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1.
F. M. Stoyanovich G. B. Chermanova Ya. L. Gol'dfarb R. G. Karpenko 《Russian Chemical Bulletin》1976,25(7):1503-1508
| 1. | p-Bis(tert-butylsulfonyl)benzene (I) and 2,5-bis(tert-butylsulfonyl)thiophene (II) when treated with n-BuLi are capable of replacing one of the sulfonyl groups by the n-butyl group. |
| 2. | The conditions were found where sulfone (II) is metalated in the position of the thiophene ring. |
| 3. | Lithium 2-thienyimercaptide is metalated in the free position. |
2.
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. |
3.
| 1. | We synthesized some new iminoxyl biradicals that contain bis(azamethine), bis(azamethine)-octatriene, bis(azamethine)phenylene, bis(azamethine)thiophene, and bis(azamethine)dithienyl sulfide bridges. |
| 2. | Intramolecular spin -spin exchange in iminoxyl biradicals can be accomplished via the bis(azamethine)octatriene, bis(azamethine)-1,4-phenylene, and bis(azamethine)-2,5-thiophene systems. |
| 3. | The degree of overlapping of the orbitals of the unpaired electrons in the new biradicals was estimated. |
4.
V. A. Mamedov I. A. Nuretdinov Yu. Ya. Efremov F. G. Sibgatullina 《Russian Chemical Bulletin》1989,38(4):867-869
| 1. | The reaction of esters of 3-phenyl-3-chloro-2-ketopropionic acid with sodium alcoholates in alcohol (methanol or ethanol) at reflux leads to the formation of an ester of 2,5-diketo-3,4-diphenyl-3-methoxyhexanedioic or 2,5-diketo-3,4-diphenyl-3-ethoxyhexanedioic acid. |
| 2. | The reactions of esters of 3-phenyl-3-chloro-2-ketopropionic acid with the corresponding sodium alcoholates in dilute solution at 0C give the product of the substitution of chlorine by an alkoxy group in quantitative yield. |
5.
V. V. Il'in A. Ch. -V. Kim A. V. Ignatenko V. A. Ponomarenko 《Russian Chemical Bulletin》1989,38(5):1083-1085
| 1. | The reaction of bis(N,N-dimethyl)terephthalamidine with imidates of perfluorohexanecarboxylic acid in diethyl ether gave 1,4-bis(2,4-perfluorohexyltriazinyl)benzene in high yield. |
| 2. | The reaction in methanol leads to the formation of fluorine-containing oligoarylenazomethines. |
6.
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. |
7.
| 1. | Substituted thiazoles are formed when N-acyl--aminoketones are heated with thioacetic acid and ZnCl2 in ether dioxane or ethyl acetate. |
| 2. | The reaction of acetamidoacetone with thioacetic acid and ZnCl2 at 20° leads to 2,5-dimethyl-5-acetylmercapto-2-thiazoline. |
| 3. | -Formamidoketones are formed when-aminoketone hydrochlorides are heated with orthoformic ester. |
8.
| 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. |
9.
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). |
10.
N. S. Vasileiskaya L. V. Gorbunova O. N. Mamysheva N. P. Makarenko G. N. Bortnikov 《Russian Chemical Bulletin》1976,25(12):2580-2584
| 1. | Oxidation of o-organosilyl-substituted phenols with potassium ferricyanide in an alkaline medium in an oxygen atmosphere led to the formation of siloxydiphenyls and bis(l-R2-3-R1-5-R3-2,5-cyclohexadien-4-one) peroxides. |
| 2. | The silyl-substituted peroxides were isolated preparatively. Their thermal decomposition occurred by a homolytic mechanism with cleavage of the O-O bond. |
11.
| 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. |
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%. |
13.
É. D. Filippova N. D. Mitrofanova L. I. Martynenko V. I. Spitsyn 《Russian Chemical Bulletin》1976,25(1):4-7
| 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. |
14.
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. |
15.
G. Grossman G. Komber G. Kroshvitts P. A. Kirpichnikov N. A. Mukmeneva D. G. Pobedimskii 《Russian Chemical Bulletin》1989,38(1):26-32
| 1. | Dithiophosphoric acids are either not catalysts or only act as moderate catalysts as a function of the structure in reactions of decomposition of CHP. |
| 2. | The real catalyst of decomposition of CHP in the presence of dithiophosphoric acids is the sulfuric acid formed during the oxidation of the dithiophosphoric acids, or the combination of the sulfuric acid with phosphours-containing acids. |
| 3. | Slow and fast stages of kinetic decomposition of CHP were detected, and the kinetic parameters of the fast stage were determined. |
16.
P. Ya. Bayushkin E. N. Gladyshev G. A. Razuvaev E. A. Emelina 《Russian Chemical Bulletin》1976,25(2):431-433
| 1. | The first stable compound with an O-Hg-Ge grouping was obtained by the reaction of 4,6-ditert-butyl-1,2-benzoquinone with bis(triisopropylgermyl)mercury. |
| 2. | A study was made of the photodecomposition of 1-triisopropylgermyloxy-2-triisopropylgermyl-mercuroxy-3,5-di-tert-butylbenzene, and also of its reaction with hydrochloric acid and ethylmercury chloride. |
17.
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. |
18.
G. A. Artamkina A. Yu. Mil'chenko I. P. Beletskaya O. A. Reutov 《Russian Chemical Bulletin》1988,37(12):2550-2556
| 1. | The kinetics of reactions of alkali metal salts of 9-carbomethoxy- and 9-cyanofluorene with para-nitrofluorobenzene and of Me3SnM with pentafluoropyridine have been studied. |
| 2. | In the case of carbanions the free anions are more reactive, while in the case of Me3SnM the corresponding tight (contact) ion pairs are more reactive. |
| 3. | The effect of the leaving group (on reactivity) was investigated using the reactions of pentafluorochlorobenzene with the K salts of 9-carbomethoxyfluorene and cyclopentadienylirondicarbonyl anions as examples. |
| 4. | The reaction mechanism has been shown to depend on the nature of the nucleophile. |
19.
A. K. Mal'tsev N. D. Kagramanov I. O. Bragilevskii N. G. Komalenkova S. A. Bashkirova D. A. Zagorets M. Ya. Kel'man E. A. Chernyshev O. M. Nefedov 《Russian Chemical Bulletin》1989,38(5):950-956
| 1. | Differences have been shown in the mass spectra of isomeric 1,1-difluoro- and 1,1-dichloro-1-silacyclopentenes, and also 1,1-dichloro-, 1,1-dihydro-, and 1,1-dideuterio-1-silacyclohexadienes, differences that make it possible to identify the isomers. |
| 2. | Mass spectrometry has been used to identify the intermediates formed in the vacuum pyrolysis of these silicon-containing cyclic compounds, and it has been established that all of the dihalo derivatives dissociate selectively, splitting off the corresponding dihalosilylene. |
| 3. | In the thermal dissociation of sila-2,5-cyclohexadiene, hydrogen splits off selectively from the silicon atom and one of the carbon atoms, forming silabenzene — a molecule with a multiple carbon-silicon bond. The mass spectrum of silabenzene has been obtained for the first time. |
20.
| 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. |