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1.
L. P. Glushko T. M. Malinovskaya M. S. Malinovskii M. M. Kremlev N. I. Pokhodenko T. A. Zyablikova N. A. Zhikhareva 《Chemistry of Heterocyclic Compounds》1974,10(5):513-515
N,N-Diethylcarbamoyl-4,5-epoxy-2-hexenoic acid reacts with ketones in the presence of anhydrous FeCl3 to give 2,2,4-trialkyl-5-[2-N,N-diethylcarbamoyl(vinylene)]-1,3-dioxolane. 2,2,4-Trimethyl-5-(1-propenyl-3-hydroxy)-1,3-dioxolane is formed in the reduction of 2,2,4-trimethyl-5-[2-carbethoxy(vinylene)]-1,3-dioxolane withlithium aluminum hydride. 相似文献
2.
A. N. Kremlev 《Numerical Analysis and Applications》2017,10(3):207-223
An exact analytical solution to the eikonal equation for a plane wave refracted on a boundary comprising both convex and concave obtuse angles has been built. Under the convex angle summit the solution has a line of discontinuity in the ray vector field and in the first derivatives of the first arrival times, and under the concave angle it has a cone of waves diffracted on this angle. This cone corresponds to the Keller diffraction cone in the geometric diffraction theory. The relation between the eikonal equation and the resultant Hamilton–Jacoby equation for arrival times of downward waves and the ray parameter conservation equation is investigated. Solutions to these equations coincide for pre-critical incidence angles and differ for super-critical angles. It is shown that the arrival times of maximum amplitude waves, which are of the greatest practical interest, coincide with the times calculated from the ray parameter field for the ray parameter conservation equation. The numerical algorithm proposed for calculation of these times can be used for arbitrary speed models. 相似文献
3.
M. S. Rovinskii V. G. Dolyuk V. B. Zhukhovitskii V. G. Shtamburg M. M. Kremlev 《Chemistry of Heterocyclic Compounds》1977,13(6):667-668
Arenesulfonamides are split out in the reaction of N-(arylsulfonyl)arylglyoxylamides with o-phenylenediamine to give 3-aryl-2-quinoxalones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 819–820, June, 1977. 相似文献
4.
We obtain a complete classification of all the possible values of the signature of the Ricci curvature of left-invariant Riemannian
metrics on four-dimensional nonunimodular Lie groups. 相似文献
5.
Wieland Tyrra Dieter Naumann Sigrid Buslei Mikhail M. Kremlev 《Journal of fluorine chemistry》2007,128(7):813-817
A temperature range of −18 °C to room temperature was found to be effective for selective fluoride-mediated cross-coupling reactions of trimethyl(perfluoroalkyl)silanes, Me3SiCF3 and Me3SiC2F5, and alkyl halides, RX (X = Br, I) in the absence of any catalyst. 相似文献
6.
Kremlev M. M. Mushta A. I. Moklyarchuk L. I. 《Russian Journal of Organic Chemistry》2003,39(8):1125-1129
Phenols containing in the para-position of the benzene ring substituents of various electronic character add to 1,1-difluorodichloroethene in acetone in the presence of potassium hydroxide. A similar reaction with 1,2-di(fluorochloro)ethene occurs only in DMF or N,N-dimethylacetamide and is followed by hydrogen chloride elimination. Phenols with electron-donor substituents add to trifluorochloroethene in acetone in the presence of potassium hydroxide, the reaction of phenols with electron-acceptor substituents requires DMF as solvent. 相似文献
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Mikhail M. Kremlev Wieland Tyrra Aleksej I. Mushta Yurii L. Yagupolskii 《Journal of fluorine chemistry》2010,131(2):212-4521
Trifluoromethylcopper and pentafluoroethylcopper are prepared conveniently via the reaction of the solid complex Zn(CF3)Br·2DMF with copper(I) bromide in N,N-dimethylformamide. The reactions of both copper species with 2,4-dinitrochlorobenzene, 4-iodonitrobenzene, 4-nitrobenzyl iodide, 4-bromobenzoic acid ethyl ester, 4-iodobenzoic acid ethyl ester, 2-iodopyridine and 2-iodopyrimidine have been studied. The structure of 2,4-dinitrotrifluoromethylbenzene has been elucidated. 相似文献
9.
I. A. Abronin L. G. Gorb V. G. Dryuk V. I. Sheremet Z. F. Solomko M. M. Kremlev 《Chemistry of Heterocyclic Compounds》1981,17(9):954-956
The results of the chlorination of 4-methyl-8-methoxy-2,3-dihydro-1H,1,5-benzodiazepin-2-ones are compared with the results of quantum-chemical calculations of 4-methyl-2,3-dihydro-1H-1,5-benzodiazepin-2-ones with various substituents in the benzene ring in the case of homolytic halogenation. The chlorination of 4-methyl-8-methoxy-2,3-dihydro-1H-1,5-benzodiazepin-2-one (I) with N-chlorosuccinimide leads to 3-chloro- and 3,3-dichloro-4-methyl-8-methoxy-2,3-dihydro-1H-1,5-benzodiazepin-2-ones, whereas chlorination with sulfuryl chloride leads to 4-chloromethyl and 3,3-dichloro-4-methyl derivatives. The IR, PMR, and mass spectra of the synthesized compounds are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1272–1274, September, 1981. 相似文献
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