Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1141 - 1170 of 2628

Full-Text Articles in Physical Sciences and Mathematics

A New Series Of Cu(Ii) And Ni(Ii) Complexes Of No Bidentate 4-No$_{2}$-Benzoylhydrazones: Synthesis, Characterization, And Biological Studies, Hati̇ce Başpinar Küçük, Emel Mataraci Kara, Berna Özbek Çeli̇k Jan 2015

A New Series Of Cu(Ii) And Ni(Ii) Complexes Of No Bidentate 4-No$_{2}$-Benzoylhydrazones: Synthesis, Characterization, And Biological Studies, Hati̇ce Başpinar Küçük, Emel Mataraci Kara, Berna Özbek Çeli̇k

Turkish Journal of Chemistry

A series of new nickel(II) and copper(II) hydrazone complexes \textbf{1--14}, containing a bidentate NO-donor hydrazone ligand, derived from 4-nitrobenzoylhydrazide and several aliphatic and aromatic aldehydes were synthesized, and their chemical structures were confirmed by means of FT-IR, UV-Vis, $^{1}$H and $^{13}$C NMR, mass spectral data, conductance measurements, and elemental analyses. The spectral data of the newly synthesized complexes show the formation of a 1:2 [metal:ligand] ratio. The ligands and their complexes were also investigated for their possible in vitro antimicrobial activities against \textit{S. aureus}, \textit{S. epidermidis}, \textit{E. coli}, \textit{K. pneumonia}, \textit{P. aeruginosa}, \textit{P. mirabilis}, \textit{E. faecalis}, and \textit{C. albicans}. Among …


Synthesis Of Novel 1,2,4-Triazoles And Triazolo-Thiadiazines As Anticancer Agents, Thoraya Abd El-Reheem Farghaly, Magda Ahmad Abdallah, Huda Kamel Mmahmoud Jan 2015

Synthesis Of Novel 1,2,4-Triazoles And Triazolo-Thiadiazines As Anticancer Agents, Thoraya Abd El-Reheem Farghaly, Magda Ahmad Abdallah, Huda Kamel Mmahmoud

Turkish Journal of Chemistry

A new series of 7-arylazo-5$H$-3-(trifluoromethyl)-6-methyl-1,2,4-triazolo-[3,4-$b$]-1,3,4-thiadiazines was prepared by reaction of 4-amino-3-trifluoromethyl-5-mercapto-1,2,4-triazoles with $N$-aryl-2-oxo-propane hydrazonoyl chloride in dioxane under reflux in the presence of triethylamine. Furthermore, Schiff bases of 4-amino-5-mercapto-1,2,4-triazole derivatives were reacted with a variety of hydrazonoyl chlorides and gave the respective hydrazonothioates. In addition, the novel \textit{bis}-(1,2,4-triazole-3-thione) was reacted with the appropriate hydrazonoyl chloride in dioxane under reflux in the presence of triethylamine to give the corresponding \textit{bis}-(1,2,4-triazolethiohydrazonoate). The structures of the new compounds were established based on elemental and spectral data. The mechanism of the studied reaction was also discussed. Moreover, some of the new products were screened …


Thermogravimetric Analysis-Based Screening Of Metal (Ii) Chlorides As Dopants For The Destabilization Of Solid-State Hydrazine Borane, Weiguang Chen, Umit Bilge Demirci Jan 2015

Thermogravimetric Analysis-Based Screening Of Metal (Ii) Chlorides As Dopants For The Destabilization Of Solid-State Hydrazine Borane, Weiguang Chen, Umit Bilge Demirci

Turkish Journal of Chemistry

Thermogravimetric analysis (TGA) is a powerful technique for screening boranes envisaged for chemical hydrogen storage. The demonstration is based on the use of six metal (II) chlorides (MCl$_{2})$ (with M as 3d-metal or d$^{8}$-metal) as destabilizing agents of solid-state hydrazine borane (N$_{2}$H$_{4}$BH$_{3})$. On the basis of TGA profiles combined with derivative thermogravimetric (DTG) curves, it is shown that: e.g. (1) CuCl$_{2}$ is an inefficient dopant whereas it is efficient towards ammonia borane (NH$_{3}$BH$_{3})$; (2) one of the best destabilization results is achieved with N$_{2}$H$_{4}$BH$_{3}$ doped by 10 wt{\%} CuCl$_{2}$-NiCl$_{2}$, the sample decomposing from 30 $^{\circ}$C with greatly mitigated amounts of …


Effective Recognition Of Multiple Anions By An Azobenzene--Al$^{\Mathbf{3+}}$ System, Ye Zhang, Ping Jia, Zhangfa Tong, Hai-Bo Liu, Jing Wang Jan 2015

Effective Recognition Of Multiple Anions By An Azobenzene--Al$^{\Mathbf{3+}}$ System, Ye Zhang, Ping Jia, Zhangfa Tong, Hai-Bo Liu, Jing Wang

Turkish Journal of Chemistry

A ready-to-use multifunctional coordinative system, 2,2'-dihydroxyazobenzene --aluminum (III) (DHAB--Al$^{3+})$, was created to recognize several anions effectively through three channels, namely colorimetric detection, UV-Vis spectroscopy, and fluorescence spectroscopy. Under naked eye visualization, the H$_{2}$PO$_{4}^{-}$ can be readily distinguished from the other anions by the DHAB--Al$^{3+}$ system through a change in color from reddish-orange to light yellow. H$_{2}$PO$_{4}^{-}$ was qualitatively detected by using UV-Vis and fluorescence spectra. Differentiating SO$_{3}^{2-}$, HPO$_{4}^{2-}$, and HCO$_{3}^{-}$ anions colorimetrically is difficult; thus, CO$_{3}^{2-}$, SO$_{3}^{2-}$, HPO$_{4}^{2-}$, and HCO$_{3}^{-}$ were discriminated by adopting distinct changes in the UV-Vis spectra. CO$_{3}^{2-}$, HPO$_{4}^{2-}$, and HCO$_{3}^{-}$ were accurately quantified using fluorescence spectra. …


Preparation And Physicochemical Characterizations Of Solid Lipid Nanoparticles Containing Dotap$^®$ For Dna Delivery, Gülay Büyükköroğlu, Emi̇ne Yasemi̇n Yazan, Ayşe Fi̇li̇z Öner Jan 2015

Preparation And Physicochemical Characterizations Of Solid Lipid Nanoparticles Containing Dotap$^®$ For Dna Delivery, Gülay Büyükköroğlu, Emi̇ne Yasemi̇n Yazan, Ayşe Fi̇li̇z Öner

Turkish Journal of Chemistry

The aim of this study was to prepare and evaluate stable cationic solid lipid nanoparticles (SLNs) as colloidal carriers for gene therapy. SLNs were mainly composed of three different biocompatible and biodegradable matrix lipids called tripalmitin, glyceryl dibehenate, and triglyceride, all containing the cationic lipid $N$-(1-(2,3-dioleoyloxy)propyl)-$N,N,N$-trimethylammonium (DOTAP$^®$). Each of these SLNs were divided into three parts and characterized by applying different processes: Part I was autoclaved (121 $^{\circ}$C, 15 min), Part II was lyophilized (5 mbar, --50 $^{\circ}$C), and Part III was kept in its intact form. These parts were stored at 4 $^{\circ}$C, 25 $^{\circ}$C (room temp.), and 40 …


Separation And Preconcentration Of Lead(Ii), Cobalt(Ii), And Nickel(Ii) On Edta Immobilized Activated Carbon Cloth Prior To Flame Atomic Absorption Spectrometric Determination In Environmental Samples, Zeid Abdullah Alothman, Erkan Yilmaz, Mohamed Habi̇la, Mustafa Soylak Jan 2015

Separation And Preconcentration Of Lead(Ii), Cobalt(Ii), And Nickel(Ii) On Edta Immobilized Activated Carbon Cloth Prior To Flame Atomic Absorption Spectrometric Determination In Environmental Samples, Zeid Abdullah Alothman, Erkan Yilmaz, Mohamed Habi̇la, Mustafa Soylak

Turkish Journal of Chemistry

The synthesis and characterization of ethylenediaminetetraacetic acid immobilized activated carbon cloth was performed in the present work. It was used for preconcentration-separation of lead(II), cobalt(II), and nickel(II) at trace levels as an adsorbent. Factors including pH, concentration and volume of eluent, sample and eluent flow rates, sample volume, and effect of coexisting ions on the solid phase extraction of analytes were examined. The preconcentration factor was 50. The detection limits for Pb(II), Co(II), and Ni(II) were 4.39, 0.99 and 0.91 $\mu $g L$^{-1}$, respectively. The adsorption capacity for Pb(II), Co(II), and Ni(II) ions was found as 11.0, 11.2, and 10.2 …


Properties And Some In Vitro Studies Of 6-Phosphogluconate Dehydrogenase Purified From The Liver Of Chalcalburnus Tarichi, The Only Fish Living In Lake Van's Highly Alkaline Water (Ph 9.8), Muhammet Güler, Vedat Türkoğlu, Mehmet Riza Kivanç Jan 2015

Properties And Some In Vitro Studies Of 6-Phosphogluconate Dehydrogenase Purified From The Liver Of Chalcalburnus Tarichi, The Only Fish Living In Lake Van's Highly Alkaline Water (Ph 9.8), Muhammet Güler, Vedat Türkoğlu, Mehmet Riza Kivanç

Turkish Journal of Chemistry

In this study, some enzymology parameters and some antibiotics affecting the enzyme activity of 6-phosphogluconate dehydrogenase (6PGD) extracted from t the livers of fish from Lake Van (\textit{Chalcalburnus tarichi}) were investigated because it is an important enzyme-producing NADPH, a reductive power, protecting the cell against the oxidative agents by producing reduced glutathione. The crude enzyme solution was obtained by using the affinity chromatography method. The native molecular weight of the enzyme is $\sim $90,000 $\pm $ 3000 Da and it is composed of two subunits with identical molecular weights of $\sim $46,000 Da as exhibited on sodium dodecyl sulfate-polyacrylamide gel …


Spectrophotometric Determination Of Iron Species Using Ionic Liquid Ultrasound Assisted Dispersive Liquid--Liquid Microextraction, Alireza Bazmandegan, Ali Mohammad Haji Shabani, Sayessteh Dadfarnia, Mahboubeh Saeidi, Masoud Rohani Moghadam Jan 2015

Spectrophotometric Determination Of Iron Species Using Ionic Liquid Ultrasound Assisted Dispersive Liquid--Liquid Microextraction, Alireza Bazmandegan, Ali Mohammad Haji Shabani, Sayessteh Dadfarnia, Mahboubeh Saeidi, Masoud Rohani Moghadam

Turkish Journal of Chemistry

A simple and efficient method for speciation and determination of iron in different water samples was developed. The method is based on ionic liquid ultrasound assisted dispersive liquid--liquid microextraction (IL-USA-DLLME) followed by spectrophotometric determination. Fe(II) is complexed with 2,4,6-tri(2'-pyridyl)-l,3,5-triazine (TPTZ{)}, neutralized through ion pair formation with sodium dodecyl sulfate (SDS) and extracted into 1-hexyl-3-methylimidazolium hexafluorophosphate [C$_{6}$MIM][PF$_{6}$]. Total iron amount was determined after reduction of Fe(III) to Fe(II) with hydroxylamine hydrochloride. The concentration of Fe(III) was determined from the difference of concentration of total iron and Fe(II). The important parameters such as the type and volume of the extraction solvent, pH, …


Green And Efficient Synthesis Of Novel Bispyrazoles Through A Tandem Knoevenagel And Michael Type Reaction Using Nanowire Zinc Oxide As A Powerful And Recyclable Catalyst, Khalil Eskandari, Bahador Karami, Saeed Khodabakhshi, Seyyed Jafar Hoseini Jan 2015

Green And Efficient Synthesis Of Novel Bispyrazoles Through A Tandem Knoevenagel And Michael Type Reaction Using Nanowire Zinc Oxide As A Powerful And Recyclable Catalyst, Khalil Eskandari, Bahador Karami, Saeed Khodabakhshi, Seyyed Jafar Hoseini

Turkish Journal of Chemistry

Zinc oxide nanowires (ZnO NWs) were prepared and characterized by scanning electron microscopy, powder X-ray diffraction, and transmission electron microscopy analyses. ZnO NWs were then employed as heterogeneous and recyclable catalyst for green synthesis of some new and known bispyrazole derivatives through a tandem Knoevenagel and Michael type addition reaction of aromatic aldehyde and pyrazolone. The synthetic method is operationally simple and affords product with high yields in short reaction times.


Enzyme-Assisted Modification Of Cellulose/Chitin Fibers With Nipaam, Anamaria Irimia, Emilia Csiszar, Marius Dobromir, Florica Doroftei, Cornelia Vasile Jan 2015

Enzyme-Assisted Modification Of Cellulose/Chitin Fibers With Nipaam, Anamaria Irimia, Emilia Csiszar, Marius Dobromir, Florica Doroftei, Cornelia Vasile

Turkish Journal of Chemistry

Coating processes are applied in order to improve coating adhesion and resistance to degradation. Covalently bound organic coatings rather than merely physically bound ones assure stable modification. In this study a novel two-step process was developed to modify cellulose/chitin mix fibers consisting of enzymatic activation with a commercial cellulase, followed by a coupling reaction with N-isopropylacrylamide (or poly (N-isopropylacrylamide)) in the presence of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide (EDC) and N-hydroxysuccinimide (NHS). Both enzyme-activated and subsequently modified samples were characterized by ATR-FTIR, XPS, and SEM. All obtained results confirm the structural and morphological changes of the fiber surface after the application of the two-step …


Synthesis And In Vitro Cytotoxic Activity Of Novel Pyrazolo[1,5-$A$]Pyrimidines And Related Schiff Bases, Ashraf Sayed Hassan, Taghrid Shoukry Hafez, Souad Abdel Meguid Osman, Mamdouh Moawad Ali Jan 2015

Synthesis And In Vitro Cytotoxic Activity Of Novel Pyrazolo[1,5-$A$]Pyrimidines And Related Schiff Bases, Ashraf Sayed Hassan, Taghrid Shoukry Hafez, Souad Abdel Meguid Osman, Mamdouh Moawad Ali

Turkish Journal of Chemistry

The reaction of 5-amino-3-(4-methoxyphenylamino)-$N$-aryl-1$H$-pyrazole-4-carboxamides \textbf{1a}--\textbf{c} with ethyl acetoacetate \textbf{2} and 2-(4-fluorobenzylidene)malononitrile \textbf{6} yielded pyrazolo[1,5-$a$]pyrimidines \textbf{5a}--\textbf{c} and \textbf{9a}--\textbf{c}, respectively. On the other hand, Schiff bases \textbf{11a}--\textbf{f} were obtained upon treatment of carboxamides \textbf{1a}--\textbf{c} with some selected aldehydes \textbf{10a }and\textbf{ b}. The newly synthesized compounds were characterized and confirmed by analytical and spectroscopic data (IR, MS, $^{1}$H NMR, and $^{13}$C NMR). Pyrazolo[1,5-$a$]pyrimidines \textbf{5a}--\textbf{c} and \textbf{9a}--\textbf{c} and Schiff bases \textbf{11b}--\textbf{f} were investigated for their cytotoxicity against four human cancer cell lines (colon HCT116, lung A549, breast MCF-7, and liver HepG2) according to SRB assay and the structure--activity relationship was discussed.


Palladium-Catalysed Suzuki--Miyaura Cross-Coupling With Imidazolylidene Ligands Substituted By Crowded Resorcinarenyl And Calixarenyl Units, Neslihan Sahin, David Semeril, Eric Brenner, Dominique Matt, Cemal Kaya, Loic Toupet Jan 2015

Palladium-Catalysed Suzuki--Miyaura Cross-Coupling With Imidazolylidene Ligands Substituted By Crowded Resorcinarenyl And Calixarenyl Units, Neslihan Sahin, David Semeril, Eric Brenner, Dominique Matt, Cemal Kaya, Loic Toupet

Turkish Journal of Chemistry

Two $N$-heterocyclic carbene (NHC) palladium complexes of formula [PdBr$_{2}$(NHC)(pyridine)] in which the carbenic ring is flanked by sterically crowded cavitand substituents were prepared from appropriate imidazolium salts bearing either two resorcinarene or a combination of resorcinarene and calixarene fragments. Both complexes displayed high stability and good activities in the cross-coupling of aryl bromides with phenyl boronic acid. One of the imidazolium salts was characterised by an X-ray diffraction study.


Sonogashira Reactions For The Synthesis Of Polarized Pentacene Derivatives, Stephane Schweizer, Guillaume Erbland, Philippe Bisseret, Jacques Lalevee, Didier Le Nouen, Nicolas Blanchard Jan 2015

Sonogashira Reactions For The Synthesis Of Polarized Pentacene Derivatives, Stephane Schweizer, Guillaume Erbland, Philippe Bisseret, Jacques Lalevee, Didier Le Nouen, Nicolas Blanchard

Turkish Journal of Chemistry

Five dissymmetrically functionalized anthracene analogues (3a-e) were synthesized from commercially available 9,10-dibromoanthracene through an efficient bromine-iodine exchange followed by two successive Sonogashira coupling reactions. The resulting TMS-anthracene analogues are interesting building blocks for the preparation of highly $\pi$-conjugated dissymmetric pentacene-based dyads, which could be used as active semiconducting layers for organic field-effect transistors (OFETs).


A Simple Approach To Bis-Spirocycles And Spiroindole Derivatives Via Green Methods Such As Fischer Indolization, Ring-Closing Metathesis, And Suzuki--Miyaura Cross-Coupling, Sambasivarao Kotha, Rashid Ali Jan 2015

A Simple Approach To Bis-Spirocycles And Spiroindole Derivatives Via Green Methods Such As Fischer Indolization, Ring-Closing Metathesis, And Suzuki--Miyaura Cross-Coupling, Sambasivarao Kotha, Rashid Ali

Turkish Journal of Chemistry

We have developed a simple synthetic methodology for bis-spirocycles and spiroindole derivatives starting with a commercially available 6-bromo-2-tetralone. Here, we have used Fischer indolization, ring-closing metathesis, and Suzuki--Miyaura cross-coupling as key steps to assemble a variety of spirocyclic frameworks. The methodology developed here is simple and it may be useful to prepare various spirocycles containing indole moiety.


Copper-Free Sonogashira Cross-Coupling Reactions Catalyzed By An Efficient Dimeric C,N-Palladacycle In Dmf/H$_{2}$O, Kazem Karami, Nasrin Haghighat Naeini Jan 2015

Copper-Free Sonogashira Cross-Coupling Reactions Catalyzed By An Efficient Dimeric C,N-Palladacycle In Dmf/H$_{2}$O, Kazem Karami, Nasrin Haghighat Naeini

Turkish Journal of Chemistry

Very small concentrations of a dimeric C,N-palladacycle were used as an efficient homogeneous catalyst for Sonogashira cross-coupling reactions between various aryl halides and phenylacetylene. The catalytic reactions were performed without the need for copper in DMF/H$_{2}$O. This catalytic system shows excellent yields for aryl iodides and bromides and even in the case of aryl chlorides.


Palladium-Catalyzed Ligand-Free And Efficient Suzuki--Miyaura Reaction Of $N$-Methyliminodiacetic Acid Boronates In Water, Chun Liu, Xinmin Li, Xinnan Wang, Jieshan Qiu Jan 2015

Palladium-Catalyzed Ligand-Free And Efficient Suzuki--Miyaura Reaction Of $N$-Methyliminodiacetic Acid Boronates In Water, Chun Liu, Xinmin Li, Xinnan Wang, Jieshan Qiu

Turkish Journal of Chemistry

A green and efficient protocol has been developed for the Pd(OAc)$_{2}$-catalyzed ligand-free Suzuki--Miyaura reaction of $N$-methyliminodiacetic acid (MIDA) boronates in water. In the presence of Pd(OAc)$_{2}$ as a catalyst and ($i$-Pr)$_{2}$NH as a base, the cross-coupling reactions of aryl bromides with aryl MIDA boronates proceeded smoothly in water without any surfactant, and various functional groups were tolerated under the optimized conditions.


Reactivity Of The 2-Aryl-6,8-Dibromo-2,3-Dihydroquinolin-4(1$H)$-Ones In A Palladium Catalyzed Sonogashira Cross-Coupling Reaction, Malose Jack Mphahlele, Felix Adetunji Oyeyiola Jan 2015

Reactivity Of The 2-Aryl-6,8-Dibromo-2,3-Dihydroquinolin-4(1$H)$-Ones In A Palladium Catalyzed Sonogashira Cross-Coupling Reaction, Malose Jack Mphahlele, Felix Adetunji Oyeyiola

Turkish Journal of Chemistry

Pd/C-PPh$_{3}$--CuI catalyzed Sonogashira cross-coupling of the 2-aryl-6,8-dibromo-2,3-dihydroquinolin-4(1$H)$-ones with phenyl acetylene or 3-butyn-1-ol afforded the corresponding 8-alkynylated quinolin-4(1$H)$-one derivatives, exclusively. Double carbo-substitution to afford the 6,8-dialkynyl derivatives was observed when PdCl$_{2}$(PPh$_{3})_{2}$ was used as Pd(0) source. The monoalkynylated derivatives were, in turn, subjected to PdCl$_{2}$ in acetonitrile under reflux to afford either the corresponding 2,4-diaryl-8-bromopyrrolo[3,2,1-\textit{ij}]quinolinones or the 8-(4-hydroxybutanoyl)-substituted quinolinone derivatives, exclusively. Suzuki--Miyaura cross-coupling of the 2-aryl-6-bromo-8-(alkynyl)quinolin-4-ones afforded the 2,4,8-trisubstituted pyrrolo[3,2,1-\textit{ij}]quinolin-6-ones.


Efficient C--C Cross-Coupling Reactions By (Isatin)-Schiff Base Functionalized Magnetic Nanoparticle-Supported Cu(Ii) Acetate As A Magnetically Recoverable Catalyst, Seyedeh Simin Miri, Mehdi Khoobi, Fatemeh Ashouri, Farnaz Jafarpour, Parviz Rashidi Ranjbar, Abbas Shafiee Jan 2015

Efficient C--C Cross-Coupling Reactions By (Isatin)-Schiff Base Functionalized Magnetic Nanoparticle-Supported Cu(Ii) Acetate As A Magnetically Recoverable Catalyst, Seyedeh Simin Miri, Mehdi Khoobi, Fatemeh Ashouri, Farnaz Jafarpour, Parviz Rashidi Ranjbar, Abbas Shafiee

Turkish Journal of Chemistry

Copper catalysts were simply fabricated through surface modification of superparamagnetic iron nanoparticles with indoline-2,3-dione(isatin)-Schiff-base and interaction with Cu from low-cost commercially available starting materials. Catalysts were characterized using atomic absorption spectrophotometry, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, vibrating sample magnetometry, UV/Vis spectroscopy, scanning electron microscopy, and transmission electron microscopy. These catalysts showed high efficiency for phosphine-free Mizoroki--Heck and Suzuki--Miyaura cross-coupling reactions with good diversity and generality. The catalysts could be easily recovered and reused several times without a significant loss in their catalytic activity and stability.


New Pd(Ii) And Pt(Ii)-Diaminophosphine Complexes Bearing Cyclohexyl Or Isopropyl Moiety: Use Of Pd(Ii) Complexes As Precatalyst In Mizoroki--Heck And Suzuki--Miyaura Cross-Coupling Reactions, Murat Aydemi̇r, Feyyaz Durap, Akin Baysal Jan 2015

New Pd(Ii) And Pt(Ii)-Diaminophosphine Complexes Bearing Cyclohexyl Or Isopropyl Moiety: Use Of Pd(Ii) Complexes As Precatalyst In Mizoroki--Heck And Suzuki--Miyaura Cross-Coupling Reactions, Murat Aydemi̇r, Feyyaz Durap, Akin Baysal

Turkish Journal of Chemistry

Two new diaminophosphine ligands, $N$,$N$'-bis(dicyclohexylphosphino)-2-(aminomethyl)aniline (1) and $N$,$N$'-bis(diisopropylphosphino)-2-(aminomethyl)aniline (2) were synthesized by the reaction of 2-(aminomethyl)aniline with two equivalents of Cy$_{2}$PCl or (iPr)$_{2}$PCl, respectively. The reactions of 1 and 2 with MCl$_{2}$(cod) (M = Pd, Pt; cod = 1,5-cyclooctadiene) yield complexes [cis-Pd(L$_{2}$PNHC$_{6}$H$_{4}$CH$_{2}$NHPL$_{2})$Cl$_{2}$] (L = Cy 3, iPr 4) and [cis-Pt(L$_{2}$PNHC$_{6}$H$_{4}$CH$_{2}$NHPL$_{2})$Cl$_{2}$] (L = Cy 5, iPr 6), respectively. The catalytic activity of the palladium complexes was investigated in the Suzuki-Miyaura cross-coupling reaction in the presence of Cs$_{2}$CO$_{3}$ as a base. The palladium complexes were also found to be highly active catalysts in the Mizoroki-Heck reaction.


Resorcinarene-Mono-Benzimidazolium Salts As Nhc Ligands For Suzuki--Miyaura Cross-Couplings Catalysts, Ümi̇t İşci̇, Muhi̇tti̇n Aygün, Resul Sevi̇ncek, Yunus Zorlu, Fabienne Dumoulin Jan 2015

Resorcinarene-Mono-Benzimidazolium Salts As Nhc Ligands For Suzuki--Miyaura Cross-Couplings Catalysts, Ümi̇t İşci̇, Muhi̇tti̇n Aygün, Resul Sevi̇ncek, Yunus Zorlu, Fabienne Dumoulin

Turkish Journal of Chemistry

Two mono-benzimidazolium salts of resorcinarene have been prepared and used as ligands in Suzuki--Miyaura cross-coupling reactions. They have been fully characterized by $^{1}$H and $^{13}$C NMR, MALDI, and FT-IR spectroscopic methods, and their structures were confirmed by X-ray diffraction analysis. These two new resorcinarene-based mono-benzimidazolium salts showed good catalytic activity for coupling reactions in DMF. The highest conversion was achieved for arylation of 4-bromotoluene using the resorcinarenyl mono-dimethylbenzimidazolium salt.


The Synthesis, Characterization, And Catalytic Properties Of ($\Kappa ^{2}-C,N)$-Palladacycles With N-Heterocyclic Carbene-Based Ancillary Ligands, Muhammet Emi̇n Günay, Gülcan Gençay Çoğaşlioğlu, Ruki̇ye Firinci Jan 2015

The Synthesis, Characterization, And Catalytic Properties Of ($\Kappa ^{2}-C,N)$-Palladacycles With N-Heterocyclic Carbene-Based Ancillary Ligands, Muhammet Emi̇n Günay, Gülcan Gençay Çoğaşlioğlu, Ruki̇ye Firinci

Turkish Journal of Chemistry

Novel five-membered ($\kappa ^{2}-C,N)$-palladacyclic complexes were prepared from the reaction of the corresponding acetate-bridged palladacycle dimer with N-heterocyclic carbene (NHC) ligands in high yields. Palladacyclic complexes (3) were fully characterized by elemental analysis and $^{1}$H and $^{13}$C NMR spectroscopy. Palladacyclic complexes were tested as catalyst for the C-C bond forming reaction. These complexes were found to be efficient catalysts for the Suzuki-Miyaura reaction of aryl bromides.


Secondary Metabolites From Sambucus Ebulus, İrem Atay, Hasan Kirmizibekmez, Ahmet Ceyhan Gören, Erdem Yeşi̇lada Jan 2015

Secondary Metabolites From Sambucus Ebulus, İrem Atay, Hasan Kirmizibekmez, Ahmet Ceyhan Gören, Erdem Yeşi̇lada

Turkish Journal of Chemistry

A new nonglycosidic iridoid, sambulin B (1), was isolated from the methanol extract of Sambucus ebulus L. leaves along with a recently reported new nonglycosidic iridoid, 10-O-acetylpatrinoside aglycone (sambulin A) (2); 2 flavonoids, isorhamnetin-3-O-\beta-D-glucopyranoside (3) and isorhamnetin-3-O-rutinoside (4); and a mixture of 2 flavonoids (5), quercetin-3-O-\beta-D-glucopyranoside and quercetin-3-O-\beta-D-galactopyranoside. Their structures were elucidated by 1-D and 2-D nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS) experiments.


Amperometric Biosensing Of Ethanol Based On Integration Of Alcohol Dehydrogenase With A Pt/Ppy--Pvs/Mb Electrode, Özlem Çolak, Fatma Arslan Jan 2015

Amperometric Biosensing Of Ethanol Based On Integration Of Alcohol Dehydrogenase With A Pt/Ppy--Pvs/Mb Electrode, Özlem Çolak, Fatma Arslan

Turkish Journal of Chemistry

A novel amperometric ethanol biosensor with alcohol dehydrogenase (ADH) and nicotinamide adenine dinucleotide (NAD^+) on polypyrrole--polyvinylsulfonate (PPy-PVS) film was accomplished. Meldola's blue (MB) was used as a mediator; it can facilitate the electron transfer that involves a chemical interaction between the electrode surface and NADH. Determination of ethanol was carried out by the oxidation of MB at --0.072 V vs. Ag/AgCl. The effects of pH and temperature were investigated and optimum parameters were found to be 7.0 and 40 °C, respectively. There are 2 linear parts at 1.0 \mu M--10.0 \mu M (R^2 = 0.993) and 0.01 mM--0.1 mM (R^2 …


Purification And Characterization Of Nadph-Cytochrome P450 Reductase From Lake Van Fish Liver Microsomes And Investigation Of Some Chemical And Metals' Effects On The Enzyme Activity, Müslüm Kuzu, Mehmet Çi̇ftci̇ Jan 2015

Purification And Characterization Of Nadph-Cytochrome P450 Reductase From Lake Van Fish Liver Microsomes And Investigation Of Some Chemical And Metals' Effects On The Enzyme Activity, Müslüm Kuzu, Mehmet Çi̇ftci̇

Turkish Journal of Chemistry

NADPH-cytochrome P450 reductase was purified from Lake Van fish liver microsomes by primary and secondary DEAE-cellulose column chromatograph with 20.46 \mu M/min/mg enzyme specific activities, 54.4% purification yield, and purification of 38-fold. The purity of the enzyme was established, and its monomer molecular weight was determined by SDS-polyacrylamide gel electrophoresis. SDS-PAGE results showed a single band and the molecular weight of NADPH-cytochrome P450 reductase was 70 kDa. In addition, optimum ionic strength, optimum pH, optimum temperature, and stable pH values were determined for the enzyme in the kinetic studies performed. K_M and V_{max} were determined for NADPH and cytochrome c. …


Synthesis Of Methyl 4-(9h-Carbazole-9-Carbanothioylthio) Benzoate: Electropolymerization And Impedimetric Study, Murat Ateş, Nesi̇mi̇ Uludağ, Fati̇h Arican, Tolga Karazehi̇r Jan 2015

Synthesis Of Methyl 4-(9h-Carbazole-9-Carbanothioylthio) Benzoate: Electropolymerization And Impedimetric Study, Murat Ateş, Nesi̇mi̇ Uludağ, Fati̇h Arican, Tolga Karazehi̇r

Turkish Journal of Chemistry

Methyl 4-((9H-(carbazole-9-carbanothioylthio) benzoate (MCzCTB) was chemically synthesized and characterized by FTIR, ^1H NMR, and ^{13}C NMR. A novel synthesized monomer was electropolymerized on a glassy carbon electrode (GCE) in various initial molar concentrations of [MCzCTB]_0= 1, 3, 5, and 10 mM in 0.1 M NaClO_4/CH_3CN and 1 M H_2SO_4. P(MCzCTB)/GCE was characterized by cyclic voltammetry, Fourier transform infrared-attenuated transmittance reflectance, scanning electron microscopy-energy dispersive X-ray, and electrochemical impedance spectroscopy. The capacitive behavior of the modified electrode was obtained by Nyquist, Bode-magnitude, and Bode-phase plots. The highest capacitance at low frequency was obtained as \sim 53.1 mF cm^{-2} from Nyquist plot …


Synthesis, Structural Characterization, And Antimicrobial Efficiency Of Sulfadiazine Azo-Azomethine Dyes And Their Bi-Homonuclear Uranyl Complexes For Chemotherapeutic Use, Abdalla M. Khedr, Fawaz A. Saad Jan 2015

Synthesis, Structural Characterization, And Antimicrobial Efficiency Of Sulfadiazine Azo-Azomethine Dyes And Their Bi-Homonuclear Uranyl Complexes For Chemotherapeutic Use, Abdalla M. Khedr, Fawaz A. Saad

Turkish Journal of Chemistry

Two sulfadiazine azo-azomethine dyes containing two active coordination centers and their bi-homonuclear UO_2(II)-complexes were synthesized for potential chemotherapeutic use. The ligands were prepared, starting from the coupling of sulfadiazine dizonium salt with acetylacetone, followed by condensation with ethylenediamine and 1,6-hexanediamine (HL^I and HL^{II}) using a modified literature procedure. The structures of the ligands and their UO_2(II)-complexes were elucidated by conventional and thermal gravimetric analyses, molar conductivity, magnetic susceptibility, and IR, UV-Vis, ^1H NMR, and mass spectra. The analytical and spectral data supported the binuclear formulation of the complexes with a 2:1 metal to ligand ratio and octahedral geometry. The molar …


The Synthesis Of 1,3-Dialkyl-4-Methylimidazolinium Salts And Their Application In Palladium Catalyzed Heck Coupling Reactions, Murat Yi̇ği̇t, Güli̇n Bayam, Beyhan Yi̇ği̇t, İsmai̇l Özdemi̇r Jan 2015

The Synthesis Of 1,3-Dialkyl-4-Methylimidazolinium Salts And Their Application In Palladium Catalyzed Heck Coupling Reactions, Murat Yi̇ği̇t, Güli̇n Bayam, Beyhan Yi̇ği̇t, İsmai̇l Özdemi̇r

Turkish Journal of Chemistry

Seven novel 1,3-dialkyl-4-methylimidazolinium chloride salts 3a--g were prepared as precursors of N-heterocyclic carbenes by reacting N,N'-alkyl-1,2-diaminopropane, triethyl orthoformate, and ammonium chloride. The salts were characterized spectroscopically. The in situ prepared palladium complexes derived from the imidazolinium salts and palladium acetate were used as catalyst in Heck coupling reactions between aryl bromides and styrene. The corresponding Heck products were obtained in good yields.


Selective Co Methanation Over Nio--Al_2o_3--Zro_2 And Co_3o_4--Al_2o_3--Zro_2 Catalysts, Fi̇li̇z Derekaya, Derya Ermergen Jan 2015

Selective Co Methanation Over Nio--Al_2o_3--Zro_2 And Co_3o_4--Al_2o_3--Zro_2 Catalysts, Fi̇li̇z Derekaya, Derya Ermergen

Turkish Journal of Chemistry

NiO--Al_2O_3--ZrO_2 and Co_3O_4--Al_2O_3--ZrO_2 catalysts were prepared by three different co-precipitation methods, namely co-precipitation, surfactant-assisted co-precipitation, and surfactant-assisted co-precipitation with ultrasound mixing methods, and their activities were tested in selective CO methanation. Catalysts were characterized using N_2 physisorption, XRD, SEM, TEM, XPS, and TPR-H_2 techniques. CO methanation and selective CO methanation reactions were carried out. Catalysts prepared by surfactant assisted co-precipitation gave high surface area, uniform pore size distributions, and small pores. The NiO--Al_2O_3--ZrO_2 catalyst prepared by surfactant-assisted co-precipitation gave 50% CO conversion to CH_4 at 155 °C and all CO converted to CH_4 when T > 225 °C. For the selective …


Redox Polymerization Of N-Isopropylacrylamide By Using Hydroxylated Soya Oil Polymer, Abdulkadi̇r Alli, Ti̇mur Şanal, Baki̇ Hazer Jan 2015

Redox Polymerization Of N-Isopropylacrylamide By Using Hydroxylated Soya Oil Polymer, Abdulkadi̇r Alli, Ti̇mur Şanal, Baki̇ Hazer

Turkish Journal of Chemistry

Water soluble hydroxylated soya oil polymer was used in the redox polymerization of N-isopropylacrylamide (NIPAM) in order to obtain water-based hydroxylated-soya oil polymer-g-PNIPAM graft copolymer. For this purpose, soya oil was exposed to air under sunlight to obtain autoxidized soya oil polymer (PSy-ox). PSy-ox was allowed to react with diethanol amine to obtain hydroxylated soya oil polymer (hydroxylated-PSy). An ammonium persulfate with hydroxylated-PSy redox initiating system was used in the polymerization of NIPAM in order to obtain thermo-responsive hydroxylated-PSy-g-PNIPAM water-based graft copolymers. The graft copolymers were characterized using proton nuclear magnetic resonance, Fourier transform infrared~spectroscopy, gel permeation chromatography, thermal gravimetric …


Gaseous And Dissolved Oxygen Sensing With Stabilized Pyrene In Ionic Liquid Modified Electrospun Slides, Özlem Öter, Gülhan Sabanci Şahi̇n Jan 2015

Gaseous And Dissolved Oxygen Sensing With Stabilized Pyrene In Ionic Liquid Modified Electrospun Slides, Özlem Öter, Gülhan Sabanci Şahi̇n

Turkish Journal of Chemistry

Pyrene dye has many superior characteristics for oxygen sensing studies such as long fluorescence lifetime, high quantum yield, and good sensitivity. It is preferred in some cases over ruthenium dyes for its more lipophilic character and higher sensitivity. However, easy photodegradation of pyrene is a challenging problem. In this study, pyrene dye was for the first time immobilized in an ethyl cellulose matrix and used for oxygen sensing in the form of thin films and electrospun sensing slides. The hydrophobic ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate was used as additive for the first time for dissolved oxygen sensing studies. The oxygen sensitivity …