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1.
1.  N-Ethyl and N-isopropyl-3-piperidones were synthesized and the stereochemistry of their reduction was studied.
2.  The dependenceof stereochemistryof a series of reactions at the carbonyl center on bulk of the substituent on nitrogen was established.
3.  Pure a- and e-epimers of N-ethyl- and N-isopropyl-3-piperidols were separated.
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2.
1.  The condensation of 1,2-hydroxylamino oximes with biacetyl leads to 1-hydroxy-2-acetyl-2,4,5,5-tetrasubstituted 3-imidazoline 3-oxides.
2.  When 1-hydroxy-2-acetyl-2,5,5-trimethyl-4-phenyl-3-imidazoline 3-oxide is oxidized the CH3CO group is cleaved to give the 5H-imidazole 1,3-dioxide.
3.  Stable nitroxyl radicals were obtained when the 1-hydroxy-2-oximiaoethyl-2,4,5,5-tetrasubstituted 3-imidazoline 3-oxides are oxidized.
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3.
1.  In NaA zeolite a homocharge is formed by charges deposited on the surface of the zeolite from the gas gap between the electrode and the specimen.
2.  The existence of thermoelectret effects has been found in the systems NaA-zeolite -air, NaA-helium, NaA-nitrogen, and NaA-oxygen.
3.  The thermoelectret effects are caused by both the accumulation of charges in the specimen and the adsorption of molecules in the electric field.
4.  A low mobility has been noted for adsorbed molecules in the electret state of the system.
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4.
1.  Nitroxyl biradicals of the triazine, N,N-bis(triazinyl)ethylenediamine, N,N-bis(triazinyl)piperazine, and s-nitropyrimidine series have been prepared.
2.  The ESR spectra of liquid and frozen solutions of these biradicals have been obtained and N. - O group separations calculated.
3.  Toluene solutions of (II), (V), (VI), and (X) biradicals contain at least four different conformations, each with its own value of the exchange integral.
4.  In one of the biradical (V) conformations, spin interaction exchange is through the chain of atoms linking the N.-O fragments.
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5.
1.  The dipole moments of the two kinds of C-O bonds in acetals and their analogs are not identical.
2.  In formal molecules and the dimethylketal of acetone the C-O-C-O -C chains have gauche-gauche conformation, with the methyl groups lying on different sides of the O-C-O plane.
3.  The dimethylketal of tetrachlorocyclopentadienone is represented by a mixture of trans-gauche and gauche-gauche conformers.
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6.
1.  The planar alkoxydiazinoxide fragments are shown to have the Z-configuration and be orthogonal to each other by an x-ray structure study of a series of alkoxydiazinoxides.
2.  In the oxydiazinoxide fragments, p- conjugation occurs.
3.  The molecules of the compounds in the crystals studied are joined by hydrogen bonds.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 297–301, February, 1989.  相似文献   

7.
1.  The molecular-sieve properties of a number of synthetic and natural chabazites have been investigated.
2.  Characteristic differences have been revealed in the molecular-sieve properties, thermal stability, and x-ray characteristics between the two groups of the zeolites studied.
3.  A reversal of the molecular-sieve effect on passing from the calcium to the sodium-calcium forms of certain synthetic and natural chabazites has been observed.
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8.
1.  An efficient method of aziridine dimer synthesis is presented involving reaction of aziridine with esters of strong organic acids followed by alkaline hydrolysis of the resultant N-acyl derivatives.
2.  New N-acyl and carbamoyl derivatives of aziridine dimer and trimer were synthesized.
3.  Linear and branched isomers of aziridine tetramer and also diastereomers of 2-methylaziridine dimer were isolated and characterized.
4.  An efficient regiospecific synthesis of 2,2-dimethylaziridine dimer and trimer was developed.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2566–2575, November, 1988.  相似文献   

9.
1.  Study has been made of the kinetics of the-elimination of alcohol from 3-carbethoxy-4-ethoxy-2-pentanone in benzene and under the catalytic action of acetic acid.
2.  This reaction involves formation of a complex between substrate and acetic acid.
3.  The equilibrium constant for the reaction of forming the complex between substrate and acetic acid, and the rate constant for complex formation, have both been determined.
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10.
1.  It has been shown that 2-bromo-l,3,2-dioxaarsenanes exist in chair conformation with axially oriented As-Br bonds.
2.  Polarity and polarizability parameters have been found for the As-O and As-Br bonds in 2-bromo-l,3,2-dioxaarsenanes.
3.  The so-called -effect is stronger in the O2AsBr group than in the O2AsCl group.
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11.
1.  Depending on the nature of the substituent in the 2 position, l-fluoro-l-(-hydrohexafluoroisopropyl)ethylenes are dehydrofluorinated to either allenes or 1,3-dienes.
2.  It was shown that allylic substitution is possible in the reactions of perfluoroisobutylene with carbanions; the mutual transformations of the allyl and vinyl isomers were studied.
3.  The perfluoroalkenylation product was obtained when perfluoroisobutylene is reacted with ketene acetal.
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12.
1.  Potentiometric titration in nitromethane at 25°C has been used to determine dissociation constants for 16 mono-substituted benzoic acids.
2.  Brönsted and Hammett equations have been set up for the compound series under study here.
3.  The data of the literature have been used to evaluate the nitromethane autoprotolysis constant, pKS24.
4.  The relative differentiating action of nitromethane with respect to other solvents has been evaluated from the slopes of the Brönsted and Hammett plots and the values of the autoprotolysis constant. The differentiating action of nitromethane with respect to acids is greater than that of acids with respect to alcohols and acetone, but less than that of DMSO, acetonitrile, and DMF.
5.  Study has been made of the dissociation of the aminobenzoic acids in nitromethane. Solutions of p-aminobenzoic acid are free of zwitterions, while solutions of the m-aminobenzoic acid contain these ions to the extent of 50%.
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13.
1.  Following the CNDO/2 approximation to the SCF MO LCAO method, electronic parameters have been calculated for the molecules and ions of various nitro compounds.
2.  Calculated values of the dipole moment and enthalpy of atomization proved to be in satisfactory agreement with the experimentally determined values, the maximum deviation between them amounting to 1.4% for the aromatic systems.
3.  The nitro compound parameters most sensitive to change in the intramolecular interaction are the C-N bond energy and the charges on the carbon and halide atoms.
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14.
1.  We determined the reactivity of some nitrogen bases, and of a number of amino acids and bis-(diazoacetyl)alkyl derivatives toward the electron at 77°K.
2.  The effect of the pH at 77°K as established on the yield of the deamination process and the reactivity of the studied amino acids toward the electron.
3.  It was found that the yield for the deamination of glutamic acid is increased in the presence of inositol (acceptor of OH radicals).
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15.
1.  The reaction of 6-nitro-2,9-dioxa-1-azabicyclo[4.3.0]nonane derivatives with alcohols and alcoholates leads to remplacement of the nitro group by the corresponding alkoxy group.
2.  The reaction proceeds with either a complete (for the case of the alcoholates) or predominant (for the case of alcohols) inversion of the configuration at the substitution center.
3.  The reaction proceeds via the intermediately formed bicyclic immonium cation.
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16.
1.  The previously unknown aminooxyalkylcelluloses have been synthesized by alkylation of cellulose with N-substituted -haloalkylhydroxylamines.
2.  The prepared aminooxyalkylcelluloses are weak ion-exchangers, readily react with many classes of organic compounds, and are stable during storage.
3.  Methods have been developed for the preparation of aminooxyalkylcelluloses with different lengths of the pendant H2NO group on the polysaccharide framework.
4.  Sorbents were prepared, based on the aminooxyalkylcelluloses, which contained a covalently bonded coenzyme (pyridoxal-5-phosphate), a substrate (-ketoglutaric acid) and functional groups, able to react with certain functional groups of biopolymers.
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17.
1.  Complexes of the REE, Y, and Sc with hydroxyethylethylenediaminetriacetic acid have been isolated in solid form. The hydrate compositions of the complexes have been determined.
2.  The La and Pr complexes form hydrates of different compositions. The LnL hydrates form slightly nonisostructural groups in the series La-Lu.
3.  According to thermographic analysis data, the hydrate water in the LnL·nH2O complexes of different hydrate compositions is not bonded with the same firmness.
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18.
1.  New representatives of diarylketiminoboranes with alkyl and aryl substituents on the boron atom were obtained upon reaction of diarylketimine hydrochlorides and aminoboranes.
2.  Data on dipole moments of the investigated diarylketiminoboranes do not confirm the dipolar structure assigned to them.
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19.
1.  The ellipsoids of polarizability of dimethylsulfone, sulfuryl chloride, and methanesulfonyl chloride were determined, and the nonadditivity of the parameters of the bonds in the sulfonyl chloride group was demonstrated.
2.  Substituted methane sulfonyl chloride exist in gauche conformations.
3.  In benzenesulfonyl chloride and a series of its para-substituted derivatives, the aryls are situated in the C-S-Cl plane; the para-nitro group induces a 35° rotation.
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20.
1.  Vinyl- and isopropenyl-o-carborane are hydrogenated under the reaction conditions for the hydroformylation and carboxylation of olefins in the presence of cobalt or rhodium carbonyls.
2.  A mechanism was proposed for the hydrogenation of olefin-o-carboranes in alcohol solutions under CO pressure.
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