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141.
Synthesis of palladium complexes derived from imidazolidin‐2‐ylidene ligands and used for catalytic amination reactions 下载免费PDF全文
Emine Özge Karaca Nevin Gürbüz Onur Şahin Orhan Büyükgüngör İsmail Özdemir 《应用有机金属化学》2016,30(12):1050-1055
N‐Aryl amination and the Buchwald–Hartwig reaction are of great synthetic and industrial interest and scientists accept their usefulness and versatility for obtaining arylamines. In this study Ag–N‐heterocyclic carbene complexes were used as transmetallation reagents for the synthesis of Pd–N‐heterocyclic carbene complexes. The new Pd–N‐heterocyclic carbene complexes were characterized using elemental analysis and 1H NMR, 13C NMR and infrared spectroscopies. The crystal structure of one, namely dichlorobis[1,3‐bis(2‐methylbenzyl)imidazolidin‐2‐yliden]palladium(II), is presented. The activity of the Pd(II) complexes in the coupling reaction of anilines or amines with bromobenzene was investigated. These complexes exhibited high catalytic activities in the direct synthesis of triarylamines and secondary amines in a single step. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
142.
Ozlem Usluer Sermet Koyuncu Serafettin Demic René A. J. Janssen 《Journal of Polymer Science.Polymer Physics》2011,49(5):333-341
A novel electroactive spirocyclododecylfluorene monomer named 2,7‐bis(carbazol‐9‐yl)‐9,9′‐spiro[cyclododecane‐1,9′‐fluorene] (SFC) was synthesized and electrochemically polymerized to give a very stable multi‐electrochromic polymer (poly‐SFC). Two separate oxidation processes were observed for both SFC monomer and poly‐SFC that carries two carbazole units. The polymeric film of poly‐SFC was coated onto ITO/glass surface, and it shows different colors (transparent, yellowish green, green, and dark green) upon stepwise oxidations. An electrochromic device based on poly‐SFC was assembled in the sandwich cell configuration of ITO/poly‐SFC//gel electrolyte//PEDOT/ITO. Poly‐SFC exhibits 90% of transparency at neutral state and a high contrast ratio (ΔT = 58% at 800 nm). This device constructed from it represents a response time of about 1 s, high coloration efficiency (1377 cm2 C–1) and retained its performance by 96.4% even after 1000 cycles. Exhibiting high transparency at neutral state, reversible redox behavior, resistance to overoxidation, and especially high contrast ratio at near IR region can make poly‐SFC be useful and promising candidate for electrochromic applications despite having a relatively slow response time. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2010 相似文献
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Serpil Demir Yasemin Gökçe Nazan Kaloğlu Jean‐Baptiste Sortais Christophe Darcel İsmail Özdemir 《应用有机金属化学》2013,27(8):459-464
A series of new piano‐stool iron(II) complexes comprising N‐heterocyclic carbene ligands [Fe(Cp)(CO)2(NHC)]I (NHC = 1,3‐disubstituted imidazolidin‐2‐ylidene) have been synthesized and analyzed by 1H NMR, 13C NMR, IR, elemental analysis and mass spectrometric techniques. These compounds were easily prepared from the reaction of disubstituted imidazolidin‐2‐ylidene with [FeI(Cp)(CO)2] in toluene at room temperature. These complexes were tested in the catalytic hydrosilylation reaction of aldehydes and ketones with phenylsilane in solvent‐free conditions. After a basic hydrolysis step, the corresponding alcohols were obtained in good yields. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
146.
?smail Aslan 《Applied mathematics and computation》2011,217(20):8134-8139
In this paper, we show the applicability of the first integral method, which is based on the ring theory of commutative algebra, to the regularized long-wave Burgers equation and the Gilson-Pickering equation under a parameter condition. Our method provides polynomial first integrals for autonomous planar systems. Through the established first integrals, exact traveling wave solutions are derived in a concise manner. 相似文献
147.
In this study, an artificial neural network (ANNs) for the prediction of unsteady heat transfer in a rectangular duct was
studied. The ANNs has been applied for the unsteady heat transfer in a rectangular duct. An experimental study has been carried
out to investigate the axial variation of inlet temperature and the impact of inlet frequency on decay indices in the thermal
entrance region of a parallel plate channel. The investigation was conducted with laminar forced flows for Reynolds numbers
ranging from 1,120 to 2,200 while the inlet heat input frequency varied from 0.02 to 0.24 Hz. The results revealed that the
ANNs can be used for modeling unsteady heat transfer in the duct. The accuracy between experimental and ANNs approach results
was achieved with a mean absolute relative error less than 39%. 相似文献
148.
The present study is mainly related to finding out spin-Hamiltonian parameters of Cu2+-doped potassium metabisulfite [K2S2O5] single crystals using electron paramagnetic resonance (EPR) technique which has been applied in the temperature range from 297 to 113 K for single and powder crystals of the title compound. The existence of two complexes and two Cu2+ sites for each complex was concluded from the angular variation of the EPR spectra. Having constructed the g and the hyperfine tensors, the spin-Hamiltonian parameters have been obtained for these two complexes. Using these parameters, the covalency parameter (α 2), mixing coefficients (α and β) and Fermi contact term (K) have been calculated. 相似文献
149.
Cemil İbiş Nihal Yilmaz H. Özlem Ataseven 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1897-1906
Compounds 3a–k were obtained from the reactions of compounds 1a–k with homopiperazine (2) in CH 2 Cl 2 . Compounds 1a–b, 1d–f, and 1h–l gave compounds 5a–b, 5d–f, and 5h–l with 2-methylpiperazine (4) in dichloromethane. Compounds 7c and 9c were obtained from the reactions of compound 1c with 4-ethoxycarbonyl piperazine (6) and 4-piperidinol (8) in CH 2 Cl 2 . Compounds 1a and 1f gave compounds 11a and 11f with 4-methylpiperazine (10), and compound 13f was obtained from the reactions of compound 1f with 4-methylpiperidine (12) in CH 2 Cl 2 . 相似文献
150.
Cemil İbiş F. Serpil Göksel Gökşin Aydınlı 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):777-783
Reaction of 2-nitropentachlorobutadiene with thiols and amines gave new N,S- and S,S-substituted nitrodiene compounds is discussed. 相似文献