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1.
A simple and effective technique for calculating the transient signals in three-level spin systems irradiated at one and two frequencies is described. All possible signals are presented and discussed. The application of the two-frequency excitation technique for the investigation of the inhomogeneity of the crystalline lattice is suggested.  相似文献   
2.
Liquid-phase condensation of 3-, 4-, and 8-aminoquinolines with aliphatic and aromatic aldehydes catalyzed by transition and rare-earth metal complexes is an efficient method for synthesis of substituted 1,7- and 1,6-naphthyridines and 1,10-phenanthrolines.Institute of Organic Chemistry, Ural Branch, Russian Academy of Sciences, 450054 Ufa; Eastern Scientific-Research Institute of Coal Chemistry, 620219 Sverdlovsk. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 1139–1148, May, 1992.  相似文献   
3.
Conclusions The linear codimerization of 2-cyclopropyl-1,3-butadiene with methyl acrylate gave a mixture of methyl esters of 5-cyclopropyl-2Z,5Z- and 2E,5Z-heptadienoic acids.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2364–2366, October, 1984.  相似文献   
4.
Conclusions The homodimerization of spiro{bicyclo[2.2.1]hepta-2,5-diene-7,1-cyclopropane} (I) has been investigated in the presence of Ni-, Fe-, Co-, Rh-, and Ir-based metal complex catalysts. Depending on the nature of the metal and its ligand environment cyclodimerization of (I) can take place via [2+2]-, [2+2+2]-, and [4+4]-cycloaddition schemes, to give high yields of hepta-, octa-, and nonacyclic strained hydrocarbons.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2592–2599, November, 1988.  相似文献   
5.
Conclusions We were the first to study the cyclic homo- and cooligomerization of 2-cyclopropyl-1,3-butadiene with butadiene and isoprene in the presence of catalysts based on nickel. The conditions were found for obtaining 1,5-dicyclopropyl-1,5-cyclooctadiene, 1-cyclopropyl-1,5-cyclooctadiene, 1-cyclopropyl-5-methyl-1,5-cyclooctadiene, and 1-cyclopropyl-5,9 (8)-dimethyl-1,5,9-cyclododecatriene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2634–2636, November, 1979.  相似文献   
6.
Abstract

FeCl3·6H2O-catalyzed Ritter amidation of deltacyclene and hexacyclic norbornadiene dimers containing both a double bond and a three-carbon ring in the molecule with acetonitrile and water was performed. Depending on the hydrocarbon structure, the reaction proceeds via C-C bond cleavage in the three-carbon ring or at the double bond to form the corresponding N-acetamides.  相似文献   
7.
The structures of the dimerization products of spiro(bicyclo[2.2.1]hepta-2,5-diene-7,1-cyclopropane) have been solved using13C NMR spectroscopy and their stereochemical assignments made. The methylene carbon atom signals for the spirocyclopropane fragment can be used as diagnostic signals in making the stereochemical assignments.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 559–564, March, 1990.  相似文献   
8.
Russian Journal of Organic Chemistry - Binder-free iron- and nickel-containing micro-, meso-, and macroporous zeolites FeHY and NiHY were found to effectively catalyze Knoevenagel condensation of...  相似文献   
9.
Granular binder-free Y-zeolite with a degree of Na+/H+ ion exchange of 0.97 efficiently catalyzed isomerization of tetracyclo[6.2.1.13,6.02,7]dodecane and (2aR,5aα,8aR,8bα)-dodecahydroacenaphthene (perhydroacenaphthene) to 1,3-dimethyladamantane.  相似文献   
10.
Catalytic chlorination of alkanes, cycloalkanes, and adamantane utilizing tetrachloromethane as the source of chlorine and applying catalysts containing manganese, molybdenum, vanadium, and iron activated with nitrile ligands, alcohols, and water was fulfilled. The optimum ratios of catalysts and reagents and the best reaction conditions were found for selective synthesis of chlorine-substituted hydrocarbons derivatives.  相似文献   
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