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1.
V. K. Mavrodiev I. I. Furlei E. A. Burmistrov F. Z. Galin S. N. Lakeev V. K. Ignatyuk G. A. Tolstikov 《Russian Chemical Bulletin》1989,38(3):507-511
| 1. | The stability of MNI of substituted spiro[cyclopropan-1,1-indene]-2-carboxylates is increased with increasing -system and introduction of electron acceptor substituents. The fragmentation of MNI is related to loss of substituents and is accompanied by opening of the cyclopropane ring. |
| 2. | The average lifetime of (M-R1,2) ions is measured relative to dissociation with elimination of a molecule of ethanol. |
2.
| 1. | It has been shown by PMR spectroscopy that in a solution of RYbI there exists an equilibrium similar to that established by Schenk for Grignard reagents. |
| 2. | The compound formed by the action of an equimolar mixture of PhI and LiI on Yb metal in THF differs in reactivity from PhYbI in its reaction with CF2=CF2. |
| 3. | The reaction of PhSmI with 1,2,2-trifluorostyrene differs from the reactions of PhEuI and PhYbI in that it gives an equimolar mixture of the cis and trans isomers of 5,6-difluoro-4,6-diphenyl-5-hexene-1-ol. |
| 4. | PHCeI does not react with 1,2,2-trifluorostyrene. However, the organocerium complex formed by the oxidatlve addition of Ce to PhI in the presence of an equivalent quantity of LiI reacts with 1,2,2-trifluorostyrene to form an equimolar mixture of the cis and trans isomers of 5.6-difluoro-4,6-diphenyl-5-hexene-1-ol. |
3.
| 1. | Indium atoms have been obtained in aqueous solutions of univalent indium by pulse radiolysis. |
| 2. | In0 reacts with In+ to form the dimer In 2 + . |
| 3. | The optical characteristics of these particles, the rate constants for their formation and loss, as well as the oxidation-reduction potentials have been determined. |
4.
Mirzayanova M. N. Medvedeva I. V. Fedulova I. E. Egorov Ts. A. Khorlin A. Ya. 《Russian Chemical Bulletin》1976,25(7):1520-1524
| 1. | The synthesis has been accomplished of the methylamides of-N-benzoyl--(N-methyl-N-phenyl-thiocarbamyl)propionic ] and butyric acids, which under the conditions used for dehydration of polypeptide chains by the Edman method through treatment with trifluoroacetic acid were converted into cyclic derivatives of hexahydropyrimidine. |
| 2. | Derivatives of D, L-erythro- and D, L-threo-diaminobutyric acid were readily and reversibly converted into one another under the action of acidic and basic reagents. |
5.
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. |
6.
| 1. | The corresponding 1,3-bis[-(p-toluenesulfonamido)alkyl]uracils are formed as a result of the reaction of 1, 3-bis(-bromoalkyl)uracils and the Na salt of p-toluenesulfamide. |
| 2. | Interaction of l-(-bromobutyl)uracil with p-toluenesulfamide in a medium of n-butanol leads to formation of 9,18,19,20-tetraoxo-1,6,10,15-tetraazatricyclo[13.3.1.16.10]-eicosa-7, I6-diene,l-(-hydroxybutyl)-2-butoxypyrimid-4-one, and l-(-hydroxybutyl)-2-p-toluenesulfonamidopyrimid-4-one. |
7.
| 1. | Using seven independent methods it was found that the concentration of the active centers on the surface of-Al2O3, which are responsible for the dehydration, is (9±1)×1017 centers/m2. The catalytically active centers are identical with adsorption centers. |
| 2. | A method of calculating the stochiometry, concentration, and thermodynamics of the surface association reactions has been developed. |
| 3. | The first reaction step proceeds according to the associative bimolecular substitution mechanism, with the formation of an associative intermediate compound. The association enthalpy and entropy have been calculated. |
8.
| 1. | The authors have studied the formation of electron and hole paramagnetic centers in gamma-irradiated magnesium hydroxide and oxide with various degrees of dehydration. |
| 2. | Rise in the temperature of preliminary heat treatment of the magnesium oxide causes an increase in the radiation-chemical yield of FS + centers and a decrease in that of V su – centers. |
| 3. | The thermal stability of paramagnetic centers in magnesium oxide increases as the hydroxyl group content decreases. |
9.
Evgeny V. Shulishov Olga A. Pantyukh Leonid G. Menchikov Yury V. Tomilov 《Tetrahedron letters》2019,60(31):2043-2045
Catalytic cyclopropanation of spiro[2.4]hepta-4,6-diene with diazomethane in the presence of copper or palladium compounds results in mono- and dicyclopropanation products, namely, spiro[bicyclo[3.1.0]hex-3-ene-2,1′-cyclopropane] and spiro[cyclopropane-1,5′-tricyclo[4.1.0.02,4]heptane], with different efficiency. The use of Pd compounds as catalysts allows the cyclopropanation to be performed under conditions of simultaneous generation and decomposition of diazomethane. 相似文献
10.
V. T. Varlamov 《Russian Chemical Bulletin》1989,38(3):482-490
| 1. | Secondary aromatic amines are catalysts in the reaction of sterically hindered aroxyl radicals with hydroperoxides. The rate of the catalytic reaction v is proportional to [ArO], [ROOH], [AmH], and inversely proportional to [ArOH]. |
| 2. | Values of kcat have been found for eleven aromatic amines in reaction with 2,4,6-tri-t-butylphenoxyl radical with cumyl hydroperoxide in CCl4 over the temperature range 298,2–341.6 K. The values of E and F fall with increasing electron-donor properties of the substituents on the aromatic ring of the amine. On the basis of the values of k which were obtained, several parameters have been estimated including the strength of the N-H bond in the amine molecule. |
| 3. | For diphenylamines with electron-donor substituents there is a linear relationship between log k and the + function. |
11.
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. |
12.
| 1. | 1,2-Oxathiolan-5-one-2-oxides are readily cleaved by nucleophiles (H2O, ROH, HNR2) under mild conditions at the O-CO bond only, with the formation of the -(hydroxysulfinyl)-alkanoic acid derivatives. |
| 2. | 2,1-Benzoxathiol-3-one-1-oxide is cleaved by alcohols at both the O-CO and the O-SO bonds to give the unstable monoesters at the carboxyl and sulfinyl groups. |
| 3. | Unlike 2,1-benzoxathiol-3-one-1-oxide, 1,2-oxathiolan-5-one-2-oxides on boiling with excess alcohols give -(hydroxysulfinyl)alkanoic acid bisesters. |
13.
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. |
14.
V. Z. Sharf L. D. Panfilova N. V. Borunova N. V. Antseva L. P. Karapetyan P. G. Antonov K. M. Saldadze 《Russian Chemical Bulletin》1989,38(4):695-698
| 1. | New catalysts, Pd-Sn compounds, were synthesized and fixed to macroporous anion exchangers. They are active in hydrogenation and isomerization reactions of 1-hexene. |
| 2. | The catalytic properties of the Pd-Sn systems depends on the structure of the fixed compound (cluster, complex), the nature and state of the exchanger functional groups (Cl-or OH-form), and the reaction conditions (pH, PH2). |
| 3. | The cluster [Pd4(SnCl2)2(SnCl3)8]5– on the highly basic anion exchanger AV-17-2P (Cl-form) catalyzes mainly the hydrogenation reaction, while the complex [Pd(SnCl3)4]2– catalyzes the isomerization reaction. |
| 4. | The complex [Pd(SnCl3 4)]2–, fixed to the weakly basic anion exchanger AN-221 (OH-form), is active in the isomerization and hydrogenation of 1-hexene under mild conditions. |
15.
I. V. Anonimova N. A. Chadaeva L. K. Yuldasheva S. G. Vul'fson A. N. Vereshchagin B. A. Arbuzov 《Russian Chemical Bulletin》1976,25(12):2519-2524
| 1. | It has been shown that 2-bromo-l,3,2-dioxaarsenanes exist in chair conformation with axially oriented As-Br bonds. |
| 2. | Polarity and polarizability parameters have been found for the As-O and As-Br bonds in 2-bromo-l,3,2-dioxaarsenanes. |
| 3. | The so-called -effect is stronger in the O2AsBr group than in the O2AsCl group. |
16.
| 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. |
17.
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. |
18.
R. A. Fridman G. A. Kliger E. I. Bogolepova Yu. V. Maksimov I. P. Suzdalev 《Russian Chemical Bulletin》1976,25(4):726-729
| 1. | The catalytic properties of iron nitride (Fe2N) and carbonitride (Fe2C0.29N0.71) in the reactions of amination and dehydrogenation of alcohols were compared. |
| 2. | In the course of the amination and dehydrogenation reactions on a nitride catalyst, there is an elution of part of the introduced nitrogen from the surface with the formation of the structure of the lower nitride. |
| 3. | For related structures of the nitride and carbonitride, a correlation was detected between the catalytic activity and the average magnetic moment of the iron atom in the alloy. |
19.
G. N. Nikonov A. S. Balueva A. A. Karasik I. A. Litvinov O. A. Erastov B. A. Arbuzov V. A. Nauraov 《Russian Chemical Bulletin》1988,37(1):143-147
| 1. | Reactions of ammonium 2,2,5-triphenyl-1,3,2,5-dioxaborataphosphorinanes with alkyl halides, diphenylchlorophosphine, formaldehyde, and ethylene oxide were carried out. |
| 2. | The molecular structure of the N--hydroxyethyltriethylammonium salt of 2,2,5-tri-phenyl-4,6-dimethyl-1, 3,2,5-dioxaborataphosphorinane was established. |
20.
| 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. |