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1.
Saracoglu N Talaz O Azizoglu A Watson WH Balci M 《The Journal of organic chemistry》2005,70(14):5403-5408
[reaction: see text] endo- and exo-2,3,4,7-tetrahydro-1H-1,4-methanobenzocycloheptene-7-carboxylic acid ethyl esters have been synthesized, and their Diels-Alder cycloaddition reactions with maleic anhydride, dimethyl acetylenedicarboxylate and singlet oxygen have been investigated. The X-ray analysis of four adducts indicated the pyramidalization of the central double bond. Density functional theory calculations on the isolated products and model compounds showed excellent agreement between the experimental and theoretical determined butterfly angles. Furthermore, it has been shown that a cyclopropyl group fused to [2.2.2] system decreases significantly the degree of the pyramidalization which is attributed to the steric interactions between the cyclopropyl group and ethano bridge of the norbornene systems. Due to the instability of the bicyclic endoperoxides, their X-ray analysis could not be carried out. DFT calculations on model compounds showed increased bending in the case of the product obtained by the addition of singlet oxygen to endo-2,3,4,7-tetrahydro-1H-1,4-methanobenzocycloheptene-7-carboxylic acid ethyl ester. 相似文献
2.
Sinan Bayindir Esra Erdogan Haydar Kilic Omer Aydin Nurullah Saracoglu 《Journal of heterocyclic chemistry》2015,52(5):1589-1594
A survey of redox aminations of indoline with aliphatic ketones using bismuth nitrate as catalyst is described. A reaction of an equivalent amount of indoline and aliphatic cyclic and acyclic ketones provides a mixture of excessive alkylated indole derivatives over typically redox isomerization and reductive alkylation pathways while using of the five equivalent of indoline provides N‐alkylated indolines as a reductive alkylation product. The desired N‐alkyl indoles from the oxidation of N‐alkyl indolines were obtained in excellent yields. 相似文献
3.
Redox Amination Scope of Benzylic Ketones with Indoline: Synthetic and Mechanistic Insights 下载免费PDF全文
Omer Aydin Haydar Kilic Sinan Bayindir Esra Erdogan Nurullah Saracoglu 《Journal of heterocyclic chemistry》2015,52(5):1540-1553
Bi(NO3)3·5H2O‐Catalyzed redox amination scope and mechanistic insights of benzylic ketones with indoline are discussed. The experimental results demonstrate that the formation of N‐alkyl‐substituted indole/indoline derivatives over typically competitive redox and reductive amination processes is depending upon the reaction condition for the benzylic ketones. 相似文献
4.
An experimental study of runaway electrons in the EAST tokamak has been performed by a recently developed multi‐channel hard x‐ray diagnostics based on NaI(TL) scintillator detectors. It is found that in the current quench phase, the inductive loop voltage plays an important role in the generation of runaway electrons. And the avalanche mechanism was the main mechanism for runaway electrons after the disruptions. The distribution and transportation of runaway electrons were also investigated by multi‐channel hard x‐ray diagnostics. It is also found that the intensity of runaway electrons emission in the core plasma was much higher than those in the downside of the cross‐section, while the emission intensity of runaway electrons in the core plasma was almost the same. Calculated shrinking coefficient of runaway electrons emission after the plasma disruption was about 26 m/s according to the experimental data (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
5.
Yunus Taskesenligil Ferruh Lafzi Haydar Kilic Nurullah Saracoglu 《Journal of heterocyclic chemistry》2019,56(12):3289-3296
Pd(II)‐catalyzed C‐H arylations of 5‐aminoindole using iodobenzenes as aryl source was studied. Despite pivalamide directing group at 5‐position of the indole, the direct C2‐arylation of the indole observed in high yields and with high regioselectivity. 相似文献
6.
Haydar Kilic Omer Aydin Sinan Bayindir Nurullah Saracoglu 《Journal of heterocyclic chemistry》2016,53(6):2096-2101
Bismuth nitrate catalyzed condensation reactions of indoline with 1,2‐ and 1,3‐diketones were investigated and were reported to proceed via different reaction pathways with the involvement of one or two of the carbonyl groups. While the reaction of indoline with cyclohexane‐1,3‐dione ( 4 ) gave solely condensation product, the reaction between the acetylacetone ( 5 ) and indoline provided N‐acetyl indoline as single products on retro‐aldol process. In contrast to 1,3‐diketones, the reaction with benzil ( 17 ) was performed under difficult conditions and proceeded to give secondary products. 相似文献
7.
Saracoglu S Soylak M Peker DS Elci L dos Santos WN Lemos VA Ferreira SL 《Analytica chimica acta》2006,575(1):133-137
The present paper proposes a pre-concentration procedure for determination of lead and iron in several samples by flame atomic absorption spectrometry. In it, lead(II) and iron(III) ions are coprecipitated using the violuric acid-copper(II) system as collector. Afterwards, the precipitate is dissolved with 1 M HNO3 solution and the metal ions are determined. The optimization step was performed using factorial design involving the variables: pH, violuric acid mass (VA) and copper concentration (Cu).Using the optimized experimental conditions, the proposed procedure allows the determination these metals with detection limits of 0.18 μg L−1 for iron and 0.16 μg L−1 for lead. The effects of foreign ions on the pre-concentration procedure were also evaluated and the results demonstrated that this method could be applied for determination of iron and lead in several real samples. The proposed method was successfully applied to the analysis of seawater, urine, mineral water, soil and physiological solution samples. The concentrations of lead and iron achieved in these samples agree well with others data reported in the literature. 相似文献
8.
Multi-element determination of trace elements in urine and dialysis solutions by atomic absorption spectrometry has been investigated. Coprecipitation with samarium hydroxide was used for preconcentration of trace elements and elimination of matrix elements. To 10 ml of each sample was added 500 μl of 2 mg ml−1 samarium solutions; the pH was then adjusted to 12.2 in order to collect trace heavy metals on samarium hydroxide. The precipitate was separated by centrifugation and dissolved in 1 ml of 1 mol l−1 HNO3. Coprecipitation parameters and matrix effects are discussed. The precision, based on replicate analysis, is around 5% for the analytes, and recovery is quantitative, based on analysis of spiked samples and solutions including matrix components. The time required for the coprecipitation and determination was about 30 min. 相似文献
9.
H. W. Schramm M. Schubert-Zsilavecz A. I. Saracoglu Ch. Kratky 《Monatshefte für Chemie / Chemical Monthly》1991,122(12):1063-1073
Summary Alkylbiguanides2 a–e react with benzoin (1) at thepH of the base in different ways.1 undergoes in presence of2 a, c oxidation to benzoic acid which reacts with the bases2 a, c to yield 4-phenyl-1,3,5-triazinamines3 c, 4 c; in presence of2 b 1 is transformed to benzil, which reacts with2 b under rearrangement to yield 1-(4-oxo-5,5-diphenyl-2-imidazolin-2-yl)-3,3-dimethylguanidine (5 b). However, the cycloalkylbiguanides2 d, e, react in presence of nitrogen as well as oxygen with1 to yield piperidine-1-[N-(4,5-diphenylimidazol-2-yl)-carboxamidine] (7 d), resp. morpholine-4-[N-(4,5-diphenylimidazol-2-yl)-carboxamidine] (7 e). The structure of7 e was established by means of an X-ray structure analysis. All proton- and carbon resonances were assigned on the basis of 2-dimensional NMR data. 相似文献
10.
Synthesis of Some Novel Norbornene‐Fused Pyridazines as Potent Inhibitors of Carbonic Anhydrase and Acetylcholinesterase 下载免费PDF全文
Ramazan Kocak Esra Turan Akın Pınar Kalın Oktay Talaz Nurullah Saracoglu Arif Dastan Ilhami Gülcin Serdar Durdagi 《Journal of heterocyclic chemistry》2016,53(6):2049-2056
The reaction of benzocyclic norbornene derivatives with tetrazines provided the 1,3‐dihydropyridazine derivatives as a single product. The dihydropyridazine derivatives have been dehydrogenated with phenyliodine bis(trifluoroacetate) to yield the corresponding pyridazines in a high yield. Two stable diazines, primary product of corresponding 1,4‐dihydropyridazine, were also isolated. Structures were then determined by 1H‐NMR, and 13C‐NMR beside to elemental analyses. The novel pyridazine derivatives ( 8 , 9 ) efficiently inhibited the cytosolic human carbonic anhydrase isoenzymes I and II (hCA I and II). In addition, these novel pyridazine derivatives ( 8 , 9 ) were evaluated for their in vitro acetylcholinesterase inhibitory activity. Ligand–receptor interactions are tested using molecular docking simulations. Obtained docking scores are in good agreement with in vitro results. 相似文献