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1.
N. E. Dontsova V. P. Sergeeva E. N. Prilezhaeva V. S. Bogdanov 《Russian Chemical Bulletin》1989,38(3):575-578
| 1. | We have found that, in the process of nucleophilic substitution of vinyls with ionic and nonionic nucleophiles, the reactivity of tris(organosulfonyl)chloroethenes is considerably greater than that for tetrakis(organosulfonyl)ethenes, and, particularly, for 1,2-di(organosulfonyl)-1,2-dichloroethenes. |
| 2. | We have discovered multiple reaction pathways for substitution in tris(organo-sulfonyl) chloroethene, combined with the presence in the molecule of two other nucleophiles (RSO2, Cl). We have demonstrated that, under weak nucleophilic conditions, substitution of the RSO2-group is preferred. |
2.
I. E. Chlenov I. M. Petrova V. M. Shitkin V. A. Tartakovskii 《Russian Chemical Bulletin》1976,25(6):1347-1350
| 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. |
3.
K. A. Andrianov M. M. Il'in V. N. Talanov I. I. Zhurakovskaya 《Russian Chemical Bulletin》1976,25(11):2432-2435
| 1. | The coammonolysis of SiCl4 and Me3SiCl leads to a mixture of tris(trimethylsilylamino)silylamine (I), tetrakis(trimethylsilylamino)silane (II), and also cyclodi- and cyclotrisilazanes. |
| 2. | Additional treatment of the mixture with Me3SiCl increases the yield of (II). |
4.
L. G. Vorontsova V. M. Shitkin O. S. Chizhov I. M. Petrova I. E. Chlenov V. A. Tartakovskii 《Russian Chemical Bulletin》1976,25(4):790-794
| 1. | We have determined the confirmations and accurate geometrical parameters for the two isomers of 8-p-bromophenyl-6-cyano-2,9-dioxa-1-azabicyclo[4.3.0]nonane. |
| 2. | Replacement of the nitro group by the cyano group proceeds mainly with inversion of configuration at the center of substitution. |
5.
R. I. Khusnutdinov V. A. Dokichev D. K. Galeev N. F. Asylguzhina S. Z. Sultanov U. M. Dzhemilev 《Russian Chemical Bulletin》1988,37(9):1932-1935
| 1. | Catalytic dimerization of spiro[2.4]hepta-4,6-diene (I) into dispirocyclopropan-5,1'-endotricyclo [5.2.1.02,6]deca-3,8-dien-10,1-cyclopropane (II) was carried out. |
| 2. | It was established that [Rh(CO)2Cl]2 catalyzes transformation of dispirocyclopropan-6,1'-pentacyclo [5.3.0.02,5.03,9.04,8]-decan-10,1-cyclopropane (XI) into the dimer spiro[2.4]hepta-4,6-diene (II). |
| 3. | Upon reduction of dispirocyclopropan-6,l'-pentacyclo[5.3.0.02,5.03,9.04.8]decan-<>-cyclopropane in the presence of PtO2 1,1,3,3-tetramethyl-1,3-bishomocubane is formed. |
| 4. | The possibility of synthesizing adamantane, diamantane, and their derivatives by skeletal isomerization of hydrocarbons obtained from spiro[2.4]hepta-4,6-diene has been shown. |
6.
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. |
7.
| 1. | The conformation and geometric parameters of isomeric macrocyclic ketolactones including a thiophene ring have been determined: 5-oxa-[10]--cyclothienedione-1,4 (I) and 6-oxa-[10]--cyclothienedione-1,5(II). |
| 2. | The position of the lactone group in the ansa-compound (II) leads to a less stressed macrocycle, in comparison with (I). |
8.
| 1. | Using DMSO and MeSOPh it has been shown for the first time that O-trifluoroacetylated sulfoxides react with unactivated trisubstituted olefins to give allylsulfonium salts. |
| 2. | LiClO4 has been found to accelerate this ene-type reaction. |
| 3. | It has been found for the first time in the aliphatic series that the competition between [3, 2]-rearrangement and the Stevens rearrangement of the S-ylid generated from the allylsulfonium salt is governed by the type of counterion present, and this observation has been rationalized. |
9.
| 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. |
10.
Vol'pin M. E. Savitskii A. V. Novodarova G. N. Kolosova E. M. 《Russian Chemical Bulletin》1976,25(7):1430-1434
| 1. | The chelate cobalt complex Co(II)N, N-bis(salicylidene)ethylenediamine [Co(Salen)] is an effective catalyst for NAD-H oxidation in methanol at room temperature. |
| 2. | The rate of oxidation is closely dependent on the structure of the complex catalyst and the composition of the solvent. |
| 3. | The mechanism of Co(Salen) complex catalytic activity in NAD-H autooxidation is discussed in terms of three proposed reaction schemes. |
11.
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. |
12.
N. D. Chkanikov V. L. Vershinin M. V. Galakhov A. F. Kolomiets A. V. Fokin 《Russian Chemical Bulletin》1989,38(1):113-119
| 1. | Nonsterically hindered primary arylamines react with hexafluoroacetone benzenesulfonyl- and trifluoroacetylimines to give stable gem-diamino compounds. |
| 2. | The presence of substituents at the nitrogen of the arylamine destabilizes these gem-diamino compounds, with the formation of C2- and C4-alkylation products. With hexafluoroacetone trifluoroacetylimine, C2-alkylation is accompanied by heterocyclization to give 1-substituted 2,4,4-tris(trifluoroacetyl)-1,4-dihydroquinazolines. |
| 3. | N,N-Dialkylanilines are regioselectively alkylated at C4. |
13.
| 1. | Fragmentation has been studied, and kinetic parameters calculated, for quasimolecular [M+H]+ ion breakdown under chemical ionization in methyl ethers of the desoxyglycosides. |
| 2. | Alteration of the position of the desoxy link in the glycoside molecule brings about an extensive redistribution of fragment ion peak intensities of the CI mass spectra of the desoxyglycosides, with an appreciable alteration in the rate of quasimolecular ion breakdown in the gaseous phase. |
14.
V. N. Nesterov L. A. Rodinovskaya V. P. Litvinov Yu. A. Sharanin A. M. Shestopalov V. Yu. Mortikov V. I. Shvedov V. E. Shklover Yu. T. Struchkov 《Russian Chemical Bulletin》1988,37(1):129-134
| 1. | Condensation of the sodium salts of 3-aryl-1-hydroxypropene-1-ones-3 with cyanoace-tamide proceeds regioselectively with the formation of 6-aryl-3-cyanopyridine-2(1H)-thiones which are used in the synthesis of thieno[2,3-b]pyridine and thiazolo[3,2-a]pyridinium cations. |
| 2. | The structure of 2,2-bis[6-(2,4-dimethoxyphenyl)-3-cyanopyridine-2] disulfide has been established unequivocally by an x-ray diffraction study. The molecule is structured from two approximately planar fragments joined by a disulfide bridge with CSSC torsion angle = 83.5(2)° and S-S bond length=2.015(1) Å. |
15.
N. N. Makarova B. D. Lavrukhin G. N. Turkel'taub N. N. Kuz'min I. M. Petrova E. V. Matukhina 《Russian Chemical Bulletin》1989,38(6):1234-1240
| 1. | The stepwise condensation of ethylchlorosilane with diethylsilanediol and 1,3-dihy-droxytetraethyldisiloxane was used to obtain 2,6- and 2,8-dichloroethylcyclotetra (penta, hexa) siloxanes. It was established that the reaction is accompanied by intramolecular cyclization in the reaction with 1,3-dihydroxytetraethyldisiloxane: in the first step with the formation of chloropentaethylcyclotrisiloxane and in the second step with the formation of 2,8-dichlorodecaethylcyclohexasiloxane and its structural isomer. |
| 2. | An increased tendency to form ethylbicyclo [3.5.1]penta- and ethylbicyclo[5.5.1]-hexasiloxane was observed in the hydrolysis of 2,6-dichlorooctaethylcyclopenta- and 2,8-dichlorodecaethylcyclohexasiloxanes. |
16.
B. E. Ivanov L. A. Valitova V. I. Gaidai T. G. Bykova N. I. Kuchma S. V. Samurina 《Russian Chemical Bulletin》1976,25(11):2386-2389
| 1. | An intermediate alkoxyphosphorane with two pentacoordinated phosphorus atoms was isolated and characterized during the reaction of 2,5-bis(diethylaminomethyl)hydroquinone with trialkyl phosphites. |
| 2. | A method has been developed for the synthesis of phosphorylated dihydric phenols. |
| 3. | The triethylether of 3-ethoxy-6-hydroxy-1,4-xylyenediphosphonic acid was prepared by the interaction of 2,5-bis(diethylaminomethyl)hydroquinone with diethylphosphorous acid in the presence of triethyl phosphite. |
17.
K. B. Yatsimirskii M. I. Kabachnik T. Ya. Medved' N. P. Nesterova É. I. Sinyavskaya L. V. Tsymbal F. I. Bel'skii 《Russian Chemical Bulletin》1988,37(1):44-49
| 1. | Stability constants for alkali metal complexes of composition [ML]+ and a copper complex [CuLCl]+, which are formed via treatment of alkali metal 2,4-dinitrophenolate or copper chloride with a series of carbamoyl phosphine oxide derivatives, have been determined in anhydrous solutions. |
| 2. | The most stable complexes are formed by ligands containing an aryl substituent attached to the phosphorus atom. |
18.
Lagerge S. Kamyshny A. Magdassi S. Partyka S. 《Journal of Thermal Analysis and Calorimetry》2003,71(1):291-310
A new batch titration microcalorimeter has been used for estimation of thermodynamic properties in various investigated colloidal systems. As examples, we present enthalpic and kinetic data obtained from this calorimetric device for four different processes widely encountered in colloid science:
This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
| (i) | The dilution/micellization process of cationic gemini surfactants in aqueous solution. |
| (ii) | The hydration process of non ionic surfactants in organic solution, i.e. the mechanism of micellar solubilization of water in the aggregates. |
| (iii) | The complexation of calcium ions by polyacrylates sodium salts (PaNa). |
| (iv) | The adsorption phenomenon of PaNa molecules on the calcium carbonate surface. |
19.
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. |
20.
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. |