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931.
A. Ya. Strakov M. V. Petrova N. N. Tonkikh A. I. Gurkovskii Yu. Popelis G. P. Kreishman S. V. Belyakov 《Chemistry of Heterocyclic Compounds》1997,33(3):321-332
The reactions of 2-acetyldimedone and 2-acetyl-3-methoxy-5,5-dimethylcyclohex-2-en-1-one with 3,4-diaminobenzophenoneproduce2-[1-(2-amino-5-benzoylphenyl)amino]ethylidene-5,5-dimethyl-1,3-cyclohexanedioneand 2-acetyl-3-(2-amino-5-benzoylphenyl)amino-5,5-dimethylcyclohex-2-en-1-one, which are cyclized by the action of hydrochloric acid, yielding the respective hydrochlorides of 8-benzoyl- and 7-benzoyl-3,3,11-trimethyl-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepin-2-ones. Hydrolytic cleavage of the 8-benzoyl derivative leads to 2-acetyl-3-(2-amino-4-benzoylphenyl)amino-5,5-dimethylcyclohex-2-en-1-one. A similar cleavage to form 2-acetyl-3-(2-aminophenyl)amino-5,5-dimethylcyclohex-2-en-1-one is observed for the known hydrochloride of 3,3,11-trimethyl-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepin-2-one. The structures of the products were confirmed by PMR spectra and x-ray diffraction data.Riga Technical University, Riga LV-1658. Latvian Institute of Organic Chemistry, Riga LV-1006. University of Cincinnati, Ohio, USA. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 379–391, March, 1997. 相似文献
932.
V. P. Litvinov Yu. A. Sharanin M. P. Goncharenko V. D. Dyachenko A. M. Shestopalov 《Russian Chemical Bulletin》1991,40(8):1675-1681
The reaction of 3-cyano-1,4-dihydropyridine-2-thiolates and the corresponding selenolates with allyl bromide gave 2-allylthio- and 2-allylseleno-3-cyano-1,4-dihydropyridines, which, upon heating in various solvents or in the solid state, undergo [3,3]-sigmatropic rearrangement to give 3-cyano-3-allyl-1,2,3,4-tetrahydropyridine-2-thiones and the corresponding selenones. The resultant pyridinethiones are alkylated by alkyl halides at the sulfur atom and are oxidized by iodine to give disulfides.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1888–1895, August, 1991. 相似文献
933.
V. V. Zakharov G. P. Bugaeva N. Yu. Andreeva L. B. Romanova L. T. Eremenko 《Russian Chemical Bulletin》1998,47(11):2226-2228
The reduction of 1-bromo-9,9-ethylenedioxypentacyclo[4.3.0.02,5.03,8.04,7]nonane-4-carboxylic acid (2) with lithium aluminum hydride and aluminum hydride in THF was studied. A new effective method for preparing 1-bromo-9,9-ethylenedioxypentacyclo[4.3.0.02,5.03,8.04,7]-non-4-ylcarbinol (1) based on reduction of2 with AlH3 under mild conditions was developed. 相似文献
934.
S. V. Fedorov A. Yu. Rulev N. N. Chipanina A. M. Shulunova V. G. Nenajdenko E. S. Balenkova D. A. Tyurin V. K. Turchaninov 《Russian Chemical Bulletin》2005,54(1):103-107
The molecular structures of β-amino-α-bromovinyl trifluoromethyl ketones was studied by UV, IR, 1H, 13C, and 15N NMR spectroscopy and using the density functional (B3LYP/6-31G(d,p) and PBE/QZ3P) and ab initio riMP2/cc-pVTZm quantum-chemical calculations. Factors affecting stabilization of the EZE-conformation of the molecules, which is atypical of analogous unsubstituted amino enones, are considered.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 102–106, January, 2005. 相似文献
935.
Yu. G. Ignat'ev 《Russian Physics Journal》1982,25(11):1063-1065
An exact solution of the equations of relativistic hydrodynamics is obtained for a semiinfinite ideal fluid with the equation of state =p in the field of a plane gravitational wave.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 99–102, November, 1982. 相似文献
936.
S. I. Sin'kov Yu. A. Sapozhnikov B. F. Myasoedov 《Journal of Radioanalytical and Nuclear Chemistry》1990,145(2):113-121
The interaction of short-lived Rn-daughter products /SLDP/, viz.214Pb and214Bi dissolved in sea-water with Fe/III/ hydroxide colloids followed by flotation of combined Fe-SLDP particles at the sea-air interface subsequently generating marine aerosols enriched in214Bi and214Pb have been studied under laboratory conditions. Rate constants for attachment of214Bi and214Pb to dispersed Fe/III/ colloids in the sea water are found to be 3.7×10–4 min–1 litre [g/Fe/]–1 and 2.4×10–4 min–1 litre [g/Fe/]–1, resp., /20°C/ over the concentration range of iron /III/ from 8 to 120 g liter–1. The suggested mechanism of colloid flotation and aerosol generation might be responsible for some peculiarities of SLDP distribution in the lower marine atmosphere. 相似文献
937.
Ya. Yu. Stepanskii N. P. Evmenenko G. S. Yablonskii V. I. Bykov 《Reaction Kinetics and Catalysis Letters》1980,14(3):335-339
Self-oscillation found experimentally in the cool-flame combustion of a model n-heptane-i-octane mixture has been studied in dependence on the composition of the reaction mixture. Calculations based on the CSTR model are in qualitative agreement with experimental data.
--. . .相似文献
938.
Yu. I. Vesnin 《Journal of Structural Chemistry》1995,36(4):655-660
Published experimental data on the dependence of the properties of crystal substances on crystal size are discussed. The dependence
is of the same form for different properties and different crystal substances. When the crystal diminishes in size, its properties
remain constant until the size decreases to 10−5–10−6 cm; smaller crystals considerably change their properties. It is shown that the currently available experimental data are
sufficient to substantiate the notion of an “elementary unit of a solid crystal” (“crystal quantum”). The elementary unit
of a crystal is regarded as a basis for the secondary structure (macrostructure) of a solid and an elementary carrier of its
“crystal” properties. Due to this notion, we can interpret the vast experimental material on the real structures and properties
of solids from a single viewpoint.
Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 4, pp. 724–730, July–August, 1995.
Translated by L. Smolina 相似文献
939.
The mechanism of the reaction of N-aminoethyleneimine with some aliphatic aldehydes and with acrolein have been studied. It has been shown that the reaction takes place at the carbonyl bond C=O with the formation of hydrazones.For part II, see [1]. 相似文献
940.
The synthesis of 2-alkyl(dialkyl)amino-4-chloro-sym-triazine derivatives of hydroxylamine, N-methylhydroxylamine, and N-phenylhydroxylamine has been effected and their properties have been studied. The thermal and catalytic polycondensation of the 2-alkyl(dialkyl)amino-4-chloro-6-N-phenyl(methyl)hydroxyamino-sym-triazines accompanied by the liberation of hydrogen chloride and the formation of linear polycondensates with 3–4 members has been observed.For part IX see [9]. 相似文献