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11.
A gas chromatograph for the rapid determination of explosives (2,4-dinitrotoluene, 2,4,6-trinitrotoluene, and pentaerythritol tetranitrate) and narcotics (heroin, cocaine hydrochloride, and crack) is described, and its analytical characteristics are presented. The instrument was equipped with a multicapillary column and an ion-mobility spectrometer as a detector. 相似文献
12.
K. V. Komarov N. D. Chkanikov S. V. Sereda M. Yu. Antipin Yu. T. Struchkov A. F. Kolomiets A. V. Fokin 《Russian Chemical Bulletin》1988,37(8):1717-1719
Conclusions The reactions of -naphthylamine with 2,2-bis(trifluororaethyl)-1,1-dicyanoethylene leads to the formation of 2-amino-4,4-bis(trifluoromethyl)-3-cyano-1,4-dihydrobenzo[h]quinoline. The structure of this product was established by x-ray diffraction structural analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1917–1920, August, 1988. 相似文献
13.
V. Yu. Tyutin N. D. Chkanikov V. S. Shklyaev Yu. V. Shklyaev A. F. Kolomiets A. V. Fokin 《Russian Chemical Bulletin》1992,41(8):1474-1476
1,3,3-Trimethyl-3,4-dihydroisoquinolines react with 1,1-dicyano-2,2-bis(trifluoromethyl)ethylene to give 4-amino-6,6-dimethyl-2,2-bis(trifluoromethyl)-3-cyano-6,7-dihydro-2H-benzo[a]quinolizines. The reaction of 3,3-dimethyl-1-cyanomethylidene-1,2,3,4-tetrahydroisoquinoline and the methyl ester of 3,3-dicyano-2-(trifluoromethyl)acrylic acid leads to 5,5-dimethyl-3-oxo-2-(trifluoromethyl)-2-(dicyanomethyl)-2,3,5,6-tetrahydropyrrolo[2,1-a]isoquinoline.A. N. Nesmeyanov Institute of Heteroorganic Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1888–1892, August, 1992. 相似文献
14.
V. D. Sviridov N. D. Chkanikov M. V. Galakhov A. F. Kolomiets A. V. Fokin 《Russian Chemical Bulletin》1990,39(4):853-855
Methyl trifluoropyruvate (II) reacts with phenylhydrazine andp-nitrophenylhydrazine to give the corresponding phenylhydrazones (III) and (IV). The reaction of phenylhydrazine with hexafluoroacetone (I) at 20°C leads to the product of the C2-hydroxyalkylation of the aromatic ring (V). The hydroxyalkylation of hydrazobenzene under the same conditions is complicated by a benzidine rearrangement.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 948–950, April, 1990. 相似文献
15.
V. K. Bel'skii E. V. Kharchenko A. N. Sobolev V. E. Zavodnik N. A. Kolomiets G. S. Prober L. P. Oleksenko 《Journal of Structural Chemistry》1991,31(5):791-795
Kiev State University and L. Ya. Karpov Physical Chemistry Research Institute. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 5, pp. 116–121, September–October, 1990. 相似文献
16.
A. V. Fokin Yu. A. Borisov A. F. Kolomiets N. I. Raevskii V. G. Enchev E. B. Bogachuk 《Russian Chemical Bulletin》1992,41(2):266-271
The heats of formation of polychloroarynes (PCA's) from polychlorobenzenes (PCB's) have been calculated by the AMI method as a function of the composition and structure of the PCB's according to a two-step scheme including deprotonation with the formation of carbanions (PCCA's, H1) and dechlorination to PCA's (H2). The influence of the solvent on H1 and H2 has been evaluated in the framework of the solvaton model. It has been shown that the value of H1 decreases as the number of C1 atoms in the PCB is increased, while H2 increases along the same series due to the increase in the relative stability of the PCCA as the number of C1 atoms is increased. Although the dimerization of PCA's with the formation of polychlorobiphenylenes (PCBP's) is forbidden by orbital symmetry rules, calculations of fragments of the potential-energy surface have shown that this reaction takes place with an energy barrier amounting to about 1 kcal/mole.A. N. Nesmeyanov Institute of Organometallic Compounds, Russian Academy of Sciences, 117813 Moscow. Institute of Organic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 350–355, February, 1992. 相似文献
17.
D. N. Kolomiets I. D. Troshkina M. F. Sheremet’ev L. V. Konopleva 《Russian Journal of Applied Chemistry》2005,78(5):722-726
The equilibrium and kinetic characteristics of uranium sorption from simulated sulfuric acid leaching solutions by AMP, Lewatit K 6367, Purolite A 500, Purolite A 600, and AM-p gel-like and porous strongly basic anion exchangers were studied.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 5, 2005, pp. 736–740.Original Russian Text Copyright © 2005 by Kolomiets, Troshkina, Sheremet’ev, Konopleva. 相似文献
18.
V. D. Sviridov N. D. Chkanikov A. F. Kolomiets A. V. Fokin 《Russian Chemical Bulletin》1991,40(4):847-849
Diphenylamine reacts with hexafluoroacetone to give a mixture of products, of which 2-(1-hydroxy-1-trifluoromethyl-2,2,2-trifluoroethyl)diphenylamine (II) was isolated. N-Arylanthranilic acids modify the 1,1,1,3,3,3-hexafluoro-2-hydroxy-2-propyl group upon the reaction of its sodium salt with the hydrate of hexafluoroacetone (I) under mild conditions. This method gave 4-(1-hydroxy-1-trifluoromethyl-2,2,3-trifluoroethyl)-N-(2,3-xylyl)anthranilic acid from N-(2,3-xylyl)anthranilic acid in 93% yield.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 952–954, April, 1991. 相似文献
19.
Osipov SN Golubev AS Sewald N Michel T Kolomiets AF Fokin AV Burger K 《The Journal of organic chemistry》1996,61(21):7521-7528
A new method for the preparation of alpha-chlorodifluoromethyl-, alpha-bromodifluoromethyl-, and alpha-difluoromethyl-substituted alpha-hydroxy and alpha-amino acid esters 11, 19-21 is described. The key step of the synthesis is the regioselective alkylation of ketones 5, 7-9 and imines 16-18 with C-nucleophiles. The ketones 7-9 are readily available from 3,3,3-trifluorolactate 1 by a five-step procedure. Subsequent removal of the protecting groups from 19-21 provides the corresponding free amino acids 25, 26, 28. 相似文献
20.
Methyl trifluoropyruvate trifluoroacetylimine (I) reacts regioselectively with olefins to form dihydrooxazines (II)-(VII). In its reactions with 1,3-dienes, too, compound (I) exhibits properties of a 1,3-heterodiene rather than a dienophile. Acid hydrolysis of the synthesized oxazines results in their conversion to substituted -amino--trifluoromethyltetrahydrofuran-2-ones (XII)-(XVI).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1130–1133, May, 1991. 相似文献