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1.
| 1. | Replacing Na+ ions by Ca2+in zeolites leads to a significant shift of the region in which thermally stimulated polarographic [TSD] current peaks appear toward higher temperatures. |
| 2. | Reducing the cation content in zeolites leads to a decrease in the intensity of TSD currents. |
| 3. | The data obtained-can be explained by the differences in the distributions of the cations between different crystallographic positions in the zeolite lattices. |
2.
Ya. I. Isakov Kh. M. Minachev G. V. Isagulyants Yu. S. Akhmetov N. N. Rozhdestvenskaya 《Russian Chemical Bulletin》1976,25(11):2267-2270
| 1. | By14C labeling, it has been shown that carbon dioxide will adsorb differently on various synthetic Ca2+-ion-containing zeolites (CaNaY, and dealuminated CaNaY and CaNdNaY) on which benzene is being alkylated by ethylene. The promoting action of CO2 is due to the presence of a weakly adsorbed form of the compound which can be readily displaced by N2 at the reaction temperature. |
| 2. | The CO2 content of the catalyst and its time variation are dependent on the zeolite composition, the re-action temperature, and the moisture content of the CO2. |
| 3. | Under fixed operating conditions, the CO2 content of zeolite 0.67CaNaY and its time variation are the same for C6H6 alkylation by ethylene and for toluene disproportionation. |
3.
Kh. M. Minachev E. S. Mortikov A. A. Masloboev N. F. Kononov N. V. Mirzabekova 《Russian Chemical Bulletin》1976,25(8):1682-1685
| 1. | Given the same conditions on interaction between benzene and ethylene on the zeolites with Ca and REE, essentially ethylbenzene is formed; on the zeolites with the Ni and Fe cations essentially a secondary butylbenzene is formed; and on the zeolites with the trivalent Cr, a high-molecular-weight polyethylene is formed. |
| 2. | A determining role of adsorption of one of the reactants in the change of the selectivity of zeolites with different cations has been demonstrated. |
4.
| 1. | An increase in the SiO2/Al2O3 ratio (x) in type Y zeolites through dealuminization with ethylenediaminetetraacetic acid leads to an increase in their catalytic activity during the alkylation of benzene with ethylene. |
| 2. | The properties of CaNaY zeolites of the same composition prepared from NaY obtained by hydrothermal synthesis and by dealuminization of samples with a small value of x are identical. |
| 3. | Carbon dioxide exerts an accelerating effect on the Ca forms of dealuminized type Y zeolites of various compositions and has no effect on the properties of NaY'. |
5.
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. |
6.
B. A. Nabiev L. I. Lafer V. I. Yakerson A. M. Rubinshtein 《Russian Chemical Bulletin》1976,25(7):1398-1402
| 1. | CO2 interacts with the hydrogen forms of type Y zeolites, erionite, and mordenite without experiencing any loss in symmetry. |
| 2. | The adsorption of CO2 at 20°C on zeolites containing monovalent cations involves ion-dipole cation interaction in the case of A, X, and Y zeolites, erionite, and mordenite, and the formation of more stable carbonate structures in the case of the A, X, and Y zeolites. Transition between the bidentate coordinated carbonate structure and the carbonate ion proceeds through adsorbed forms of CO2 resulting from ion-dipole interactions. |
| 3. | The symmetry of stable carbonate structures established on the Ca forms of zeolites A, X, and Y can alter under the action of various adsorbates. |
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. |
8.
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. |
9.
| 1. | The (Cp2TiCl)2-LiAlH4 system with Al/Ti from 0.25 to 1.5 catalyzes both the homogeneous hydrogenation and isomerization of allylbenzene. |
| 2. | In an argon atmosphere, allylbenzene is isomerized to trans-propenylbenzene with 90–92% selectivity when Al/Ti=1–1.5. |
| 3. | The possibility was demonstrated for reactivation of this catalytic system by its retreatment with LiAlH4. |
10.
Zh. L. Dykh L. I. Lafer V. I. Yakerson A. M. Rubinshtein A. M. Taber I. V. Kalechits S. S. Zhukovskii V. É. Vasserberg 《Russian Chemical Bulletin》1976,25(2):282-286
| 1. | At 20–220° on aluminum oxide and NaX, NaY, CeNaY, and HY zeolites, aliene isomerizes to methylacetylene; zeolites whose IR spectra are characterized by the presence of absorption bands of the hydroxyl groups (CeNaY, HY) are more active in this reaction. |
| 2. | The thermal dimerization of aliene at 450° proceeds with the formation of 1,2-dimethylenecyclobutane. |
| 3. | The oligomerization of aliene on -allylnickel bromide, applied on aluminum oxide, at 20–180° gives chiefly 1,3-dimethylenecyclobutane, the formation of which evidently proceeds through a four-membered active complex. |
11.
A. Kh. Khusid G. V. Kryshtal' V. F. Kucherov L. A. Yanovskaya 《Russian Chemical Bulletin》1976,25(2):396-399
| 1. | A method was developed for the synthesis of acetals and aldehydes of the cyclopropane series by reducing the acetals of 1,1-dichlorocyclopropanes with sodium in liquid ammonia. |
| 2. | A method was proposed for the synthesis of 1,1-dichloro-2-methyl-3-(3-formylvinyl)cyclopropane. |
12.
N. V. Borunova P. G. Antonov Yu. N. Kukushkin Ya. G. Mukhtarov A. N. Shan'ko L. Kh. Freidlin 《Russian Chemical Bulletin》1976,25(5):948-952
| 1. | The catalytic activity of new complexes of Pt (II)-Sn (II) with dimethylacetamide and DMF in isomerization and hydrogenation reactions of compounds containing a C=C bond is greater than the activity of the Pt-SnCl3 complex by a factor of 4–5. |
| 2. | All the examined complexes catalyzed the selective hydrogenation of phenylacetylene to styrene, and diphenylacetylene to diphenylethane passing through the stilbene stage. |
13.
G. K. -I. Magomedov L. V. Morozova V. N. Kalinin L. I. Zakharkin 《Russian Chemical Bulletin》1976,25(11):2419-2421
| 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. |
14.
| 1. | The reaction of substituted 2-aminopyridines with acetylene gives the corresponding 1-vinyl-2-pyridones. |
| 2. | The vinyl group and heterocycle in 3-, 4-, and 5-methyl-1-vinyl-2-pyridones and 5-chloro-1-vinyl-2-pyridone are coplanar and the vinyl group has trans orientation relative to the carbonyl group. The vinyl group in 6-methyl-1-vinyl-2-pyridone is significantly extruded from the plane of the heterocycle. |
15.
L. S. Golovkina G. V. Rusinova N. S. Vorob'eva Z. K. Zemskova Al. A. Petrov 《Russian Chemical Bulletin》1988,37(3):478-483
| 1. | The mass spectra of saturated tricyclic hydrocarbons with the composition C13H22 were studied, and the possibility of identification of each structural isomer was demonstrat. |
| 2. | The differences in the spectra of the stereoisomers that reflect the peculiarities of their three-dimensional structures were ascertained. The identification of the stereoisomers is not possible in all cases. |
16.
A. L. Lapidus A. Yu. Krylova G. V. Kozlova L. T. Kondrat'ev T. N. Myshenkova 《Russian Chemical Bulletin》1989,38(5):896-899
| 1. | Cobalt-silica-gel catalysts obtained by impregnation with cobalt nitrate were more active than samples of the same composition prepared from cobalt carbonyl. Treatment of the catalysts in a CO2 stream at 20°C led to an increase of the yield of the liquid hydrocarbons. |
| 2. | With increasing cobalt content in the catalysts, the yield of liquid products of the synthesis of hydrocarbons from CO and H2 and the content of n-paraffins in them increased. |
17.
| 1. | Study has been made of the fragmentation paths in chemical ionization of β-methyl-2,3,4,6-tetra-O-methyl-D-galactopyranoside. |
| 2. | The quasimolecular ions of this compound are capable of successive splitting of one, two, and three methanol molecules, the preferred positions for methoxyl elimination being 1, 3, and 4, respectively. |
18.
| 1. | The kinetics of the selective hydrogenation of isoprene to isoamylenes in a circulation-flow system in the vapor phase on a palladium-lead catalyst was studied; the results indicate a sequential mechanism of selectivity. An equation was derived describing the kinetics of the process. |
| 2. | A kinetic model of the process was proposed, satisfying the aggregate of data obtained. |
19.
| 1. | 2-Methyl-2-peroxytetrahydrofuran under the influence of FeSO4 or the FeSO4-CuSO4 system decomposes to give 3-acetoxypropyl radicals, which predominantly recombine to 1,6-hexanediol diacetate. |
| 2. | When 2-methyl-2-peroxytetrahydrofuran is reduced with FeCl2, or with the FeSO4-FeCl3 system, the generated 3-acetoxypropyl radicals are oxidized to 3-acetoxypropyl chloride. |
20.
| 1. | Complexes of platinum with polyethyleneimine have been synthesized and characterized by spectroscopic methods. |
| 2. | It has been shown that the complex Pt(II)-PEI, reduced with sodium borohydride, is an active and selective catalyst for the hydrogenation of aromatic nitro-compounds. |