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1.
M. M. Ermilova N. V. Orekhova E. V. Skakunova V. M. Gryaznov 《Russian Chemical Bulletin》1988,37(4):637-640
| 1. | In the course of catalytic hydrogenation reactions of cyclopentadiene, cyclooctadiene, and isoprene; and in the catalytic hydrogenolysis of propane, all of which proceed at 373–573 K, a.catalytic etching of a palladium-ruthenium membrane catalyst is taking place; it is determined by the nature of the reagents. |
| 2. | An oxidative-reductive treatment changes the surface structure, the catalytic activity, and the hydrogen permeability to a much lesser degree than when such a treatment is alternated with actual catalytic reactions. |
| 3. | A heat treatment followed by a subsequent rapid cooling from temperatures above the recrystallization temperature, increases significantly the activity of a palladium-ruthenium membrane catalyst in the hydrogenolysis of propane. |
2.
| 1. | Alkylarylketiminoboranes react with nitriles to form boron -diiminates, whose structure has been determined by UV, IR, PMR, and boron-11 NMR spectroscopy. |
| 2. | Depending on their structure, boron -diiminates are hydrolyzed in an acid medium with the formation of either boron -diketonates, or -diketones. |
| 3. | During the reaction of boron -diiminates with HCl or HBF4, boronium salts are formed with -diimines as ligands. |
3.
K. N. Makarov T. N. Abroskina Yu. A. Cheburkov I. L. Knunyants 《Russian Chemical Bulletin》1976,25(4):922-924
| 1. | The cesium chloride adducts with perfluoroacetone, 1-methyl-2-oxaperfluoroenanthyl fluoride, and perfluoroisobutylene react smoothly with symmetrical dichlorodimethyl ether, replacing both chlorine atoms, with the formation of the corresponding ethers. |
| 2. | The interaction of,-dihydroperfluoroamyl alcoholate with symmetrical dichlorodimethyl ether leads to the replacement of both chlorine atoms, with the formation of the corresponding ether. |
| 3. | The reaction of perfluoro-t-butylanion with tris(chloromethyl)amine leads to tris-(1,1-dihydro-perfluoroneopentyl) amine. |
| 4. | Perfluoro-t-butylanion replaces only one chlorine atom in the molecule of unsymmetrical di-chlorodimethyl ether, forming-chloro- -perfluoro-t-butyldimethyl ether. |
4.
| 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. |
5.
V. A. Ermolaeva G. A. Marchenko V. I. Markovskii V. I. Slovetskii S. S. Novikov 《Russian Chemical Bulletin》1976,25(12):2495-2498
| 1. | Study has been made of the IR spectra of N--polynitroalkylhydrazine derivatives, band assignments being made for stretching vibrations in the NH, C=O, and NO2 groups. |
| 2. | Integral intensities for NO2 antisymmetrical stretching absorption bands are additive. Splitting of these bands is characteristic of nitro compounds containing a hydrazine radical in the -position with respect to the nitro group. |
| 3. | It has been shown that intermolecular hydrogen bonding exists in the N--polynitro-alkylhydrazines, in the crystalline state and in concentrated solution. |
6.
P. P. Levin V. A. Kuz'min V. B. Ivanov V. V. Selikhov 《Russian Chemical Bulletin》1988,37(8):1552-1555
| 1. | Data on the kinetics of geminal and bulk recombination of radical pairs formed in transfer of a hydrogen atom from 2,4,6-trimethylphenol to the triplet state of benzophenone in polyvinyl chloride films were obtained with the method of laser photolysis. |
| 2. | Bulk recombinatin of low-molecular-weight radicals makes the fundamental contribution to the kinetics of their quenching in films containing 50% liquid plasticizer and is characterized by high values of the second-order rate constants, close to the value of the rate constant of a diffusion-controlled reaction in low-viscosity liquids. |
| 3. | Geminal recombination of low-molecular-weight radicals in polyvinyl chloride films is characterized by polychromatic kinetics and makes a marked contribution with a concentration of plasticizer 60%. |
7.
| 1. | It has been shown that bifunctional agents have high activity in catalyzing -elimination reactions; study has been made of the effect of the concentration of such agents on the specific rate of -elimination from methyl-substituted ethoxy--ketoesters. |
| 2. | Study has been made of the state of 2- and 3-oxypyridines in benzene solution at 80°C. A value has been obtained for the 2-oxypyridine dimerization constant. |
| 3. | A mechanism has been proposed for the action of 2-oxypyridine in catalyzing -elimination reactions, and equilibrium constants and rate constants calculated for the various mechanism steps. The factors responsible for the low catalytic activity of 8-oxyquinoline are discussed. |
8.
L. A. Rozov Yu. V. Zeifman N. P. Gambaryan Yu. A. Cheburkov I. L. Knunyants 《Russian Chemical Bulletin》1976,25(12):2560-2566
| 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. |
9.
A. P. Brestkin I. L. Brik L. I. Ginetsinskaya N. N. Godovikov M. I. Kabachnik E. G. Kireeva S. A. Trifonova 《Russian Chemical Bulletin》1976,25(4):861-864
| 1. | O,O-Diisopropyl-, O,O-dipropyl, and O,O-dibutyl-S-(-N, N-cyclohexy]methylaminoethyl)thiophosphates and their methiodides were synthesized and their anticholinesterase activity was determined in relation to butyrylcholinesterase from horse blood serum and acetylcholinesterase from human erythrocytes. |
| 2. | O,O-Diisopropyl-S-(-N, N-cyclohexylmethylammoethyl)thiophosphate and its methiodide display the largest effect of selective effect in relation to butyrylcholinesterase. |
10.
| 1. | In the nucleophilic addition of alcohols to alkylacetylenes (methyl- and tert-butyl-), the regiospecificity of the attack of alkoxide converts to regiose lectivity with the increasing steric requirements of the substituent in the alkyne and of the attacking nucleophile. |
| 2. | The reaction leading to the adduct takes place with strict steric specificity by a nucleophilic mechanism of 1, 2-anti-addition with the formation of cis isomers; this behavior is independent of steric hindrances. |
11.
K. K. Babievskii I. M. Filatova V. M. Belikov L. I. Makhnova R. I. Pomilenko É. P. Sapozhnikova V. I. Sveklova 《Russian Chemical Bulletin》1976,25(12):2549-2553
| 1. | The reaction of -nitrocinnamic esters with methanol proceeds at room temperature and in the absence of base; the addition of acetic acid sharply retards the rate of the addition reaction. |
| 2. | The introduction into the -position of -nitroacryl esters of radicals containing an unshared pair of electrons on the nitrogen (3-indolyl, anilino, dimethylamino) depresses the electrophilic character of the C=C bond in these compounds, and they do not react with alcohols under analogous conditions. |
| 3. | N-Acylated -nitrovinylindole is deacylated under mild conditions under the action of alcohols. |
12.
A. I. Kokorin L. S. Bogach A. B. Shapiro É. G. Rozantsev 《Russian Chemical Bulletin》1976,25(9):1874-1878
| 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. |
13.
| 1. | An x-ray diffraction structural analysis has established the structure of the merocyanine form of 1-hydroxyethyl-3,3-dimethyl-6-nitro-8-methoxyspiro(indoline-2,2-[2H-1]-benzopyran). The introduction of an 8-OCH3 substituent into the benzopyran fragment reduces the zwitter-ionic nature of its complex hybrid structure and increases the contribution of the less polar quinoid form, leading to increased stability of the photochromic systems derived from this type of spiropyrans relative to side-reactions. |
| 2. | The molecules in this crystal structure form strong chains due to Van der Waals interactions, which are linked by hydrogen bonds. The formation of such chains and their mutual association largely determines the structure of the absorption spectra of this compound in the solid phase and solution. |
14.
T. V. Troepol'skaya G. A. Vagina V. I. Morozov Yu. P. Kitaev 《Russian Chemical Bulletin》1988,37(6):1115-1120
| 1. | The degree of oxidation of the metal ion in the chelates of Co, Pd, and Cu with -hydroxylamine oximes is 2+ according to electrochemial and EPR data. |
| 2. | In the first stage of the electroreduction of the investigated chelates of Co with nioxime and of Cu with -hydroxylamine oxime the degree of oxidation of the metal ion in the complex changes, while in the case of the other compounds the first electrons are probably accepted by mixed molecular orbitals, to which the ligand fragment makes the largest contribution. |
| 3. | The electrode reactions of the Co(II) and Pd(II) chelates with -hydroxylamine oximes are complicated by the catalytic evolution of hydrogen from solutions containing proton donors. |
15.
Zh. A. Krasnaya T. S. Stytsenko V. S. Bogdanov A. S. Dvornikov 《Russian Chemical Bulletin》1989,38(6):1206-1218
| 1. | Dienic-dimethylaminocarbonyl compounds were synthesized containing a Br, OEt, or CN substituent in the -position.-Dimethylamino--cyanodienones are found in the open form and do not cyclize to 2H-pyrans. |
| 2. | The existence of a dynamic equilibrium was established between-dimethylamino--bromodienone (or-dimethylamino--ethoxydienone) and 3-bromo-2-dimethylaminopyran (or 3-ethoxy-2-dimethylaminopyran), which depends on the solvent and temperature. |
| 3. | The equilibrium is shifted toward the 2H-pyran with increasing bulk of the solvent in the -position of the-dimethylaminodienone. |
| 4. | The 2H-pyrans upon the action of UV light undergo reversible dissociation of the C-O bond and isomerize to-aminodienones. |
16.
B. V. Lebedev T. A. Bykova E. G. Kiparisova Ts. M. Frenkel' A. M. Fainleib V. A. Pankratov 《Russian Chemical Bulletin》1988,37(6):1082-1086
| 1. | The temperature dependence of the heat capacity of phenyl glycidyl ether in vitreous, crystalline, supercooled liquid and liquid states was studied in an adiabatic vacuum calorimeter in the 14–330K range with an error of -0.3 %. The temperature, enthalpy and entropy of fusion, as well the glass transition temperature were determined. |
| 2. | The thermodynamic functions H(T)-H(O), S(T), G(T)-H(O) were calculated for the range of 0–330 K; the zero entropy and the difference between the zero enthalpies of a vitreous and crystalline phenyl glycidyl ether were calculated; the thermodynamic parameters of its formation at a standard pressure and T=298.15 K were calculated. |
| 3. | The enthalpy, entropy, and Gibbs energy of the reaction of phenyl glycidyl ether with diphenylcarbodiimide and phenylisocyanate were calculated. It was found that these processes are thermodynamically permissible over the whole temperature range studied and have an upper limiting temperature. |
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.
Z. V. Todres G. Ts. Ovsepyan E. A. Ionina A. Yu. Kosnikov S. V. Lindeman Yu. T. Struchkov 《Russian Chemical Bulletin》1988,37(8):1651-1656
| 1. | o-Dinitrobenzene dianion reacts with p-dimethylaminobenzenediazonium cation to give 2-nitro-4-dimethylaminoazobenzene. |
| 2. | o-Dinitrobenzene anion-radical reacts with benzenediazonium cations bearing a dimethylamino-or nitro-group in the para-position, to give 3-nitro-4-hydroxy-4-dimethylamino-azobenzene and 3,4-dinitro-4-hydroxyazobenzene respectively. |
| 3. | In the case of the 4-methoxybenzenediazonium cation, reaction with the o-dinitrobenzene anion-radical affords 4-methoxy-3-(2-nitrophenyl--azoxy)-4-hydroxyazobenzene, the structure of which has been established by x-ray diffraction analysis. |
| 4. | These azo-compounds are formed in solvents which favor the stability of ion pairs of the dianion or anion-radical of o-dinitrobenzene with potassium cations. Dissociation of the ion pairs results in the occurrence of electron transfer only. |
19.
| 1. | The structure of the isocyanate functional group in organic isocyanates in the crystalline state is analogous to that in the gas phase. |
| 2. | The isocyanate group (H)C1-N=C2=O exists in a trans conformation in all three of the isocyanates studied. |
| 3. | The lamellar packing characteristic of ,-naphthalenediisocyanate molecules may be assigned to a structural subclass of naphthalene ¯1, namely, P(x)P21/b. |
20.
V. I. Kadentsev B. I. Maksimova O. S. Chizhov L. A. Yanovskaya 《Russian Chemical Bulletin》1989,38(4):874-876
| 1. | The -lactone is more stable than the -lactone both relative to electron impact and upon chemical ionization. |
| 2. | The major pathways for fragmentation upon electron impact for the -lactone are related to decomposition of the cyclohexane ring, while, in the case of -lactone, fragmentation of the oxygen-containing part of the molecule also occurs in addition to these processes. |