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11.
Katritzky AR Akhmedov NG Abdel-Fattah AA Wang M Rostek CJ Maender OW 《Magnetic resonance in chemistry : MRC》2004,42(5):424-435
Nucleophilic addition of alkyl- and benzylthiols to benzoquinone diimine (1) gave the corresponding 3-alkylthio- or 3-benzylthio-1,4-phenylenediamines (2-5). However, addition of aryl- or heteroarylthiols to 1 formed 2-arylthio- or 2-heteroarylthio-1,4-phenylenediamines (6-14). The structures of 2-14, obtained in 55-91% yields, were confirmed in CDCl3 or DMSO-d6 solution using 1D (NOE difference, coupled 13C NMR spectra, APT and DEPT) and 2D NMR techniques [DQCOSY, NOESY, HETCOR and heteronuclear multiple bond coherence (HMBC)] that resulted in unambiguous proton and carbon NMR resonance assignments. The substituent-induced 13C NMR chemical shift differences were calculated in 2-14 relative to carbon atoms in the model compound N1-(1,3-dimethylbutyl)-N4-phenyl-1,4-phenylenediamine (DMBPPD) (15) (a reduced form of benzoquinone diimine). 相似文献
12.
Katritzky AR Akhmedov NG Wang M Rostek CJ Steel PJ 《Magnetic resonance in chemistry : MRC》2004,42(7):648-658
The 1H and 13C NMR spectra of compounds 1-11 and 16-22 in CDCl3 and DMSO-d6 solutions allowed structural assignment to regioisomers 1/5 and 2/6 and their regioselective cyclization products 16-18 utilizing one- and two-dimensional NMR techniques (APT, DEPT, NOE difference, COSY, NOESY, HETCOR and gHMQC, gHMBC). Temperature-dependent 1H NMR spectra of 8-anilino-5-(4-methyl-2-pentyl)-2,3-dihydro-1,5-benzothiazepin-4(5H)-one (18) indicated a free energy of activation (deltaG++) of ca 17 kcal mol(-1) for interconversion between rotamers. The 1H and 13C NMR spectra of 20 and 22 containing two chiral centers exhibit duplication of several signals, indicating the existence of two diastereomeric forms. The structure of 4 was unambiguously confirmed by x-ray crystallography. 相似文献
13.
A. I. Akhmedov N. A. Talyshova A. M. Gasanova 《Russian Journal of Applied Chemistry》2013,86(8):1314-1316
Cooligomers of 1-hexene with dicyclopentadiene were synthesized. Depending on the cooligomerization conditions, cooligomers with the molecular weight of 1000–4000, containing 10–20% dicyclopentadiene units, were obtained in a 76–92% yield. Aluminum chloride was used as the cooligomerization catalyst. The cooligomers synthesized were tested as components to M-6 and I-12A petroleum oils with the view of increasing their viscosity. The use of 25–40% cooligomer in these oils allows preparation of base oils with the viscosity index of 93–126. The resultant compounded oil possesses anticorrosive properties due to the presence of the dicyclopentadiene units in the cooligomer. 相似文献
14.
15.
Yu Zhang Dr. Novruz G. Akhmedov Prof. Jeffrey L. Petersen Prof. Carsten Milsmann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(12):3042-3052
Luminescent seven-coordinated zirconium and hafnium complexes bearing three mono-anionic 2,2′-pyridylpyrrolide ligands and one chloride were synthesized. Solid-state structures and the dynamic behaviors in solution were probed by X-ray crystallography and variable temperature 1H NMR experiments, respectively. Absorption spectroscopy and time-dependent density functional theory (TD-DFT) calculations supported a hybrid of ligand-to-metal charge transfer (LMCT)/ligand-to-ligand charge transfer (LLCT) for the visible light absorption band. The complexes (MePMPMe)3MCl (M=Zr, Hf, MePMPMe=3,5-dimethyl-2-(2-pyridyl)pyrrolide) are emissive in solution at room temperature upon irradiation with visible light due to a combination of phosphorescence and fluorescence characterized by excited state lifetimes in the μs and low to sub-ns timescale, respectively. Electrochemical experiments revealed that the zirconium complex possesses a reversible redox event under highly reducing condition (−2.29 V vs. Fc+/0). 相似文献
16.
Rabadanov K. Sh. Gafurov M. M. Kubataev Z. Yu. Amirov A. M. Akhmedov M. A. Shabanov N. S. Ataev M. B. 《Russian Journal of Electrochemistry》2019,55(6):573-578
Russian Journal of Electrochemistry - Composite solid electrolytes are synthesized on the basis of the eutectic nitrate mixture of 0.42LiNO3–0.58KNO3 doped by aluminum oxide nanosized powder.... 相似文献
17.
Aliev A. R. Akhmedov I. R. Kakagasanov M. G. Aliev Z. A. 《Physics of the Solid State》2020,62(6):998-1010
Physics of the Solid State - Processes of molecular relaxation in Li2SO4, Na2SO4, and K2SO4 sulfates; Li2CO3, Na2CO3, and K2CO3 carbonates; NaClO4 and KClO4 perchlorates; and Ca(NO3)2, Sr(NO3)2,... 相似文献
18.
Sh. M. Alekperova I. A. Akhmedov G. S. Gadzhieva Kh. D. Dzhalilova 《Physics of the Solid State》2007,49(3):512-515
Isotropic giant negative magnetoresistance (from ?42 to ?52%) in magnetic fields of 6–9 kOe is revealed for the first time when studying kinetic phenomena and the magnetoresistive effect in silver sulfoselenide (n-Ag4SSe) in the vicinity of a first-order phase transition. The electron transport and the magnetoresistive effect in n-Ag4SSe are studied for the first time. 相似文献
19.
A. V. Vorogushin M. D. Reshetova N. G. Akhmedov Yu. A. Ustynyuk I. L. Eremenko S. E. Nefedov A. I. Zinin 《Russian Chemical Bulletin》1998,47(4):699-703
The reaction of Cr(CO)6 with 7,7-dichloro-3,4-benzobicyclo[4.1.0]heptane gave the correspondingexo- andendo-chromium tricarbonyl complexes in a ratio of 4.5:1. The structures of the resulting compounds were established by NMR spectroscopy,
mass spectrometry, and X-ray structural analysis. Reduction of dichlorobenzobicycloheptane and its chromium tricarbonyl complexes
with LiAlH4 affordedexo- andendo-7-chloro-3,4-benzobicyclo[4.1.0]heptanes in a 3.5:1 ratio.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 720–724, April, 1998. 相似文献
20.