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Effect Of Polyoxyethylene Chain Length And Electrolyte On The Viscosity Of Mixed Micelles, Hali̇de Akbaş, Tali̇ha Si̇di̇m, Mehmet İşcan
Effect Of Polyoxyethylene Chain Length And Electrolyte On The Viscosity Of Mixed Micelles, Hali̇de Akbaş, Tali̇ha Si̇di̇m, Mehmet İşcan
Turkish Journal of Chemistry
The viscosity measurements of micelles composed of mixtures of anionic/nonionic surfactants were carried out as a function of the mole fraction of surfactants. The systems studied were sodium dodecyl sulfate (SDS)-polyoxyethylene lauryl ether (C_{12}POE_{n} n = 4, 10 and 23) in water and 0.1 M sodium chloride solution. In the single systems, the relative viscosity of nonionic surfactant is greater than that of SDS, and increases with the increasing level of ethylene oxide. In the mixed surfactant systems, the relative viscosities vary at the mixed molar fraction of SDS, between 0.2 and 0.3, and then the relative viscosities of mixed …
Purification And Characterization Of Glucose 6-Phosphate Dehydrogenase From Sheep Liver, Vedat Türkoğlu, Si̇nan Aldemi̇r, Mehmet Çi̇ftçi̇
Purification And Characterization Of Glucose 6-Phosphate Dehydrogenase From Sheep Liver, Vedat Türkoğlu, Si̇nan Aldemi̇r, Mehmet Çi̇ftçi̇
Turkish Journal of Chemistry
Glucose 6-phosphate dehydrogenase (D-glucose 6-phosphate: NADP^{+} oxidoreductase, EC 1.1.1.49; G6PD) was purified from sheep liver by a simple and rapid method. The purification process consisted of two steps: preparation of the homogenate, and 2', 5'-adenosine diphosphate (ADP) Sepharose 4B affinity chromatography. Through the use of these two consecutive steps, the enzyme was purified with a yield of 35.6% and 1,920 fold, having the specific activity of 11.2 enzyme units (EU/mg protein). A K_{M} of 0.176 mM and a V_{\max} of 0.0179 EU/ml were obtained for G6-P, and 0.0194 mM and 0.0223 EU/ml for NADP^{+}. Enzymatic activity was measured spectrophotometrically according …
The Effect Of Tert-Butylhydroperoxide On The Thiol Redox Status In Human Erythrocytes And The Protective Role Of Glucose And Antioxidants, Yasemi̇n Aksoy, İ. Hamdi̇ Öğüş, Nazmi̇ Özer
The Effect Of Tert-Butylhydroperoxide On The Thiol Redox Status In Human Erythrocytes And The Protective Role Of Glucose And Antioxidants, Yasemi̇n Aksoy, İ. Hamdi̇ Öğüş, Nazmi̇ Özer
Turkish Journal of Chemistry
For survival, living cells maintain their thiol redox status within acceptable limits by three different mechanisms: i. glutathione disulfide export, ii. reduction of glutathione disulfide by pentose phosphate pathway and, iii. reduction of glutathione disulfide by Protein-SH. To assess the relative contribution of each one of the systems, intracellular [glutathione], [glutathione disulfide] and their export, in fresh and aged erythrocytes subjected to oxidative stress, in \pm glucose and \pm antioxidants, were measured. Glutathione was rapidly oxidized by tert-butylhydroperoxide in \pm glucose in both groups. The regeneration of glutathione, in both groups, in \pm glucose was about 100 and 50%, respectively. …
Synthesis Of New Antimicrobial Agents; Amide Derivatives Of Pyranones And Pyridinones, Mutlu Di̇lsi̇z Aytemi̇r, Robert C. Hider, Di̇lek Demi̇r Erol, Meral Özalp, Meli̇ke Eki̇zoğlu
Synthesis Of New Antimicrobial Agents; Amide Derivatives Of Pyranones And Pyridinones, Mutlu Di̇lsi̇z Aytemi̇r, Robert C. Hider, Di̇lek Demi̇r Erol, Meral Özalp, Meli̇ke Eki̇zoğlu
Turkish Journal of Chemistry
In this study, 4(1H)-pyridinones with an amide function in Position 2 of the pyridinone ring showed antimicrobial activity. The synthesis and the biological properties of some novel amide derivatives of pyran-4(1H)-one and 4(1H)-pyridinone have been reported. Amide derivatives of pyran-4(1H)-one and 4(1H)-pyridinone were prepared using two different methods. Antimicrobial activities were determined as MIC values using the microdilution broth method against the bacteria Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa and the fungi Candida albicans, Candida krusei and Candida parapsilosis. Compounds 6 and 9 exhibited the best inhibitor activity against S. aureus.
Voltammetric And Flow Injection Amperometric Determination Of Cysteine At A Glassy Carbon Electrode In The Presence Of Copper(Ii) Ions, Zekerya Dursun, İlyas Şahbaz, F. Ni̇l Ertaş, Gürel Ni̇şli̇
Voltammetric And Flow Injection Amperometric Determination Of Cysteine At A Glassy Carbon Electrode In The Presence Of Copper(Ii) Ions, Zekerya Dursun, İlyas Şahbaz, F. Ni̇l Ertaş, Gürel Ni̇şli̇
Turkish Journal of Chemistry
The voltammetric behaviour of cysteine was investigated in the presence of Cu(II) ions at a rotating glassy carbon electrode (RGCE). Two reduction peaks related to the successive reduction of the cysteine complexes of Cu(II) and Cu(I) ions were observed at --0.30 and --0.60 V vs. SCE respectively. These peaks were increased upon the addition of cysteine into a pH 9.20 borate buffer solution containing 0.1 M KNO_{3} and 1.0 x 10^{-5} M Cu(II) ions. The calibration curve was linear in the concentration range of 5.0 x 10^{-10}- 2.0 x 10^{-8} M for cysteine by utilising the peak current at --0.6 …
Differential Pulse Polarographic Determination Of Cadmium After Solid Liquid Extraction And Preconcentration Using Pan, Mohammad Ali Taher
Differential Pulse Polarographic Determination Of Cadmium After Solid Liquid Extraction And Preconcentration Using Pan, Mohammad Ali Taher
Turkish Journal of Chemistry
A highly selective, sensitive, rapid and economical differential pulse polarographic method has been developed for the determination of trace amounts of cadmium in various samples after the adsorption of its 1-(2-pyridylazo)-2-naphthol (PAN) complex on microcrystalline naphthalene in the pH range of 8.2-11.0. After filtration, the solid mass is shaken with 9.0 mL of 1 M hydrochloric acid and cadmium is determined by differential pulse polarography. Cadmium can alternatively be quantitatively adsorbed on [1-(2-pyridylazo)-2-naphthol]-naphthalene adsorbent packed in a column and determined similarly. The detection limit is 0.07 \mu g/mL (signal-to noise ratio = 2) and the linearity is maintained in the …
Thermogravimetric Characterization Of Turkish Bituminous Coals For Combustion, Sai̇t Kizgut, Di̇lek Cuhadaroğlu, İhsan Toroğlu
Thermogravimetric Characterization Of Turkish Bituminous Coals For Combustion, Sai̇t Kizgut, Di̇lek Cuhadaroğlu, İhsan Toroğlu
Turkish Journal of Chemistry
This study focused on the thermal gravimetric characterization of Turkish bituminous coals for combustion. The combustion properties considered were based on the burning profile of coal samples and their chars produced in a PL 1500 TGA apparatus. The coal seam samples used in the study were obtained from TTK (Turkish Hardcoal Enterprise) mines as channel samples. The majority of the samples from 12 seams were medium-volatile bituminous and only three of them were high-volatile bituminous. Combustion profile parameters of coal samples and chars were correlated with petrographic, proximate and ultimate analysis data in order to establish the combustion differences of …
Dna Cleavage Activity Of Diazonium Salts: Chemical Nucleases, Murat Kizil, Ebru İnce Yilmaz, Necmetti̇n Pi̇ri̇nççi̇oğlu, Çeti̇n Ayteki̇n
Dna Cleavage Activity Of Diazonium Salts: Chemical Nucleases, Murat Kizil, Ebru İnce Yilmaz, Necmetti̇n Pi̇ri̇nççi̇oğlu, Çeti̇n Ayteki̇n
Turkish Journal of Chemistry
4-Fenoldiazonium tetrafluoroborate and 4-benzoicaciddiazonium tetrafluoroborate was prepared and was shown to be an effective DNA cleavage agent in the presence of the 1-electron donor copper(II) chloride. Its mechanism involves the generation of the aryl radical cleaving DNA by hydrogen atom abstraction from deoxyribose sugar.
Study On Papain Immobilization On A Macroporous Polymer Carrier, Liang Ding, Zihua Yao, Tong Li, Qiang Yue, Jia Chai
Study On Papain Immobilization On A Macroporous Polymer Carrier, Liang Ding, Zihua Yao, Tong Li, Qiang Yue, Jia Chai
Turkish Journal of Chemistry
Macroporous resin microbeads of methyl methacrylate-divinyl benzene copolymer were synthesized by radical suspension polymerization of acrolein with divinylbenzene in the presence of a pore-creating agent, petroleum ether. The microbeads had a large specific surface area and large pores covered the entire surface of the resin. This macroporous polymer carrier was aminated by hydrazine hydrate that produced a large number of amino groups on the carrier. Papain was immobilized on the porous polymer carrier by glutaraldehyde cross-linking or diazo-coupling. The factors involved in the activity recovery of the immobilized papain and the enzymic properties of the resulting immobilized papain were studied …
Synthesis, Characterization And Biological Applications Of Organotin(Iv) Derivatives Of 2-(2-Fluoro-4-Biphenyl)Propanoic Acid, Sohail Mahmood, Saqib Ali, Moazzam Hussain Bhatti, Mohammad Mazhar, Rashid Iqbal, Khalid Mohammed Khan, Ghulam Mustafa Maharvi
Synthesis, Characterization And Biological Applications Of Organotin(Iv) Derivatives Of 2-(2-Fluoro-4-Biphenyl)Propanoic Acid, Sohail Mahmood, Saqib Ali, Moazzam Hussain Bhatti, Mohammad Mazhar, Rashid Iqbal, Khalid Mohammed Khan, Ghulam Mustafa Maharvi
Turkish Journal of Chemistry
A series of organotin(IV) derivatives with the general formula R_{4 - n}SnL_{n} (where n = 1 or 2, R = Me, Et, n-Bu, Ph and L = 2-(2-fluoro-4-biphenyl)propanoate) have been synthesized and characterized by infrared, multinuclear NMR (^{1}H, ^{13}C, ^{119}Sn), ^{119m}Sn Mössbauer spectroscopy and mass spectrometry. Screening tests of these compounds showed that they are highly active against various bacteria and fungi.
Kinetics Of Oxidation Of Pyridylmethylsulphinylbenzimidazole By Cerium(Iv) In An Aqueous Perchloric Acid Medium, Dinesh C. Bilehal, Ravi̇raj M. Kulkarni, Sharanappa T. Nandibewoor
Kinetics Of Oxidation Of Pyridylmethylsulphinylbenzimidazole By Cerium(Iv) In An Aqueous Perchloric Acid Medium, Dinesh C. Bilehal, Ravi̇raj M. Kulkarni, Sharanappa T. Nandibewoor
Turkish Journal of Chemistry
The kinetics of oxidation of pyridylmethylsulphinylbenzimidazole [PMSB] by Ce(IV) in an aqueous perchloric acid medium at a constant ionic strength of 1.50 mol dm^{-3} were studied spectrophotometrically. The reaction showed first order kinetics with respect to Ce(IV) concentration and an apparent less than unit order dependence in [PMSB] and a zero order in [H^+]. The initial addition of products has no significant effect on the rate of the reaction. A possible mechanism is proposed here. The reaction constants involved in the mechanism have been computed. There is good agreement between the observed and calculated rate constants under different experimental conditions. …
Polyethyleneimine-Coated Capillaries For The Separation Of Dna By Capillary Electrophoresis, M. Sai̇d Nutku, F. Bedi̇a Eri̇m Berker
Polyethyleneimine-Coated Capillaries For The Separation Of Dna By Capillary Electrophoresis, M. Sai̇d Nutku, F. Bedi̇a Eri̇m Berker
Turkish Journal of Chemistry
A new capillary electrophoresis of DNA fragments has been achieved with the cooperative effects of the electrophoretic and electroosmotic mobilities realized via the polyethyleneimine (PEI) coating of the capillary walls. As a result, seven of the 11 different-sized DNA fragments have produced resolved CE peaks. Our results demonstrate that analyses of DNA constituents can be performed under a wide range of conditions by the appropriate tuning of the coating and filler within the capillary.
Synthesis Of Some New Benzimidazole Carbamate Derivatives For Evaluation Of Antifungal Activity, Canan Kuş, Nurten Altanlar
Synthesis Of Some New Benzimidazole Carbamate Derivatives For Evaluation Of Antifungal Activity, Canan Kuş, Nurten Altanlar
Turkish Journal of Chemistry
The synthesis and structure elucidation of methyl 5(6)-fluoro-6(5)-substituted-1H-benzimidazole carbamate derivatives are performed and their antifungal activities evaluated against Candida albicans.
Photochemical Reactions Of \Alpha-Terpinene And Acenaphthene Under Concentrated Sunlight, Nesi̇be Avcibaşi, Siddik İçli̇, Andrew Gilbert
Photochemical Reactions Of \Alpha-Terpinene And Acenaphthene Under Concentrated Sunlight, Nesi̇be Avcibaşi, Siddik İçli̇, Andrew Gilbert
Turkish Journal of Chemistry
\alpha-Terpinene was successfully dehydrogenated to p-cymene in photocatalytic reaction with benzophenone and cupric ions under 40 suns concentrated sunlight irradiation, proving that photodehydrogenation reactions may be employed for the synthesis of fine chemicals under sunlight. Acenaphthene dehydrogenation under concentrated sunlight resulted in the minor formation of acenaphthylene and the quantitative formation of acenaphthenone when the solution was aerated. Stable benzylic-type radical intermediates are thought to lower the yield of dehydrogenation reactions.
Search For A Nonelectrocyclic Cyclization Of Nitrosostyrene: Rearrangements Of Michael Adducts From Dmad And \Alpha-Dialkylamino Oximes, Necdet Coşkun, Nevi̇n Arikan
Search For A Nonelectrocyclic Cyclization Of Nitrosostyrene: Rearrangements Of Michael Adducts From Dmad And \Alpha-Dialkylamino Oximes, Necdet Coşkun, Nevi̇n Arikan
Turkish Journal of Chemistry
The aza-Claisen rearrangement product of the Michael adducts 2 from \alpha-dialkylaminoacetophenone oximes and DMAD underwent fragmentation to give dialkylaminomaleate, and benzonitrile at reflux in acetonitrile. The fragmentation was assumed to proceed through an unstable 4H-1,2-oxazete 6. The same reaction performed at room temperature, in addition to the nitrile and maleate, gave the corresponding 2-(2-dialkylamino-1-phenylethylideneaminooxy)-but-2- enedioic acid dimethyl esters 8 and 9. Compounds 9 isomerized to 8 on heating in acetonitrile.
Thermal Decomposition Kinetics Of Anilino-P-Chlorophenylglyoxime Complexes Of Cobalt (Ii), Nickel (Ii) And Copper (Ii), Hakan Arslan, Nevzat Külcü, Ali̇ İhsan Pekacar
Thermal Decomposition Kinetics Of Anilino-P-Chlorophenylglyoxime Complexes Of Cobalt (Ii), Nickel (Ii) And Copper (Ii), Hakan Arslan, Nevzat Külcü, Ali̇ İhsan Pekacar
Turkish Journal of Chemistry
The Co(II), Ni(II) and Cu(II) complexes of anilino-p-chlorophenylglyoxime were synthesised. The thermal behaviour of all complexes was studied by DTA and TG. It was found that pyrolytic decomposition occurs with melting in metal complexes and that metal oxides remain as final products of the metal complexes. A GC-MS combined system was used to identify the products during pyrolytic decomposition. The pyrolytic end products were identified by x-ray powder diffraction. The orders, n, the activation energies, E^*, the pre-exponential factors, A, and the entropies, \Delta S^*, of thermal decomposition reactions were derived from thermogravimetric and differential thermogravimetric curves. The kinetic analysis …
Differential Pulse Polarographic Determination Of Enalapril Maleate, Fi̇kri̇ye Elmali, Güzi̇n Alpdoğan, Şule Aycan, Sidika Sungur
Differential Pulse Polarographic Determination Of Enalapril Maleate, Fi̇kri̇ye Elmali, Güzi̇n Alpdoğan, Şule Aycan, Sidika Sungur
Turkish Journal of Chemistry
A differential pulse polarographic (DPP) method has been developed for the quantitative analysis of enalapril maleate. Enalapril maleate gives a peak at -1.4 V in methanol. A calibration curve was constructed for the 20 -100 \mu g ml^{-1} concentration range. As a reference method, a reversed phase high performance liquid chromatographic procedure has been developed. Commercially available tablets were analysed by the two methods. Statistical evaluations indicated that there was no significant difference between the mean values and precisions of the two methods at a 95\% confidence level.
^1h Nmr Studies Of Some Imidazole Ligands Coordinated To Co(Iii), Kosrow Zamani, Akbar Mobinikhaledi, Naser Foroughifar, Khalil Faghihi, Vahid Mahdavi
^1h Nmr Studies Of Some Imidazole Ligands Coordinated To Co(Iii), Kosrow Zamani, Akbar Mobinikhaledi, Naser Foroughifar, Khalil Faghihi, Vahid Mahdavi
Turkish Journal of Chemistry
Chemical shifts for proton signals of an imidazole ring coordinated to Co(III) move downfield as the total complex charge increases. However, the C_{(2) - H} chemical shift of the imidazole ring in cis-[Co(en)_{2}(N-mIm) OPO_{3}H]°, which has no charge compared to those of cis-[Co(en)_{2}(N-mIm) OPO_{3}H]^{+} and cis}-[Co(en)_{2}(N-mIm) OPO_{3}H_{2}]^{2 +} , moves downfield. These unexpected phenomena could be attributed to an intramolecular interaction between the phosphate anion group and C_{(2) - H} of the imidazole ligand.
Conductimetric And Potentiometric Investigation Of Effects Of Solvents And Titrant On Formation Of Homoconjugates, Esi̇n Canel, Mustafa Taşteki̇n, Orhan Atakol, Esma Kiliç
Conductimetric And Potentiometric Investigation Of Effects Of Solvents And Titrant On Formation Of Homoconjugates, Esi̇n Canel, Mustafa Taşteki̇n, Orhan Atakol, Esma Kiliç
Turkish Journal of Chemistry
Trichloro-, tribromo- and trifluoro- acetic acids were both conductimetrically and potentiometrically titrated in acetonitrile and 2-propanol media. The titrations were carried out at 25°C under nitrogen atmosphere and titrants used were the solutions of triethyl, di-n-butyl and n-butyl amines prepared in the same solvents. Whether these acids gave a homoconjugation reaction during titration was investigated by the use of conductimetric and potentiometric titration curves. In acetonitrile media trichloro- and tribromo-acetic acids decomposed to give chloroform and carbon dioxide, and bromoform and carbon dioxide respectively. It was observed that the acid concentration and the type of titrant used had no effect …
Kinetics Of Polymerization Of 2-Hydroxyethylmethacrylate Initiated By A Titanium(Iii)-Dimethylglyoxime Redox System, Kalappa Prashantha, K. V. Kumar Pai, M. Puttegowda Yashoda, B. Sheena Sherigara
Kinetics Of Polymerization Of 2-Hydroxyethylmethacrylate Initiated By A Titanium(Iii)-Dimethylglyoxime Redox System, Kalappa Prashantha, K. V. Kumar Pai, M. Puttegowda Yashoda, B. Sheena Sherigara
Turkish Journal of Chemistry
The polymerization of 2-hydroxyethylmethacrylate (HEMA) initiated by the redox system titanium(III)-dimethyl glyoxime (DMG) was studied in dimethyl formamide (DMF)-water (80:20 v/v) medium in the temperature range 290-310 K. The rate of polymerization (R_{p}) was investigated at various concentrations of reductant, oxidant, sulfuric acid, and monomer. Cyclic voltametric sensing of dimethylglyoxime under the kinetic conditions demonstrated its reduction behavior. From the obtained results, it was inferred that the polymerization reaction was initiated by an organic free radical arising from the titanium(III)-dimethylglyoxime redox system. Chain termination of the polymer took place predominantly by mutual coupling and small fraction by chain transfer mechanism …
Synthesis Of Some New Substituted 1,2,4-Triazole And 1,3,4-Thiadiazole And Their Derivatives, Khosrow Zamani, Khalil Faghihi, M. Reza Sangi, Javad Zolgharnein
Synthesis Of Some New Substituted 1,2,4-Triazole And 1,3,4-Thiadiazole And Their Derivatives, Khosrow Zamani, Khalil Faghihi, M. Reza Sangi, Javad Zolgharnein
Turkish Journal of Chemistry
Several 5-(isomeric pyridyl)-4-aryl-1,2,4-triazole-3-thiol/yl-thiomethyl/yl-thioethyl/yl-thiobenzyl and yl-thioglycolic acids were prepared as possible biologically active agents. The infrared, nuclear magnetic resonance (^{1}H-NMR and ^{13}C-NMR), mass spectra and elemental analysis of these compounds are reported
Purification And Partial Characterization Of Catalase From Chicken Erythrocytes And The Effect Of Various Inhibitors On Enzyme Activity, Tüli̇n Aydemi̇r, Kevser Kuru
Purification And Partial Characterization Of Catalase From Chicken Erythrocytes And The Effect Of Various Inhibitors On Enzyme Activity, Tüli̇n Aydemi̇r, Kevser Kuru
Turkish Journal of Chemistry
Catalase plays a major role in the protection of tissues from the toxic effects of H_{2}O_{2} and partially reduced oxygen species. A nearly 136-fold enzyme purification was obtained from chicken erythrocyte by acetone precipitation, ethanol-chloroform treatment, CM-cellulose and Sephadex G-200 chromatography. The specific activity of purified enzyme was 42,556 U/mg. The molecular weight of the native chicken erythrocyte catalase was estimated at 240 kDa by gel filtration. SDS-gel electrophoresis results indicated that chicken erythrocyte catalase consists of four apparently identical subunits, with a molecular weight of around 57.5 kDa. The optical spectrum of the purified enzyme shows a Soret band …
A Novel Silver Recovery Method From Waste Photographic Films With Naoh Stripping, Nuri̇ Naki̇boğlu, Duygu Toscali, Gürel Ni̇sli̇
A Novel Silver Recovery Method From Waste Photographic Films With Naoh Stripping, Nuri̇ Naki̇boğlu, Duygu Toscali, Gürel Ni̇sli̇
Turkish Journal of Chemistry
A novel, simple, fast, cheap and pollution-free method was developed for recovering the silver from waste X-ray photographic films with NaOH stripping. The method has a number of advantages because it obviates the need for burning, oxidizing, electrolysis or purifying steps. Moreover, all experiments were carried out in the same flask, unlike other techniques. Silver recovery conditions were optimized and silver a purity level of 99\% was recovered. The metal impurities (Al, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Sn) in the recovered silver were determined using the ICP-MS method. The results were compared with results in …
Chromatographic Determination Of Phenolic Acids In The Snowdrop By Hplc, Mustafa Tüzen, Mustafa Özdemi̇r
Chromatographic Determination Of Phenolic Acids In The Snowdrop By Hplc, Mustafa Tüzen, Mustafa Özdemi̇r
Turkish Journal of Chemistry
Free and esterified phenolic acids of Galanthus elwesii (snowdrop) were extracted with petroleum ether and determined by HPLC. Cinnamic, ferulic, vanillic, p-coumaric, p-hydroxy benzoic, and caffeic acids were detected by a linear gradient elution with acetic acid/water (2:98 v/v) and acetic acid/acetonitrile/water (2:30:68 v/v) as the mobile phases in 30 min with a flow rate of 1.5 mL/min. Among the acids from snowdrop extracts, p-hydroxy benzoic was the major constituent followed by vanillic and ferulic acids.
Electrochemical Behaviour Of Thymolphthalein, Mustafa Uçar, Necati̇ Menek
Electrochemical Behaviour Of Thymolphthalein, Mustafa Uçar, Necati̇ Menek
Turkish Journal of Chemistry
The polarographic and voltammetric behaviour of thymolphthalein in ethanol-water (1/5 v/v) was studied using various electrochemical techniques. The reduction of thymolphthalein on a mercury drop electrode was investigated. The adsorption effect on the electrode surface was observed. The rate constants for the electron transfer steps were determined by and without taking adsorption into occount using the Laviron technique and Nicholson technique respectively. The diffusion coefficients were calculated from the cyclic voltammetric data using the method developed by Garrido. Reversibility for the electrode reaction was investigated and a mechanism for the electrode reaction was proposed.
Studies On The Mechanism Of Base-Catalyzed Decomposition Of Bicyclic Endoperoxides, Ebru Mete, Ramazan Altundaş, Hasan Seçen, Meti̇n Balci
Studies On The Mechanism Of Base-Catalyzed Decomposition Of Bicyclic Endoperoxides, Ebru Mete, Ramazan Altundaş, Hasan Seçen, Meti̇n Balci
Turkish Journal of Chemistry
Kinetic studies were performed to clarify the Kornblum-Delamare reaction mechanism of bicyclic endoperoxides. Ascaridol and 1,4-diphenyl-2,3-dioxa-bicyclo[2.2.2]oct-5-ene, not having \alpha -protons, did not provide any reaction with bases. Reaction with different bases has revealed that reaction rates for the base-catalyzed decomposition of 2,3-dioxa-bicyclo[2.2.2]oct-5-ene depend strongly on the base strength. The stronger the base used, the faster the conversion rate. Reaction rate values k of endoperoxides with different skeletons were also studied with NEt_{3}. It has been noted that the strength of the base plays the dominant role in determining the rate of the reactions.
Bromination Of Tricyclo[7.2.1.0^{2,7}]Dodeca-2,4,6,10-Tetraene Derivatives: Highly Brominated Benzobicyclic Systems, Ari̇f Daştan
Bromination Of Tricyclo[7.2.1.0^{2,7}]Dodeca-2,4,6,10-Tetraene Derivatives: Highly Brominated Benzobicyclic Systems, Ari̇f Daştan
Turkish Journal of Chemistry
The bromination reaction of tricyclo[7.2.1.0^{2,7}]dodeca- 2,4,6,10-tetraene derivatives was studied and the possible role of a substituent in rearrangements is discussed.