fluorescent Acridines And Conformationally Restricted N-(Arylpropyl)-1-Arylethylamines, Jabbar Khalafy, Rolf H. Prager, Ni Made Puspawati

Turkish Journal of Chemistry

A series of 8 new derivatives of fendiline was prepared for evaluation as allosteric modulators of GABA_B receptors: 4 based on acridine and 4 with restricted distance between the 2 aryl moieties.


Synthesis And Cloning Of A Small Bacillus Pheromone Gene (Comx_{Ro-B-2}) By Primer-Dimer Formation With Pcr, Devri̇m Demi̇r Dora, Tanil Kocagöz, Fi̇li̇z Öner Jan 2008

Synthesis And Cloning Of A Small Bacillus Pheromone Gene (Comx_{Ro-B-2}) By Primer-Dimer Formation With Pcr, Devri̇m Demi̇r Dora, Tanil Kocagöz, Fi̇li̇z Öner

Turkish Journal of Chemistry

ComX pheromone is the major extracellular signaling peptide stimulating transformation in response to high cell density in Bacillus species. In this study, Bacillus mojavensis ComX_{(RO-B-2)} pheromone gene was cloned to pGEMT-Easy vector based on TA cloning of PCR products. The gene encoding 11 amino acid peptides of Bacillus mojavensis RO-B-2 strain ComX pheromone (GLQIYTNWVPS) was obtained by PCR amplification of 2 primers complementary to each other at their 3' end. This eliminated the need for the original bacterial gene as DNA template for PCR. The amplified PCR products were ligated directly without any modification by T4 DNA ligase into pGEMT-Easy …


Preparation, Characterization, And Potentiometric Titrations Of Some New Di-[3-(3-Alkyl/Aryl-4,5-Dihydro-1h-1,2,4-Triazol-5-One-4-Yl)-Azomethinphenyl] Isophthalate/Terephthalate Derivatives, Haydar Yüksek, Özlem Gürsoy Kol Jan 2008

Preparation, Characterization, And Potentiometric Titrations Of Some New Di-[3-(3-Alkyl/Aryl-4,5-Dihydro-1h-1,2,4-Triazol-5-One-4-Yl)-Azomethinphenyl] Isophthalate/Terephthalate Derivatives, Haydar Yüksek, Özlem Gürsoy Kol

Turkish Journal of Chemistry

3-Alkyl(Aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (2) reacted with di-(3-formylphenyl) isophthalate (3) and di-(3-formylphenyl) terephthalate (6) to afford the corresponding 6 novel di-[3-(3-alkyl/aryl-4,5-dihydro-1H-1,2,4-triazol-5-one-4-yl)- azomethinphenyl] isophthalates (4) and 6 novel di-[3-(3-alkyl/aryl-4,5- dihydro-1H-1,2,4-triazol-5-one-4-yl)-azomethinphenyl] terephthalates (7), respectively. The acetylation reactions of compounds 4 and 7 were investigated, and 5 and 8 type compounds were obtained, respectively. The new compounds synthesized were characterized by using IR, ^1H-NMR, ^{13}C-NMR, and UV spectral data together with elemental analysis. In addition, to investigate the effects of solvents and molecular structure upon acidity, compounds 4 and 7 were titrated potentiometrically with tetrabutylammonium hydroxide in 5 non-aqueous solvents (isopropyl alcohol, tert-butyl alcohol, N,N-dimethylformamide, acetone, …


Microwave-Assisted Synthesis Of 1,4´-Diazaflavone And N-Alkyl Derivative Pigments With Anti-Microbial Activity, Nuran Yayli, Osman Üçüncü, Nuretti̇n Yayli, Emi̇ne Demi̇r, Zi̇hni̇ Demi̇rbağ Jan 2008

Microwave-Assisted Synthesis Of 1,4´-Diazaflavone And N-Alkyl Derivative Pigments With Anti-Microbial Activity, Nuran Yayli, Osman Üçüncü, Nuretti̇n Yayli, Emi̇ne Demi̇r, Zi̇hni̇ Demi̇rbağ

Turkish Journal of Chemistry

1,4'-Diazaflavone pigment (2) was synthesized by a simple environmentally friendly microwave-assisted one-pot method for the cyclization of 2'-amino (E)-4''-aza-chalcone (1) under solventless conditions using K-10 clay. In addition, 10 new N-alkyl (C_{5-12, 14-15}) substituted 1,4' -diazaflavonium bromide pigments (3-12) were prepared from compound 2 or directly from compound 1, with corresponding alkyl halides in acetonitrile under reflux. The anti-microbial activity of compounds 1-12 was tested. The N-alkyl substituted 1,4' -diazaflavonium bromides (3-12) showed good antimicrobial activity against the gram-positive bacteria tested with minimal bactericidal concentration (MBC) values for the reference antibiotic kanamycin. The optimum length of the alkyl chain for …


Zinc Perchlorate Hexahydrate Catalyzed Mono- And Bis-Transesterification Of Malonic Esters, Servet Tural Jan 2008

Zinc Perchlorate Hexahydrate Catalyzed Mono- And Bis-Transesterification Of Malonic Esters, Servet Tural

Turkish Journal of Chemistry

Commercially available zinc perchlorate hexahydrate [Zn(ClO_4)_2.6H_2O] was found to be a highly effective catalyst for the transesterification of malonic esters with alcohols. The treatment of methyl-, ethyl-, or \alpha-substituted malonic esters with primary or secondary alcohols in the presence of a catalytic amount of zinc perchlorate results in good to high yields of the corresponding esters (68%-99%). Mono-transesterification products are also obtained in moderate to good yields (22%-42%). The reaction was also carried out with 2-mono- and di-substituted malonic esters, and in the case of 2-mono- and di-substituted malonic esters, the reaction time is, in some cases, shorter, in which …


Hydrogenation Of Citral Over Ni And Ni-Sn Catalysts, Hi̇lal Aykaç, Selahatti̇n Yilmaz Jan 2008

Hydrogenation Of Citral Over Ni And Ni-Sn Catalysts, Hi̇lal Aykaç, Selahatti̇n Yilmaz

Turkish Journal of Chemistry

Liquid phase citral hydrogenation over zeolite-supported monometallic Ni and bimetallic Ni-Sn catalysts was studied. The zeolite support materials were Na-Y, Na-mordenite, and clinoptilolite. Ni and Sn contents of the monometallic and bimetallic catalysts were 8.1-9.2 wt% and 0.46 wt%, respectively. The type of the zeolite support affected the activity and selectivity of the catalysts differently. The main product of the citral hydrogenation reaction was citronellal, for both monometallic (84.5% yield) and bimetallic (44.5% yield) catalysts. The addition of promoter increased the selectivity to unsaturated alcohols (geraniol+nerol), i.e. it changed from 0.9% to 6.3% over mordenite and from 0.9% to 2.1% …


Studies On The Preparation Of \Alpha,\Omega -Telechelic Polymers By The Combination Of Reverse Atom Transfer Radical Polymerization And Atom Transfer Radical Coupling Processes, Bi̇nnur Aydoğan, Yusuf Yağci Jan 2007

Studies On The Preparation Of \Alpha,\Omega -Telechelic Polymers By The Combination Of Reverse Atom Transfer Radical Polymerization And Atom Transfer Radical Coupling Processes, Bi̇nnur Aydoğan, Yusuf Yağci

Turkish Journal of Chemistry

Monofunctional polystyrenes with cyano, carboxylic acid, and hydroxyl terminal groups were synthesized by reverse atom transfer radical polymerization (RATRP) using corresponding azo initiators in conjunction with copper and iron complexes. These functional polymers were further used in the atom transfer radical coupling (ATRC) reaction in the presence of Cu(I) and Cu(0) in order to obtain telechelic polystyrenes. In the iron-mediated system, while RATRP experiments gave satisfactory results, the corresponding ATRC process yielded polymers with low functionality. The copper-mediated system, however, gave contrary results. In the RATRP step, initiation efficiency was rather low and polymers with relatively higher polydispersity were obtained. …


Plasma-Initiated Polymerization Of (2-Methacryloyloxyethyl) Thrimethyl Ammonium Chloride, Yangang He, Gang Li, Jing Miao, Xueqing Yu, Fang Yang, Yingjun Cui, Fengxia Ren, Yang Chao Jan 2007

Plasma-Initiated Polymerization Of (2-Methacryloyloxyethyl) Thrimethyl Ammonium Chloride, Yangang He, Gang Li, Jing Miao, Xueqing Yu, Fang Yang, Yingjun Cui, Fengxia Ren, Yang Chao

Turkish Journal of Chemistry

Plasma-initiated polymerization of (2-methacryloyloxyethyl) thrimethyl ammonium chloride (MTAC)) was studied. The effects of discharge time and discharge power on temperature in a tubular-type reactor chamber were accurately tested by on-line thermocouple, and the equation relating discharge time, discharge power and temperature in the tubular-type reactor chamber was derived. The results indicated that temperature played a very important role in controlling the solubility of Poly(MTAC) in water. For T \ge 130°, Poly(MTAC) was cross-linked, and the highest rate of absorbing water of Poly(MTAC) was 15 g · g^{-1}. For T < 130°, Poly(MTAC) was linear, and the highest intrinsic viscosity of Poly(MTAC) was 420.2 cm^3 · g^{-1}. The polymerization condition of linear Poly(MTAC) was optimized as follows: discharge time 60 s and discharge power 60 W.


Electrochemical Characteristics Of A 7-Ferrocenyl(Carbonyloxy)-1- Heptanethiol-Modified Gold Electrode, Mohammed Muzibur Rahman, Il Cheol Jeon Jan 2007

Electrochemical Characteristics Of A 7-Ferrocenyl(Carbonyloxy)-1- Heptanethiol-Modified Gold Electrode, Mohammed Muzibur Rahman, Il Cheol Jeon

Turkish Journal of Chemistry

The electrochemical properties of 7-ferrocenyl(carbonyloxy)-1-heptanethiol [FcCO_2(CH_2)_7SH] were characterized by an electrochemical quartz crystal microbalance (EQCM). A gold surface was modified with FcCO_2(CH_2)_7SH by the self-assembly method. EQCM was used to investigate mass change during the redox reactions of FcCO_2(CH_2)_7SH monolayers on a modified gold electrode in solution containing K_3Fe(CN)_6 redox species. The FcCO_2(CH_2)_7SH monolayer on gold acts as a mediator for the electron transfer between a gold electrode and electroactive species Fe(CN)_6^{3-/4-} in solution. In both cases, electrochemical current responses were complicated because the observed currents were due to the redox of both the ferrocenyl group immobilized on gold and …


Electron Affinities, Solvation Energies And Redox Potentials Of Some Chalcones: Substituents` Effect And Correlation With Semi-Empirical Mo Energies, Abdur Rahman, Rumana Qureshi, Mehvish Kiran, Farzana Latif Ansari Jan 2007

Electron Affinities, Solvation Energies And Redox Potentials Of Some Chalcones: Substituents` Effect And Correlation With Semi-Empirical Mo Energies, Abdur Rahman, Rumana Qureshi, Mehvish Kiran, Farzana Latif Ansari

Turkish Journal of Chemistry

Experimental and theoretical investigations were carried out on 2 sets of chalcones. Set 1 has an OH group on ring A and Set 2 does not, and both have different substituents on ring B at different positions. The experimental investigations comprised cyclic voltammetric (CV) studies to determine the reactivity in terms of redox potentials in DMF at room temperature (23 \pm 1 °C). Electrochemical parameters from cyclic voltammograms were used to evaluate the reversibility of electron transfer, standard reduction potentials, solvation energies, electron affinities, diffusion coefficients, critical scan rates and heterogeneous electron transfer rate constants. Heterogeneous electron transfer rate constants …


A New And Convenient Method Of Generating Alkyl Isocyanates From Alcohols, Thiols, And Trimethylsilyl Ethers Using A 2,4,6-Trichloro[1,3,5] Triazine/N-Bu_4nocn, Batool Akhlaghinia, Sima Samiei Jan 2007

A New And Convenient Method Of Generating Alkyl Isocyanates From Alcohols, Thiols, And Trimethylsilyl Ethers Using A 2,4,6-Trichloro[1,3,5] Triazine/N-Bu_4nocn, Batool Akhlaghinia, Sima Samiei

Turkish Journal of Chemistry

Alkyl isocyanates are prepared in good to excellent yields by treatment of alcohols, thiols, and trimethylsilyl ethers with 2,4,6-trichloro[1,3,5] triazine/n-Bu_4NOCN in acetonitrile. This method is highly selective for conversion of 1° alcohols to alkyl isocyanates in the presence of 2° and 3° alcohols, thiols, and trimethylsilyl ethers.


Synthesis And Spectral Characterisation Of Chloro Organotin(Iv) Di[3(2`-Hydroxyphenyl)-5-(4-Substituted Phenyl) Pyrazolinates], Umesh Nath Tripathi, Mohammad Safi Ahmad, Goriparthi Venubabu Jan 2007

Synthesis And Spectral Characterisation Of Chloro Organotin(Iv) Di[3(2`-Hydroxyphenyl)-5-(4-Substituted Phenyl) Pyrazolinates], Umesh Nath Tripathi, Mohammad Safi Ahmad, Goriparthi Venubabu

Turkish Journal of Chemistry

Chloro organotin(IV) dipyrazolinates of the type RSnCl(C_{15}H_{12}N_2OX)_2 [where C_{15}H_{12}N_2OX = 3(2'-Hydroxyphenyl)-5(4-X-phenyl)pyrazoline {where X = H (a); CH_3 (b); OCH_3 (c); Cl (d) and R = Me, Pr^n and Ph] were synthesised by the reaction of RSnCl_3 with sodium salt of pyrazolines in 1:2 molar ratio, in anhydrous benzene. These newly synthesised derivatives were characterised by elemental analysis (C, H, N, Cl and Sn), molecular weight measurement and spectral [IR and multinuclear NMR (^1H, ^{13}C and ^{119}Sn)] studies. The bidentate behaviour of the pyrazoline ligands was confirmed by IR, ^1H and ^{13}C NMR spectral data. An octahedral structure around the tin(IV) …


Synthesis And Characterization Of Oligo-2-[(2-Hydroxymethylphenylimino) Methyl] Phenol And Oligo-2-[(2-Hydroxymethylphenylimino) Methyl]-5-Bromo-Phenol, İsmet Kaya, Ayşe Erçağ, Süleyman Çulhaoğlu Jan 2007

Synthesis And Characterization Of Oligo-2-[(2-Hydroxymethylphenylimino) Methyl] Phenol And Oligo-2-[(2-Hydroxymethylphenylimino) Methyl]-5-Bromo-Phenol, İsmet Kaya, Ayşe Erçağ, Süleyman Çulhaoğlu

Turkish Journal of Chemistry

Oligo-2-[(2-hydroxymethylphenylimino) methyl] phenol O-(2-HMPIMP) and oligo-2-[(2-hydroxymet\-hylphenyl imino) methyl]-5-bromo-phenol O-(2-HMPIMBP) were synthesized by the oxidative polycondensation reaction using air as an oxidant in an aqueous alkaline medium at 70 °C. They were characterized by ^1H-NMR, FT-IR, UV-vis, TG, size exclusion chromatography (SEC) and elemental analysis. According to the SEC analyses, the number-average molecular weight (M_n), weight-average molecular weight (M_w) and polydispersity index (PDI) values of O-2-HMPIMBP and O-2-HMPIMP are 1100, 1600 g mol^{-1} and 1.45; and 6000, 6250 g mol^{-1} and 1.04, respectively. According to TG analyses, the weight losses of O-2-HMPIMP and O-2-HMPIMBP are 98.31% and 96.91%, respectively, at 900 …


New Aromatic Polyamide With Azo And Phosphine Oxide Groups In The Main Chain, Khalil Faghihi, Mohsen Hagibeygi Jan 2007

New Aromatic Polyamide With Azo And Phosphine Oxide Groups In The Main Chain, Khalil Faghihi, Mohsen Hagibeygi

Turkish Journal of Chemistry

A new flame-retardant polyamide containing phosphine oxide and azobenzene moieties in the main chain was synthesized by the solution polycondensation reaction of 4,4`-azodibenzoic acid with bis(3-aminophenyl) phenyl phosphine oxide using thionyl chloride, N-methyl-2-pyrrolidone and pyridine. This new polymer was obtained in high yield (96%) and showed high inherent viscosity (0.55 dL/g) and was characterized by elemental analysis, FT-IR spectroscopy, thermal gravimetric analysis (TGA and DTG) and solubility test. Furthermore, another polyamide was prepared by solution polycondensation reaction of 4,4`-azodibenzoic acid with 1,4-phenylene diamine and its flame-retardant behavior was compared by the use of the LOI with the previous one.


Preparation And Characterization Of An Atenolol Selective Electrode Based On A Pvc Matrix Membrane, Nabil S. Nassory, Shabaz A. Maki, Mutaz A. Ali Jan 2007

Preparation And Characterization Of An Atenolol Selective Electrode Based On A Pvc Matrix Membrane, Nabil S. Nassory, Shabaz A. Maki, Mutaz A. Ali

Turkish Journal of Chemistry

Atenolol selective electrodes were prepared based on a complex atenolol-phosphotungstate as an active material using the plasticizers di-butyl phosphate (DBP), tri-butyl phosphate (TBP), o-nitro phenyl octyl ether (NPOE) and di-octyl phthalate (DOPH) in a PVC matrix membrane. The properties of the prepared electrodes were studied, namely slope, concentration range, detection limit, lifetime, pH effect and selectivity. The experimental results showed that the best electrode was based on DOPH as plasticizer, displaying a linear range from 1.00 x 10^{-4} M to 5.00 x 10^{-2} M with a Nernstian slope of 55.91 mV/decade and correlation coefficient of 0.9995. The detection limit was …


Efficient Method For Tetrahydropyranylation Of Phenols And Alcohols Using 2,4,6-Trichloro[1,3,5]Triazine, Batool Akhlaghinia, Elham Roohi Jan 2007

Efficient Method For Tetrahydropyranylation Of Phenols And Alcohols Using 2,4,6-Trichloro[1,3,5]Triazine, Batool Akhlaghinia, Elham Roohi

Turkish Journal of Chemistry

Alcohols and phenols were tetrahydropyranylated in the presence of 2,4,6-trichloro[1,3,5]triazine in good to excellent yields in acetonitrile.


A Convenient Method For The Preparation Of 2-Aminobenzophenone Derivatives Under Ultrasonic Irradiation, Javad Safaei-Ghomi, Manouchehr Fadaeian, Alireza Hatami Jan 2007

A Convenient Method For The Preparation Of 2-Aminobenzophenone Derivatives Under Ultrasonic Irradiation, Javad Safaei-Ghomi, Manouchehr Fadaeian, Alireza Hatami

Turkish Journal of Chemistry

A quick and convenient method for the preparation of 2-aminobenzophenone derivatives is described. This approach consists of the nucleophilic substitution reaction of nitrobenzenes by phenylacetonitrile under conventional and ultrasonic conditions followed by reduction of the produced 2,1-benzisoxazole to 2-aminobenzophenone. This 2-step reaction was studied by changing the reaction parameters (reaction temperature, ultrasound power, and reaction time). The results clearly demonstrated that using ultrasound irradiation results in a high yield within a short reaction time.


Gold(Iii) Complex Of Caffeine: Synthesis, Isolation And Spectroscopic Characterization, Bojidarka Ivanova Jan 2007

Gold(Iii) Complex Of Caffeine: Synthesis, Isolation And Spectroscopic Characterization, Bojidarka Ivanova

Turkish Journal of Chemistry

Au(III)-caffeine complex was synthesized and characterized by means of solid-state linear-dichroic infrared spectral analysis (IRLD), ^1H-NMR, MS, DSC and TGA methods. The caffeine (I) is monodentate and coordinated with metal ion through its N9 atom at molar ratio metal to ligand 1:1. The other 3 positions in the Au(III) coordination sphere are occupied by Cl^-, thus forming [Au^{3+}(C_8H_{10}N_4O_2)Cl_3] complex. IR-characteristic band assignment in the 4000-400 cm^{-1} IR region of pure ligand and corresponding Au(III)complex was performed.


Examination Of Gold As A Metal Promoter Of Sulphated Zirconia In N-Heptane Isomerisation At Low Temperature, Ümi̇t Bi̇lge Demi̇rci̇, Francois Garin Jan 2007

Examination Of Gold As A Metal Promoter Of Sulphated Zirconia In N-Heptane Isomerisation At Low Temperature, Ümi̇t Bi̇lge Demi̇rci̇, Francois Garin

Turkish Journal of Chemistry

Isomerisation of nC_7 over a sulphated zirconia (SZ)-based bifunctional catalyst was studied at 150 °C. Au, Ir, Pd and Pt were used as promoters of SZ. The first objective was the production of C_7 isomers with high octane numbers. PtSZ is the most suitable catalyst despite low conversions and a high proportion of methylhexanes instead of dimethylpentanes. The second objective was to assess Au as a promoter of SZ. Au shows slight hydrogenation abilities, displaying behaviour similar to that of Pd, but is inactive towards alkane activation. These promising but inadequate results suggested that Au could be used as the …


Chemoenzymatic Synthesis Of 2-Bromo-6-Hydroxy-3-Methoxy-2-Cyclohexen-1-One, Emi̇ne Özgül Karaaslan, Yasemi̇n Toka Jan 2007

Chemoenzymatic Synthesis Of 2-Bromo-6-Hydroxy-3-Methoxy-2-Cyclohexen-1-One, Emi̇ne Özgül Karaaslan, Yasemi̇n Toka

Turkish Journal of Chemistry

A chemoenzymatic synthesis of 2-bromo-6-hydroxy-3-methoxy-2- cyclohexen-1-one starting from cyclohexane-1,3-dione is reported. Manganese(III) acetate-mediated acetoxylation followed by the enzyme-mediated hydrolysis of \alpha'-acetoxy enone affords hydroxy-enone 5 and acetoxy enone 4 with high enantiomeric excesses in good yields.


Iridoid Glucosides From Lamium Garganicum Subsp. Laevigatum, Tayfun Ersöz, Duygu Kaya, Funda Nuray Yalçin, Cavi̇t Kazaz, Erhan Palaska, Charlott H. Gotfredsen, Soren R. Jensen, İhsan Çaliş Jan 2007

Iridoid Glucosides From Lamium Garganicum Subsp. Laevigatum, Tayfun Ersöz, Duygu Kaya, Funda Nuray Yalçin, Cavi̇t Kazaz, Erhan Palaska, Charlott H. Gotfredsen, Soren R. Jensen, İhsan Çaliş

Turkish Journal of Chemistry

Phytochemical investigations on the above-ground parts of Lamium garganicum subsp. laevigatum resulted in the isolation of 7 iridoid glucosides: shanzhiside methyl ester (1), barlerin (8-O-acetylshanzhiside methyl ester) (2), 6-O-syringyl-8-O-acetylshanzhiside methyl ester (3), 6\beta-hydroxyipolamiide (4), lamalbide (5), dehydropenstemoside (6), and sesamoside (7). The structure of the iridoids was elucidated by spectroscopic (UV, IR, 1D- and 2D-NMR, and ESI-MS) evidence.


Synthesis Of Nitrogen-Containing Heterocycles From The Reaction Of Amidrazones With \Alpha-Haloesters, Hany M. Dalloul, Peter H. Boyle Jan 2007

Synthesis Of Nitrogen-Containing Heterocycles From The Reaction Of Amidrazones With \Alpha-Haloesters, Hany M. Dalloul, Peter H. Boyle

Turkish Journal of Chemistry

The reaction of amidrazones 1 with \alpha-haloesters 2 formed 1,3,5-substituted 4,5-dihydro-1,2,4-triazin-6-ones (4a-z) rather than 1,2,4-triazin-5-one derivatives (5a-z). The microanalysis and spectral data of the synthesized compounds are in full agreement with their molecular structure.


Basic Al_2o_3 As A Recyclable Reagent For The Protection Of Carbonyl Groups With Phenylhydrazine Derivatives And Semicarbazides, Khodabakhsh Niknam, Ali Reza Kiasat, Bahador Karami, Nima Heydari Jan 2007

Basic Al_2o_3 As A Recyclable Reagent For The Protection Of Carbonyl Groups With Phenylhydrazine Derivatives And Semicarbazides, Khodabakhsh Niknam, Ali Reza Kiasat, Bahador Karami, Nima Heydari

Turkish Journal of Chemistry

Basic alumina is employed as an inorganic basic solid catalyst for the clean and less hazardous protection of carbonyl compounds, such as phenylhydrazones, 2,4-dinitrophenylhydrazones, semicarbazones, and thiosemicarbazones, under solvent-free conditions. The reactions proceed smoothly and require a short reaction time with good to excellent yields, and the alumina used can be recycled.


Synthesis And Characterization Of Polyimides Prepared From Optically Active (R,R) And (S,S)-1,3-Bis(P-N,N´-Dimethylaminobenzyl)-Perhydrobenzimidazol-2-Thion, Murat Yi̇ği̇t, Turgay Seçki̇n, Süleyman Köytepe, Engi̇n Çeti̇nkaya Jan 2007

Synthesis And Characterization Of Polyimides Prepared From Optically Active (R,R) And (S,S)-1,3-Bis(P-N,N´-Dimethylaminobenzyl)-Perhydrobenzimidazol-2-Thion, Murat Yi̇ği̇t, Turgay Seçki̇n, Süleyman Köytepe, Engi̇n Çeti̇nkaya

Turkish Journal of Chemistry

This paper presents the synthesis and characterization of polyimides containing a chiral (R,R) or (S,S) 1,3-bis(p-N,N´-dimethylaminobenzyl)-perhydrobenzimidazol-2-thion unit in the backbone. The reactions occur between equimolar amounts of a dianhydride and an aromatic dimethylamine in the presence of the solvent N-methyl-2-pyrollidone (NMP). In this work, the chiral monomer RR and SS -1,3-bis(p-N,N´-dimethylaminobenzyl)-perhydrobenzimidazol- 2-thion were used as diamines. The polyimides obtained were characterized by thermogravimetry (TGA), differential thermal analysis (DTA), differential scanning calorimeter (DSC), infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). It was found that the composition of the polymer had a significant effect upon the thermal behavior of the material.