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81.
82.
Jing-An Zhang Mei Pan Jian-Yong Zhang Hai-Ke Zhang Zhi-Jin Fan Bei-Sheng Kang Cheng-Yong Su 《Polyhedron》2009
Three silver(I) complexes of the asymmetric tridentate ligand 8-((pyridin-3-yl)methylthio)quinoline (TQMP3), namely [Ag2(TQMP3)2(NO3)2] (1), [Ag2(TQMP3)2(CF3CO2)2] (2) and {[Ag2(TQMP3)2](CF3SO3)2(H2O)}n (3), have been prepared by the method of layering and diffusing of diethyl ether. The structures of the complexes have been identified by elemental analysis (EA), infrared spectra (IR) and single-crystal diffraction, and are composed of discrete binuclear rings in complexes 1 and 2, with π–π interactions or H-bonds further extending the structures into 2D nets, while in complex 3, Ag?Ag interactions between the rings result in a 1D polymer chain. The antibacterial, antifungal and pesticide activities of the three complexes were tested. 相似文献
83.
MEN Yican ZHANG Jiqian ZHOU Lishan LI Junqiu LIU Jun LI Juan QU Hongmei 《高等学校化学研究》2016,32(4):621-624
A series of quinoline derivatives was obtained in high yields by an efficient one-pot reaction of substituted o-diiodobenzenes with azazirconacyclopentadienes, which were conveniently prepared from one internal alkyne and one nitrile mediated by zirconocene. This proposed synthetic method provides a feasible way to the synthesis of large N-heterocyclic π-conjugated molecules. 相似文献
84.
A gold-catalyzed three-component coupling reaction (A3 reaction) was developed as an efficient approach for the synthesis of challenging 2,4-disubstituted quinoline derivatives. Compared to previously reported Cu/Au bi-catalyst system, this protocol enables achieving A3 reaction only in the presence of triazole-gold catalyst. Notably, 4-alkyl substituted or 2-alkyl substituted quinoline derivatives were obtained with good yields, which highlighted the unique advantage of this new strategy. 相似文献
85.
Mohammad Soltani Benjamin Siu E. Alan Salter Andrzej Wierzbicki Kevin N. West James H. Davis 《Tetrahedron letters》2017,58(49):4628-4631
Seven new ionic liquids have been prepared which contain tetraarylphosphonium cations in which one of the aromatic groups is a quinoline ring. These compounds, which differ from each other in the point of attachment of the quinoline to the phosphorous core, were evaluated by DSC and TGA, then screened for thermal stability for 96?h at temperatures up to 300?°C. The observed thermal stabilities of the salts were found to be sensitive to the position of quinoline ring substitution, and correlated well with computed homolytic bond dissociation energies of the quinoline-P bonds. 相似文献
86.
In this study, the optical and dielectrical properties of a novel series of quinoline azodyes (5-(4′-derivatives phenyl azo)-8-hydroxy-7-quinolinecarboxaldehyde) (AQL1–AQL5) were investigated and the obtained results were analyzed. The X-ray diffraction (XRD) patterns of AQLn show that the materials in the powder form are a mixture of amorphous and crystalline structure, while the thermally deposited thin films are completely amorphous. The optical constants such as the refractive index, n, the absorption index, k and the absorption coefficient, α, were determined using spectrophotometric measurements of transmittance (T) and reflectance (R) in the wavelength range 200–2500 nm. According to the single oscillator model (SOM), some related parameters such as oscillation energy (Eo), the dispersion energy (Ed), the optical dielectric constant (ε∞), the lattice dielectric constant (εL) and the ratio of free carrier concentration to its effective mass (N/m*) are estimated. The emission spectra of azo quinoline ligands (AQLn) exhibit dual fluorescence peaks in the region 512–580 nm. This finding reveals the formation of two stoichiometric hydrogen-bonding in the ground and excited state. The dielectrical properties and alternating current conductivity (σAC) are investigated in temperature range 298–483 K and frequency range 0.1–100 KHz. 相似文献
87.
A. A. A. Boraei 《Monatshefte für Chemie / Chemical Monthly》1994,125(8-9):869-876
Summary The deprotonation and acid ionization constants of some quinoline derivatives in aqueous organic solvents were determined. The organic solvents used include methanol and ethanol as amphiprotic solvents andDMF andDMSO as dipolar aprotic solvents. The obtainedpK
1 andpK
2 values are discussed with respect to the nature and the amount of the organic component. The high stabilization of the non-protonated form by dispersion forces and of the proton by its interaction with the solvent are the main factors responsible for the increase in the ionization constants of the protonated forms of the quinolines under investigation. On the other hand, H-bonding interactions (in addition to the electrostatic effect) seem to play the major role in determining the second acid-base equilibrium of 8-hydroxyquinoline. The deprotonation constants of the examined quinolines are correlated with their experimentally determined lone-pair ionization potential values.
Lösungsmitteleffekte auf die Ionisationskonstanten einiger Chinolinderivate
Zusammenfassung Die Deprotonierungs- und Ionisationskonstanten einiger Chinolinderivate wurden in wäßrigen organischen Medien, darunter Methanol und Ethanol als amphiprotische undDMF undDMSO als dipolare aprotische Lösungsmittel, bestimmt. Die gemessenenpK 1- undpK 2-Werte werden im Hinblick auf die Art und Menge der organische Komponente diskutiert. Die hohe Stabilisierung der nichtprotonierten Form durch Dispersionskräfte und des Protons durch Wechselwirkungen mit dem Lösungsmittel sind die wesentlichen Faktoren, die für den Anstieg der Ionisationskonstanten der protonierten Formen der untersuchten Chinoline verantwortlich sind. Andererseits scheinen Wasserstoffbrückenbindungen — zusätzlich zum elektrostatischen Effekt — das zweite Säure-Basen-Gleichgewicht von 8-Hydroxychinolin entscheidend zu beeinflussen. Die Deprotonierungskonstanten aller untersuchten Chinoline werden mit ihren experimentell bestimmtenlone-pair-Ionisationspotentialen korreliert.相似文献
88.
Leyla Yurttaş Aslıhan Kubilay Asaf Evrim Evren İpek Kısacık Hülya Karaca Gençer 《Phosphorus, sulfur, and silicon and the related elements》2020,195(9):767-773
AbstractSome new 3,4,5-trisubstituted 1,2,4-triazole derivatives were synthesized and studied for their antimicrobial activity. The lead compounds were obtained starting from 8-hydroxyquinoline and ethyl 2-chloroacetate. The obtained ester compound (1) first reacted with hydrazine hydrate (2) then with phenyl isothiocyanate (3). Ring closure by KOH led to 3-mercapto-1,2,4-triazole derivative (4). Lastly, it reacted with 2-chloro-N-(substituted (benzo)/thiazole)acetamide derivatives to obtain the final compounds (5a–j). The structural elucidation of the compounds was performed by 1H NMR and 13C NMR spectroscopy and high resolution mass spectrometry techniques and elemental analysis. The synthesized compounds were investigated for their antimicrobial activities against seven bacteria and four fungi. As a result of the activity studies, it was observed that compounds N-(6-nitrobenzothiazol-2-yl)-2-[[4-phenyl-5-((quinolin-8-yloxy)methyl)-4H-1,2,4-triazol-3-yl]thio]acetamide (5a) and N-(6-fluorobenzothiazol-2-yl)-2-[[4-phenyl-5-((quinolin-8-yloxy)methyl)-4H-1,2,4-triazol-3-yl]thio]acetamide (5d) were the most active molecules. Also, the antifungal activity of the compounds was found to be higher than their antibacterial activity although lower than the standard drug’s potential. Additionally, the physicochemical properties of the compounds were calculated which were evaluated to be at a suitable range for oral administration. 相似文献
89.
EEDQ and EEDI generated in situ by the reaction of quinoline and isoquinoline with diethyl pyrocarbonate was treated with alkylating reagents having an activated carbon such as diethyl malonate, ethyl acetoacetate etc. in the presence of 0.5 equiv of LiCl in acetonitrile to provide the corresponding alkyl dihydroquinolines and alkyl dihydroisoquinolines in high yields. 相似文献
90.
Antimony trichloride (SbCl3) was found to be an efficient catalyst for the inverse electron demand imino Diels-Alder reactions of in situ generated N-benzylidenes with 3,4-dihydro-2H-pyran and 2,3-dihydrofuran to afford pyrano and furano[3,2-c]quinolines in excellent yields. 相似文献