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991.
Tarasova O. A. Nedolya N. A. Albanov A. I. Trofimov B. A. 《Russian Journal of Organic Chemistry》2017,53(2):305-308
Russian Journal of Organic Chemistry - N-Alkylidene-1-(propargylsulfanyl)-2-(1H-pyrrol-1-yl)buta-1,3-dien-1-amines at treatment by a superbasic system t-BuONa–THF–DMSO under standard... 相似文献
992.
993.
I.?A.?Os’kinaEmail author А.?Ya.?Tikhonov 《Russian Journal of Organic Chemistry》2017,53(8):1239-1242
Reaction of 2-(hydroxyamino)-1-R-propan-1-one oximes with furfural in methanol afforded the corresponding α-furylnitrones. The cyclization of α-furylnitrones in alkaline medium results in the formation of 5-aryl(hetaryl)-2-(furan-2-yl)-1H-imidazol-1-oles. 相似文献
994.
Bidusenko I. A. Cherimichkina N. A. Schmidt E. Yu. Trofimov B. A. 《Russian Journal of Organic Chemistry》2017,53(3):470-471
Russian Journal of Organic Chemistry - Chalcone reacted with acetylene in a suspension of KOH in DMSO at 90°C (30 min) to give 36% of 2-methyl-3,5-diphenylfuran. 相似文献
995.
I. A. Novakov L. L. Brunilina A. A. Vernigora I. A. Kirillov A. S. Mkrtchyan M. B. Navrotskii D. S. Sheikin A. S. Yablokov E. A. Ruchko V. V. Kachala 《Russian Journal of Organic Chemistry》2017,53(12):1844-1850
The aminolysis of 6-[1-(2,6-difluorophenyl)cyclopropyl]-5-methyl-2-(nitroamino)pyrimidin-4(3H)-one with various amines in butan-1-ol and under solvent-free conditions is successful when the amino group in the reagent is sterically unshielded and the reaction medium is characterized by a high dielectric permittivity. Reactions of the title compound with sterically shielded amines are accompanied by alcoholysis where the amine acts as a base catalyst. 相似文献
996.
M.?V.?Markova L.?N.?Sobenina I.?A.?Ushakov A.?V.?Ivanov B.?A.?TrofimovEmail author 《Russian Journal of Organic Chemistry》2017,53(2):184-191
Aminomethylation of 2-methyl(aryl)-, 2-aryl-3-alkylpyrroles, 4,5,6,7-tetrahydroindole and its 1-vinyl- and 1-benzyl-substituted derivatives with a mixture of 5% water-ethanol solution of formaldehyde and cyclic amine (pyrrolidine, piperazine, and morpholine) without catalyst at room temperature leads to the formation of the corresponding 2-aminomethylpyrroles and 2-aminomethyl-4,5,6,7-tetrahydroindoles in up to 92% yields. In reaction of 1-vinyl-4,5,6,7-tetrahydroindole with formaldehyde water solution and piperazine in a 60% yield 1,4-bis(1-vinyl-4,5,6,7-tetrahydroindol-2-yl)piperazine was obtained, a promising bifunctional monomer and a building block for the synthesis of new indole derivatives, in particular, of biologically active polymers. In the reaction of 2-methylpyrrole and 4,5,6,7-tetrahydroindole with formaldehyde and morpholine along with the С2-aminomethylation the 1-hydroxymethylation of the pyrrole ring was observed. 相似文献
997.
N.?O.?YaroshEmail author L.?V.?Zhilitskaya L.?G.?Shagun I.?A.?Dorofeev L.?I.?Larina 《Russian Journal of Organic Chemistry》2017,53(3):413-417
2-Methyl-1,3-bis[(1-methylsilolan-1-yl)methyl]-1H-imidazolium triiodide, 1,3-bis{[dimethyl-(phenyl)silyl]methyl}-2-methyl-1H-imidazolium iodide and triiodide, and cyclic 3,3,5,5,10-pentamethyl-4-oxa-7-aza-1-azonia-3,5-disilabicyclo[5.2.1]deca-1(10),8-diene iodide were synthesized by solvent-free reactions of 2-methyl-1H-imidazole with 1-(iodomethyl)-1-methylsilolane, (iodomethyl)(dimethyl)phenylsilane, and ethynyl(iodomethyl)(dimethyl)silanes, respectively, in the absence of base catalyst. 相似文献
998.
Marianna I. Triantou Petroula A. Tarantili 《Journal of Thermal Analysis and Calorimetry》2017,129(2):743-754
In the present research, the isothermal and non-isothermal crystallization of polypropylene (PP) phase in PP-rich poly(acrylonitrile–butadiene–styrene)/polypropylene (ABS/PP) blends was studied. The effect of nanofillers’ incorporation and specialty of organically modified montmorillonite (OMMT) and graphene, into the prepared blends on the isothermal and non-isothermal crystallization of PP phase, were investigated. Moreover, kinetic study of their isothermal crystallization process was carried out, by applying the Avrami equation. The addition of ABS to the PP matrix increased the crystallization rate of PP at 130 °C. The incorporation of OMMT in pure PP accelerated slightly the crystallization process, whereas in ABS/PP blends, it seemed to retard crystallization, due to interactions between ABS phase and organoclay. The incorporation of graphene in pure PP accelerated impressively its isothermal crystallization, while the addition of ABS in graphene/PP nanocomposite slowed down the crystallization rate of PP. The effect of ABS and nanofillers, separately or in combination, on the crystallization of PP phase was reflected on the kinetic parameters of the Avrami equation. Regarding the non-isothermal crystallization, ABS/PP blends presented higher crystallization temperature (T c) compared to pure PP. The organoclay reinforcement did not have any obvious effect on this temperature, whereas graphene caused significant increase, acting as nucleating agent. The presence of ABS to PP increased the concentration of the β-crystalline phase, reaching its maximum value at 30 mass% ABS content. The organoclay decreased the β-PP in ABS/PP blends, whereas graphene eliminated it. 相似文献
999.
D. I. Arkhipov N. P. Bobrysheva E. L. Dzidziguri M. G. Osmolowsky O. M. Osmolovskaya 《Journal of Thermal Analysis and Calorimetry》2017,127(1):71-78
Melt modification is a method commonly used when enhancing mechanical and microstructural properties of various alloys. The addition of heterogeneous nucleation sites generally refines the given microstructure and enhances the toughness of the material. Ferroalloys based on high-melting elements require a longer incubation time in the melt which makes them liable candidates for modification agents. A research on the effect of melt modification was conducted on an indefinite chill cast iron alloy commonly used for working layers in rolls. The goal of the research was to determine the effect of ferrovanadium and ferrotungsten melt treatment with the use of thermal analysis along with thermodynamic modelling using the CALPHAD approach. The results show a decrease in the measured liquidus temperature of the modified alloy along with a possible second eutectic reaction hidden inside the main graphite/cementite eutectic reaction. Scanning electron microscopy revealed small and evenly distributed MC type carbides rich in V with W and other carbide-forming elements. The results presented in this work enable a better understanding of the impact melt modification has on the development of microstructure and subsequently the improvement in mechanical properties of the alloy. 相似文献
1000.
Offor P. O. Nwanya Assumpta C. Omah A. D. Daniel-Mkpume C. C. Maaza Malik Okorie B. A. Ezema Fabian I. 《Journal of Solid State Electrochemistry》2017,21(9):2687-2697
Journal of Solid State Electrochemistry - Zinc sulphide thin films were deposited by chemical spray pyrolysis technique. The films were deposited at substrate temperatures of 300, 350 and... 相似文献