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991.
Alexander V. Zuraev Yuri V. Grigoriev Vladislav A. Budevich Oleg A. Ivashkevich 《Tetrahedron letters》2018,59(16):1583-1586
A new method for Huisgen [3+2] cycloaddition synthesis of 1,4- and 1,4,5-substituted-1H-1,2,3-triazoles was reported. The reaction was catalyzed by the product of thermolysis of copper (II) poly-5-vinyltetrazolate. Heterogeneous catalyst includes copper nanoparticles which supported on polymeric matrix. It presents recovered and recycled catalyst and the catalyzed reaction proceeds in aerobic conditions at room temperature in aqueous media. 相似文献
992.
Jonas Köhling Dr. Volodymyr Kozel Dr. Vladislav Jovanov Dr. Romana Pajkert Dr. Sergey N. Tverdomed Oleg Gridenco Malte Fugel Prof. Dr. Simon Grabowsky Prof. Dr. Gerd-Volker Röschenthaler Prof. Dr. Veit Wagner 《Chemphyschem》2019,20(5):665-671
A blue-light emitting material based on a boron complex containing heteroaromatic phosphonate ligand is synthesized and characterized. The Phospho-Fries rearrangement is used in the synthesis route of the ligand as a convenient method of introducing phosphonate groups into phenols. Structural, thermal and photophysical properties of the resulting oxazaborinin phosphonate compound have been characterized. DFT geometry optimizations were studied as well as the spatial position and symmetry of the HOMO and LUMO. Good thermal stability up to 250 °C enables vacuum deposition methods next to solution processing. Combining the work function with the optical band gap from UV-Vis measurements shows that band alignment is possible with standard contact materials. Photoluminescence reveals an emission peak at 428 nm, which is suitable for a blue light-emitter. 相似文献
993.
994.
995.
Demekhin Oleg D. Zagrebaev Aleksander D. Burov Oleg N. Kletskii Mikhail E. Pavlovich Natal’ya V. Bereznyak Elena A. Tsimbalistova Marina V. Kurbatov Sergey V. 《Chemistry of Heterocyclic Compounds》2019,55(11):1128-1130
Chemistry of Heterocyclic Compounds - A method for the synthesis of berberine 13-vinyl derivatives has been developed consisting of an initial reaction of triethyl orthoformate with CH acids in the... 相似文献
996.
Taniya Olga S. Kopchuk Dmitry S. Khasanov Albert F. Kovalev Igor S. Zyryanov Grigory V. Charushin Valery N. Chupakhin Oleg N. 《Chemistry of Heterocyclic Compounds》2019,55(6):505-507
Chemistry of Heterocyclic Compounds - Microreview focuses on the main modern synthetic approaches toward 2-azaanthracene and its derivatives. These approaches are: inverse electron-demand... 相似文献
997.
Oleg V. Bityukov Vera A. Vil George K. Sazonov Andrey S. Kirillov Nikita V. Lukashin Gennady I. Nikishin Alexander O. Terentev 《Tetrahedron letters》2019,60(13):920-924
It was discovered that the Kharasch peroxidation of barbituric acids proceeds both with a Cu-catalyst and without a metal catalyst. Despite the presence of possible thermal-initiated side oxidation pathways, α-tert-butylperoxybarbiturates were selectively prepared from substituted barbituric acids and tert-butyl hydroperoxide. 相似文献
998.
We present a new method for calculating the diffusion tensor for the systems of sorbates inside nanoporous materials at different loadings by just using transition rate constants. In addition, a user-friendly program with graphical user interface has been developed and is freely provided to be used ( https://sourceforge.net/projects/kobra/ ). It needs from the user just to provide the values of the unit cell lengths and angles, the transition rate constants for each sorbate, and any spatial constraint between these sorbates. This program is shown to be about 30 times faster than kinetic Monte Carlo method. Application of the method to the problem of diffusion of aromatics in silicalite-1 at different loadings is presented too. © 2019 Wiley Periodicals, Inc. 相似文献
999.
Oleg L. Eliseev Tatyana N. Bondarenko Sergey N. Britvin Polina P. Khodorchenko Albert L. Lapidus 《Mendeleev Communications》2018,28(3):264-266
Rhodium-catalysed hydroformylation of styrene and aliphatic olefins under biphasic conditions in the presence of watersoluble 1,4,7-triaza-9-phosphatricyclo[5.3.2.14,9]tridecane (CAP) chemoselectively affords aldehydes. Multiple catalyst reuse without loss in performance is demonstrated. 相似文献
1000.
Vyacheslav Ya. Sosnovskikh Daria A. Vetyugova Alexander V. Safrygin Oleg S. Eltsov Pavel A. Slepukhin 《Mendeleev Communications》2018,28(4):434-436
2-(Ethoxalylmethyl)chromones undergo dimerization to dichromonyl derivatives of isotetronic acid in 62–89% yields on refluxing with 2,3-diaminopyridine in ethanol for 1–2 h. 相似文献