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1.
| 1. | A new type of sorbents, containing SH groups, was obtained by the modification of aminooxy adsorbents. |
| 2. | The obtained sorbents were used for the covalent immobilization of biologically active compounds with the formation of C-S, C-Hg-S, and S-S bonds. |
2.
| 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. |
3.
N. V. Zakatova D. R. Minkhadzhidinova M. A. Nadzhafova R. F. D'yachkovskaya N. P. Koaovalova V. A. Sharpatyi 《Russian Chemical Bulletin》1976,25(2):434-436
| 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). |
4.
V. A. Smit S. O. Simonyan V. A. Tarasov A. S. Gybin G. S. Mikaélyan A. S. Shashkov S. S. Mamyan I. I. Ibragimov R. Kéipl 《Russian Chemical Bulletin》1988,37(12):2526-2535
| 1. | The intramolecular Khand-Pauson reaction is substantially accelerated when it is carried out on the surface of a Chromatographic adsorbent in the absence of a solvent. |
| 2. | A method has been developed for the preparation of substituted 3-oxabicyclo[3.3.0]-oct-5-en-7-ones, by cyclization of the dicobalt hexacarbonyl complexes of allyl propargyl ethers. |
| 3. | A novel cyclization reaction of dicobalt hexacarbonyl complexes has been found, which provides a convenient synthetic route to 4-hydroxymethylcyclopent-2-en-1-ones. |
5.
L. F. Chertanova G. A. Marchenko A. A. Gazikasheva Yu. T. Struchkov V. F. Sopin L. N. Punegova A. S. Mukhametzyanov 《Russian Chemical Bulletin》1989,38(2):250-253
| 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. |
6.
S. F. Vasilevskii A. N. Sinyakov M. S. Shvartsberg I. L. Kotlyarevskii 《Russian Chemical Bulletin》1976,25(10):2134-2138
| 1. | Depending on the conditions, the reaction of methyl aryl ketones with phosphorus pentachloride leads to products from substitution of the carbonyl oxygen by chlorine, αβ-dichlorovinylarenes, or compounds with higher degrees of chlorination. |
| 2. | By eliminating a molecule of hydrogen chloride under the influence of an equimolar amount of sodium amide in ammonia, substituted, α,β-dichloroethylenes give high yields of the respective 2-chloroacetylene. |
| 3. | The synthesis of a series of ethynyl- and β-chloroethynylpyrazoles from methylpyrazolyl ketones was realized. |
7.
| 1. | In urethane crystals, infinite chains of hydrogen bonds organize the urethane molecules into layers with two principal types of packing: fir-tree and stacked. The stacked packing sometimes leads to the formation of a quasiskeletal structure. |
| 2. | The geometry of the hydrogen bonds is governed by the packing of neighboring molecules. |
| 3. | The frequency of the stretching vibration band of the NH group in IR spectra cannot be used to judge the geometry of hydrogen bonds in crystalline urethanes, since the geometry is governed not only by the H...O interaction of the hydrogen bond N-H...O=C, but also by the total energy of intermolecular interaction. |
8.
G. V. Shustov S. N. Denisenko I. I. Chervin R. G. Kostyanovskii 《Russian Chemical Bulletin》1988,37(7):1422-1427
| 1. | The fluorodeoxygenation of (S)-proline by the action of sulfur tetrafluoride in hydrogen fluoride to (-)-2-trifluoromethylpyrrolidine was realized without affecting the carbon of the chiral center. |
| 2. | According to PMR data, 2-trifluoromethylpyrrolidine, its N-chloro derivative, and 1-chloro-2-methoxycarbonylpyrrolidine exist preferentially in the conformation with the pseudoequatorial orientation of the substituent at position 2. |
9.
Yu. V. Kuznetsov L. G. Stolyarova V. P. Lezina L. D. Smirnov 《Russian Chemical Bulletin》1989,38(7):1494-1500
| 1. | New halogen derivatives of 1-ethyl-2-methyl-, 2-methyl- and 5-hydroxybenzimidazole were obtained. |
| 2. | A method for the chlorination of aromatic compounds by an alcoholic solution of hydrogen chloride in the presence of hydrogen peroxide was proposed, which enables carrying out the reaction with a high yield. |
| 3. | The reactivity of the series of 5(6)-hydroxybenzimidazole derivatives during the electrophilic substitution (halogenation) was shown to be as follows: 1-ethyl-2-methyl-5-hydroxybenzimidazole >5(6)-hydroxybenzimidazole 2-methyl-5-hydroxybenzimidazole. |
10.
A. I. Prokof'ev N. A. Malysheva N. N. Bubnov S. P. Solodovnikov M. I. Kabachnik 《Russian Chemical Bulletin》1976,25(3):494-497
| 1. | A method is proposed for investigating fast reactions of aroxyl radicals. The kinetic parameters obtained for the reaction of 2,4,6-tri-t-butylphenoxyl with phenol and with 4-bromophenol coincide with the data obtained by other methods. |
| 2. | From an analysis of the kinetic data, it is concluded that the OH bond energy in 4-methyl-2,6-di-t-butylphenol is close to that in 2,4,6-tri-t-butylphenol. |
11.
| 1. | A series of C-functional derivatives of (3)-1,2-dicarbaundecaborate was synthesized and some of their properties were studied. |
| 2. | Apparent ionization constants of acids of the (3)-1,2-dicarbaundecaborate series were measured and it was found that they are very weak carboxylic acids. |
| 3. | Upon reaction with excess LiA1H4, under mild conditions the carbonyl, *20c \CH(OH) / \begin{array}{*{20}c} \backslash \\ {CH(OH)} \\ / \\ \end{array} , and CH2OH groups of dicarbaundecaborate ketones and alcohols are reduced to CH2 and CH3 groups, respectively. |
| 4. | The effect of Grignard reagent on ketones and esters of the dicarbaundecarbprate series was studied and it was established that the composition of reaction products depends both on the steric hindrance of the carbonyl group and on the electron-donating effect of the (3)-1,2-dicarbaundecaborate substituent. |
12.
K. L. Rogozhin A. N. Rodionov S. G. Smirnov D. N. Shigorin O. P. Syutkina V. I. Lodochnikova K. A. Kocheshkov 《Russian Chemical Bulletin》1976,25(2):319-322
| 1. | There is a regular increase in the energy of the lowest singlet and triplet excited levels in the aromatic derivatives of the elements C, Si, Ge, Sn and N, P, As, Sb, Bi, which is consistent with the quantum-mechanical model of the mixing of the electronic states of the aromatic system with states involving p and s orbitals of the heteroatom with different energies and symmetries. |
| 2. | The yields of the radiative electronic transitions regularly decrease, and the probabilities of nonradiative intramolecular electronic transitions increase. |
| 3. | The temperature effects inthe 300–77°K range in the electronic absorption spectra have been found and are associated with a postulated change in the spatial configuration of the compounds investigated. |
13.
| 1. | Thermodesorption measurements have shown the surface of aluminum-nickel-tungsten sulfide catalysts to be nonuniform with respect to cyclohexane, the nonuniformity being characterized by an exponential distribution, a step adsorption isotherm, and a logarithmic fall off of the desorption activation energy with increasing surface coverage. |
| 2. | The degree of cyclohexane coverage of the catalyst surface is increased by the presence of hydrogen, and the energy of adsorptional bonding is reduced. |
| 3. | Cyclohexane bonds to the catalyst surface more weakly than does benzene, and can be completely displaced from the surface by the latter. |
14.
B. A. Glazun R. N. Kurnosova M. M. Dubinin I. V. Zhilenkov S. S. Levchenko 《Russian Chemical Bulletin》1976,25(1):8-11
| 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. |
15.
Chipanina N. N. Kazakova N. A. Shestova L. A. Domnina E. S. Skvortsova G. G. Frolov Yu. L. 《Russian Chemical Bulletin》1976,25(4):915-916
| 1. | The energy of the interaction in the electronically excited state was determined from the magnitude of the shift in frequency of the vibronic maximums in the UV spectra of phenol during its formation of hydrogen bonds with 1-ethylpyrazoles, 1-ethyl-, and 1-vinylimidazole. |
| 2. | The most notable change in the energy of the hydrogen bonds during excitation is observed for 1-ethylimidazole which possesses the greatest electron-donor capability in the ground state. |
16.
| 1. | Paramagnetic species quench the triplet exciplexes of contact radical-ion pairs with a rate approaching the diffusion-controlled limit taking account of the spin statistical factor of 1/3. |
| 2. | The quenching mechanism lies in an acceleration in the transition of the radical pair between states with different multiplicity due to removal of the prohibition in the collision complex. |
17.
L. Kh. Freidlin L. I. Gvinter V. A. Zamureenko L. N. Suvorova 《Russian Chemical Bulletin》1976,25(4):795-797
| 1. | Intermediate enol formation has been registered by deuterium exchange in the hydrogenation products of, -unsaturated ketones on Co/C and Rh/C, indicating 1,4 addition of hydrogen to the enone system. |
| 2. | The presence of 1,4 hydrogen addition to,-unsaturated ketones is determined by the nature of the catalyst; Pd/C does not catalyze this process route. |
| 3. | Modification of Pd catalysts with cadmium changes their orienting action and selectivity in favor of 1,4 hydrogen addition with intermediate enol formation. |
18.
B. A. Arbuzov O. Éxsner A. P. Timosheva V. E. Kataev S. G. Vul'fson A. N. Vereshchagin 《Russian Chemical Bulletin》1976,25(6):1206-1212
| 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. |
19.
R. G. Kostyanovskii V. P. Leshchinskaya R. K. Alekperov G. K. Kadorkina L. L. Shustova Yu. I. Él'natanov G. L. Gromova A. É. Aliev I. I. Chervin 《Russian Chemical Bulletin》1988,37(11):2315-2323
| 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. |
20.
Presently, a large variety of layered materials are synthesized that are able to intercalate neutral guest molecules or to exchange inorganic and organic ions for interlayer ions. Several of these materials are also found as minerals.The intracrystalline reactivity of a few selected compounds will be described and compared to clay minerals:
相似文献
| – | - intercalation into crystalline silicic acids; |
| – | - reactions of phosphates, arsenates, and sulfates; |
| – | - reactions of titanates, niobates, and molybdates with long chain alkylammonium ions, and |
| – | - anion exchange properties of double hydroxides. |