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21.
Tetrakis‐(4‐chlorophenylthio)‐butatriene (3a) and tetrakis‐(tert‐butylthio)‐butatriene (3b) were synthesized, and their crystal structures were determined. The compound 3a is monoclinic, space group P21/c, a=6.9785(8), b=8.6803(9), c=22.884(2) Å, β=93.887(6)o, V=1383.0(3) Å3, Z=2. The compound 3b is monoclinic, space group P21/n, a=11.0615(6), b=10.8507(4), c=11.2717(6) Å, β =116.427(2)o, V=1211.5(1) Å3, Z=4. The title compounds 3a and 3b reside on an inversion center so that only half of the molecule is crystallographically unique. Both compounds are not planar. The crystal structures of 3a and 3b have cumulated double bonds. The C7–C8–C8i and C5–C6–C6i angles that show the linearity in both structures, respectively, are 176.4(3)° in 3a and 175.6(2)° in 3b. 相似文献
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Cigdem Hopa Ismail Cokay 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(2):149-154
The design and synthesis of polymeric coordination compounds of 3d transition metals are of great interest in the search for functional materials. The coordination chemistry of the copper(II) ion is of interest currently due to potential applications in the areas of molecular biology and magnetochemistry. A novel coordination polymer of CuII with bridging N,N′‐bis(2‐hydroxyphenyl)‐2,2‐dimethylpropane‐1,3‐diamine (H2L‐DM) and dicyanamide (dca) ligands, catena‐poly[[[μ2‐2,2‐dimethyl‐N,N′‐bis(2‐oxidobenzylidene)propane‐1,3‐diamine‐1:2κ6O,N,N′,O′:O,O′]dicopper(II)]‐di‐μ‐dicyanamido‐1:2′κ2N1:N5;2:1′κ2N1:N5], [Cu2(C19H20N2O2)(C2N3)2]n, has been synthesized and characterized by CHN elemental analysis, IR spectroscopy, thermal analysis and X‐ray single‐crystal diffraction analysis. Structural studies show that the CuII centres in the dimeric asymmetric unit adopt distorted square‐pyramidal geometries, as confirmed by the Addison parameter (τ) values. The chelating characteristics of the L‐DM2− ligand results in the formation of a CuII dimer with a double phenolate bridge in the asymmetric unit. In the crystal, the dimeric units are further linked to adjacent dimeric units through μ1,5‐dca bridges to produce one‐dimensional polymeric chains. 相似文献
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Cigdem Hopa Ismail Cokay 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(8):601-606
Schiff bases are considered `versatile ligands' in coordination chemistry. The design of polynuclear complexes has become of interest due to their facile preparations and varied synthetic, structural and magnetic properties. The reaction of the `ligand complex' [CuL] {H2L is 2,2′‐[propane‐1,3‐diylbis(nitrilomethanylylidene)]diphenol} with Ni(OAc)2·4H2O (OAc is acetate) in the presence of dicyanamide (dca) leads to the formation of bis(dicyanamido‐1κN1)bis(dimethyl sulfoxide)‐2κO,3κO‐bis{μ‐2,2′‐[propane‐1,3‐diylbis(nitrilomethanylylidene)]diphenolato}‐1:2κ6O,O′:O,N,N′,O′;1:3κ6O,O′:O,N,N′,O′‐dicopper(II)nickel(II), [Cu2Ni(C17H16N2O2)2(C2N3)2(C2H6OS)2]. The complex shows strong absorption bands in the frequency region 2155–2269 cm−1, which clearly proves the presence of terminal bonding dca groups. A single‐crystal X‐ray study revealed that two [CuL] units coordinate to an NiII atom through the phenolate O atoms, with double phenolate bridges between CuII and NiII atoms. Two terminal dca groups complete the distorted octahedral geometry around the central NiII atom. According to differential thermal analysis–thermogravimetric analysis (DTA–TGA), the title complex is stable up to 423 K and thermal decomposition starts with the release of two coordinated dimethyl sulfoxide molecules. Free H2L exhibits photoluminescence properties originating from intraligand (π–π*) transitions and fluorescence quenching is observed on complexation of H2L with CuII. 相似文献
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Polymers with alternating anthracene and phenylene building blocks linked by ethynylene and/or vinylene units: Studying structure‐properties‐relationships
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Sameh Boudiba Aleš Růžička Christoph Ulbricht Sandra Enengl Christina Enengl Jacek Gasiorowski Cigdem Yumusak Veronika Pokorná Drahomír Výprachtický Kurt Hingerl Dietrich R. T. Zahn Francesca Tinti Nadia Camaioni Sabrina Bouguessa Abdelkrim Gouasmia Věra Cimrová Daniel Ayuk Mbi Egbe 《Journal of polymer science. Part A, Polymer chemistry》2017,55(1):129-143
Four conjugated polymers ( P1 – P4 ) consisting of alternating anthracene‐9,10‐diyl and 1,4‐phenylene building blocks connected via ethynylene as well as vinylene ( P1 and P2 ), ethynylene‐only ( P3 ), and vinylene‐only ( P4 ) moieties, respectively, were synthesized and studied. The phenylene units in all four polymers bear 2‐ethylhexyloxy side‐chains to promote good solubility. The three polymers with vinylene units ( P1 , P2 , and P4 ) were prepared using the Horner–Wadsworth–Emmons reaction. For the synthesis of the arylene‐ethynylene polymer P3, the palladium‐catalyzed Sonogashira cross‐coupling reaction was used. The polymers were characterized by NMR, Fourier transform infrared spectroscopy, and Raman spectroscopy. Photophysical, absorption and photoluminescence, and electrochemical properties were studied. Spectroscopic ellipsometry measurements were performed to gain more insight on the optical properties. In addition, the transport properties were investigated using admittance spectroscopy. The bulk hole mobility and its dependence on the electric field were evaluated for P1 and P2 . © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 129–143 相似文献
26.
de Lara LS Michelon MF Metin CO Nguyen QP Miranda CR 《The Journal of chemical physics》2012,136(16):164702
We have used molecular dynamics simulations to calculate the interfacial tension of hydroxylated SiO(2) nanoparticles under different temperatures and solutions (helium and brine with monovalent and divalent salts). In order to benchmark the atomistic model, quartz SiO(2) interfacial tension was measured based on inverse gas chromatography under He atmosphere. The experimental interfacial tension values for quartz were found between 0.512 and 0.617 N/m. Our calculated results for the interfacial tension of silica nanoparticles within helium atmosphere was 0.676 N/m, which is higher than the value found for the system containing He∕α-quartz (0.478 N/m), but it is similar to the one found for amorphous silica surface. We have also studied the interfacial tension of the nanoparticles in electrolyte aqueous solution for different types and salts concentrations (NaCl, CaCl(2), and MgCl(2)). Our calculations indicate that adsorption properties and salt solutions greatly influence the interfacial tension in an order of CaCl(2) > MgCl(2) > NaCl. This effect is due to the difference in distribution of ions in solution, which modifies the hydration and electrostatic potential of those ions near the nanoparticle. 相似文献
27.
Palladium-catalyzed hydroarylations and additional domino reactions of aza-bicyclic and tricyclic norbornene derivatives were investigated and a series of new epibatidine analogues were synthesized. 相似文献
28.
We consider a decentralized, pull-type manufacturing system with each stage having its own input and output stock keeping activities. Material handling between stages is carried out according to a fixed quantity, non-constant withdrawal cycle. We approximate the system behavior using a two-node decomposition approach, which decomposes the system into smaller subsystems. The analysis of two-node subsystems is achieved using a matrix-recursive approach due to phase-type modeling of certain random variables. Our solution algorithm resolved a major difficulty (due to batch transfers) in the analytical approach to study multi-stage manufacturing systems. We also discuss system behavior and suggest several rules-of-thumb to improve system performance. 相似文献
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Cigdem Sayil Semih Kurban Cemil Ibis 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1855-1867
Abstract New N,S-disubstituted naphthoquinones were synthesized by reactions of S- and N-nucleophiles with 2,3-dichloro-1,4-naphthoquinone. 2-(Hexadecylthio)-3-(phenylamino)-naphthalene-1,4-dione 5a was synthesized by reaction of 2-chloro-3-(phenylamino)-naphthalene-1,4-dione 3a with hexadecanethiol 4a. The structures of the new synthesized naphthoquinone derivatives were determined by micro analyses and spectroscopic methods (FT-IR, 1H NMR, 13C NMR, MS, and UV/Vis.). Photo- and electrochemical properties of selected compounds were investigated by using fluorescence spectroscopy and the cyclovoltammetry method. 相似文献
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Tayfun Yilmaz Perihan Unak Fazilet Zumrut Biber Muftuler Emin Ilker Medine Serhan Sakarya Cigdem Acar Ichedef Turan Unak 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):1395-1404
Diethylstilbestrol (DES) is a synthetic non-steroidal estrogen, pharmacologic effects of which resemble natural estrons; today it is being used to treat some types of postmenopausal breast cancer and advanced prostate cancer. The aim of current study is conjugation of glucuronic acid (G) to DES and to evaluate radiopharmaceutical potential of this estrogen glucuronide derivative (DESG) which is specific to β glucuronidase enzyme consisting tumor cells. Taking into consideration the compatibility to the chemical structures of the synthesized product, 131I and 125I were chosen as the appropriate radionuclides and DESG was labeled with these radionuclides utilizing iodogen method. The radiochemical yields of 125/131I-DESG were over 90 % according to thin layer radio chromatography method. The biodistribution of 131I-DESG in healthy female Wistar Albino rats has been investigated and the range of the breast/blood and breast/muscle ratios were approximately 2 and 13 in 240 min for ER unsaturated studies. Effects of the radioiodinated DES and DESG on the cells were examined using MCF-7, A-549, Caco-2 cell lines. 125I-DESG has higher incorporation percentages than 125I-DES on MCF-7 cells. The radioiodinated DESG has the desired radiopharmaceutical properties which could be candidate radiopharmaceuticals for diagnosis and especially radionuclide therapy of breast tumors. 相似文献