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31.
32.
Conclusions The reaction of 1,3-difluoro-1,1,3,3-tetranitropropane with alkanols was used for the preparation of alkyl esters of 3-fluoro-3-nitroacrylic acid. 1,3-Difluoro-1,3,3-trinitro-1- propene and 1,3-difluoro-1,3-dinitro-2-alkoxy-1-propene were also isolated as intermediates.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 709–711, March, 1989. 相似文献
33.
The sorption isotherms of water and tetrachloromethane vapors are studied, and the porous structures of aluminum tin phosphate gels coprecipitated at various Al/Sn molar ratios are analyzed. The resultant samples contain both micro- and mesopores. The structure of aluminum tin phosphate is suggested to contain slitlike pores that do not change during drying because of the presence of polyaquahydroxoaluminum cations introduced via an exchange with interlayer cations of tin(IV) hydrophosphate. 相似文献
34.
B. L. Korsunskii G. V. Sitonina B. S. Fedorov F. I. Dubovitskii L. T. Eremenko 《Russian Chemical Bulletin》1989,38(4):710-713
1. | The thermal decomposition of N,N-dinitroamines is homogeneous and unimolecular in the gas phase. The limiting step of the process is the rupture of the N-NO2 bond. |
2. | The activation parameters of the process imply that the dinitroamine group is more reactive than the mononitroamine group in thermal decomposition. The energy of dissociation of the N-NO2 bond in dinitroamines is 42 kJ/mole less than in mononitroamines. |
3. | Nitrogen dioxide and acetaldehyde do not influence the kinetics of thermal decomposition of dinitroamines due to their high reactivity. |
35.
E. V. Stenina L. N. Sviridova A. G. Krivenko L. B. Romanova L. T. Eremenko 《Russian Journal of Electrochemistry》2003,39(10):1017-1024
A synthesis and a study by method of measuring the differential capacitance on a stationary mercury drop of the adsorption of a number of cubane derivatives in a surface-inactive electrolyte are performed. It is established that the compounds studied exhibit a high surface activity. For bromine derivatives of cubane (4-bromomethoxycarbonylcubane, 4-bromohydroxymethylcubane) the formation of two-dimensional adsorption layers is discovered. Values of adsorption parameters for these compounds are evaluated with use made of the Frumkin isotherm. 相似文献
36.
Synthesis and Catalytic Properties of Di- and Trinuclear Palladium Complexes with PCP-Pincer Ligands
Beletskaya I. P. Chuchuryukin A. V. van Koten G. Dijkstra H. P. van Klink G. P. M. Kashin A. N. Nefedov S. E. Eremenko I. L. 《Russian Journal of Organic Chemistry》2003,39(9):1268-1281
Linear and branched conjugated pincer ligands having Ph2P groups were synthesized: 3,3',5,5'- tetrakis(diphenylphosphinomethyl)diphenylacetylene, 3,3',5,5'-tetrakis(diphenylphosphinomethyl)diphenyldi- acetylene, 1,3,5-tris[3,5-bis(diphenylphosphinomethyl)phenylethynyl]benzene, and hexakis[3,5-bis(diphenylphosphinomethyl)phenylethynyl]benzene. Palladation of these ligands by heating with Pd(BF4)2(MeCN)4 in boiling acetonitrile gave the corresponding di- and trinuclear ionic pincer palladium complexes. No individual complex was obtained from hexakis[3,5-bis(diphenylphosphinomethyl)phenylethynyl]benzene. The ionic com- plexes were converted into the corresponding chloride complexes by treatment with sodium chloride in a mixture of water with methylene chloride. The structure of the ionic palladium complex with 3,3',5,5'-tetrakis(diphenylphosphinomethyl)diphenylacetylene was established by X-ray analysis. The obtained palladium complexes exhibited a considerable catalytic activity in the Heck reaction of iodobenzene with ethyl acrylate and in the Michael addition of ethyl cyanoacetate with methyl vinyl ketone. The catalytic activity per palladium atom decreases as the number of palladium atoms in the complex increases. 相似文献
37.
V. P. Kondilenko A. M. Eremenko I. G. Tarasov V. M. Ogenko 《Theoretical and Experimental Chemistry》1996,32(5):281-284
In the formation of a pyrene/N,N-dimethylaninline exciplex solubilized in micelles of the nonionic surfactant Triton X-100, under conditions of adsorption on the surface of Aerosil (pyrogenic silica), the features of the reaction are determined by the restructuring of the Aerosil surface in the aqueous micellar medium and by encapsulation of the fluorophore molecules.Institute of Surface Chemistry, National Academy of Sciences of the Ukraine, 31 Nauka Prospect, Kiev 252039, Ukraine. Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 32, No. 5, pp. 320–323, September–October, 1996. Original article submitted June 16, 1995. 相似文献
38.
L. T. Eremenko L. B. Romanova M. E. Ivanova V. S. Malygina L. S. Barinova G. V. Lagodzinskaya V. P. Lodygina I. L. Eremenko G. G. Aleksandrov 《Russian Chemical Bulletin》2007,56(7):1408-1422
New substituted cubane-1,4-dicarboxamides and 4-bromocubanecarboxamides containing the nitroxyl group and amino acid fragments along with the cubane skeleton were synthesized. The cardiac pharmacological activity (both the effect on aorta relaxation and the calcium channel blocking activity) of most of nitroxyalkyl derivatives is equal to or higher than that of N-(2-nitroxyethyl)nicotinamide (nicorandil). 相似文献
39.
Sidorov A. A. Fomina I. G. Talismanov S. S. Aleksandrov G. G. Novotortsev V. M. Nefedov S. E. Eremenko I. L. 《Russian Journal of Coordination Chemistry》2001,27(8):548-559
Transformations of polymeric trimethylacetate complexes [M(OH)
n
(OOCCMe3)2 – n
]
m
(M = Ni (I) and Co (II)) and clusters Ni9(4-OH)3(3-OH)3(-O,O-OOCCMe3)(-O,O"-OOCCMe3)7(3-O,O,O"-OOCCMe3)3(4-O,O,O",O"-OOCCMe3)(HOOCCMe3)4(III) and Co6(3-OH)2(-OOCCMe3)10(HOOCCMe3)4(VIII), which are formed from Iand IIupon their recrystallization from nonpolar solvents, were studied. It was shown that the action of N-phenyl-o-phenylenediamine (L) on Ior IIIresults, depending on the solvent, in different tetranuclear clusters with the hydroxo bridges. For example, in benzene, the L2Ni4(3-OH)2(HOOCCMe3)4(-OOCCMe3)6complex (IX) is formed; its L molecules are coordinated in a monodentate way, whereas in acetonitrile, they chelate to give the {[o-C6H4(NH2)(NHPh)]2Ni4(3-OH)2(MeCN)2(OOCCMe3)2(-OOCCMe3)4} compound (X). Heating of Xin the presence of atmospheric oxygen yields IX, the mononuclear bissemiquinonediimine [o-C6H4(NH)(NPh)]2Ni complex (XI), and water. It was noted that the use of aniline in these reactions affords, independent of the nature of the solvent, only one (NH2C6H5)2Ni4(3-OH)2(HOOCCMe3)4(-OOCCMe3)6cluster (VI); in acetonitrile, this cluster is formed as the solvate VI· 2HOOCCMe3(VIa). When treated with ethanol, Iand IIIgive the Ni4(EtOH)6(3-OH)2(2-OOCCMe3)4(OOCCMe3)2cluster (V), which is structurally close to the known cobalt-containing analog IV. Thermolysis of IVin decalin at 170° causes its dimerization, giving the octanuclear Co8(4-O)2(
n
-OOCCMe3)12complex (VII) with the tetradentate oxo bridges. 相似文献
40.
A precision X-ray structural investigation of 1,4-dimethoxycarbonylcubane at 218 K was carried out. Analysis of the experimental maps of deformational electron density indicates the existence of partial electron density transfer from the cage bonds to the Ccubane-COOR bonds and the shift of the electron density to the symmetrical (relative to the COOMe planes) cube faces.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1210–1213, July, 1993. 相似文献