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1.
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. |
2.
Z. N. Parnes G. D. Kolemnikova M. I. Kalinkin D. Kh. Shaapuni S. M. Markosyan D. I. Kursanov 《Russian Chemical Bulletin》1976,25(11):2333-2335
| 1. | Platinum hydrides are the active donors of the hydride ion with respect to Ph3 \mathop C? Ph_3 \mathop C\limits^ \oplus . |
| 2. | The phosphine complexes of Ni, Pd, and Pt exhibit catalytic activity in the ionic hydrogenolysis of alcohols, the Pt complexes being the most active. |
3.
L. S. Isaeva G. I. Drogunova A. S. Peregudov D. N. Kravtsov 《Russian Chemical Bulletin》1988,37(1):153-157
| 1. | New cationic o-tolyl and o-fluorophenyl complexes of Ni containing Ph3P, MeCN, or THF ligands have been synthesized. |
| 2. | Reaction of these compounds with potassium carboxylates gave the novel o-tolyl and o-fluorophenylbis(triphenylphosphinyl)nickel carboxylates. |
| 3. | According to19F NMR data o-tolylbis(triphenylphosphinyl)nickel p-fluorobetizoate contained a highly polarized Ni-O bond. |
4.
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. |
5.
| 1. | The complexes of Pd(acac)2 and Pd(OAc)2 with triphenylphosphine catalyze the telomerization of isoprene with water in the presence of CO2, which leads to the formation of isomeric dimethyloctadienols. |
| 2. | The complexes of Pd(acac)2 and Pd(OAc)2 with tricresyl phosphite catalyze the formation of the isomeric dimethyloctadienol acetates from isoprene and CH3COOH. |
| 3. | In acetone the complexes of Pd(acac)2, Pd(OAc)2 with triphenylphosphine smoothly and almost completely dimerize isoprene to 2,7-dimethyl-1,3,7-octatriene. |
6.
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. |
7.
A. I. Kokorin A. N. Astanina V. D. Kopylova E. L. Frumkina T. A. Sazykina 《Russian Chemical Bulletin》1989,38(7):1362-1365
| 1. | Kinetic investigations and EPR spectroscopy have shown that in the oxidation of n-butyl mercaptan with molecular oxygen in the presence of Cu(AN-251) complexes the more coordination-saturated structures (with respect to nitrogen) show the higher catalytic activity. |
| 2. | By varying the presorption treatment (protonation of the functional groups of the ion exchanger) and the content of Cu(II) ions one can change the composition and structure of the polymer-metal complexes, thus influencing their catalytic activity. |
8.
D. B. Furman A. V. Kudryashev A. O. Ivanov L. S. Isaeva L. N. Morozova T. A. Peganova D. N. Kravtsov O. V. Bragin 《Russian Chemical Bulletin》1988,37(7):1408-1411
| 1. | It has been shown that in the presence of (2-methylenecyclopropane)bis(triphenyl-phosphine) nickel (Kt-1) and of a series of triphenylphosphine Ni(O) complexes the catalytic conversion of methylenecyclopropane (MCP) proceeds with the formation of identical di- and trimerization products. It is postulated that the mechanism of di- and trimerization of MCP on all Ni(O) phosphine complexes is similar, with the formation of Kt-1 as a general intermediate. |
| 2. | Complexes of Ni(I) and Ni(II) which have been studied were found to be inactive in MCP conversion. |
9.
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. |
10.
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. |
11.
In conclusion, let us note the principal results of the calculation.
Institute of Catalysis, Siberian Branch, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 2, pp. 35–41, March-April, 1992. 相似文献
| 1. | On a clean Ni(100) surface, only molecular adsorption of water is realized. Partial dissociation of H2O is thermodynamically allowed process; however, dissociation of water is impossible because of kinetic limitations. |
| 2. | Modification of the nickel surface by oxygen stabilizes the donor-acceptor pair (H2O/O) on the surface and removes the kinetic limitation in decomposition of water, through a substantial reduction of the activation energy of dissociation. |
| 3. | The promoting role of oxygen is manifested in an increase in the nonuniformity of electron density on the nickel surface in the vicinity of the [Ni]–OH2 bond, which makes it possible to open up a new channel of the reaction in which a high degree of energy compensation in the water dissociation reaction is possible. |
12.
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. |
13.
M. V. Evstiferov N. G. Vanifatova O. M. Petrukhin A. I. Kokorin V. A. Reznikov L. B. Volodarskii 《Russian Chemical Bulletin》1989,38(5):921-926
| 1. | The low-spin Ni(II) ion in the square planar spin-labeled -dioximate NiL2 effectively exchanges spin density between the groups of the ligands. |
| 2. | Stepwise adduct formation NiL2 NiL2B NiL2B2 in the Ni-HL-toluene-neutral electron-donor compound system is observed and studied. Adduct formation is found to lead to a decrease of the value of the spin exchange integral ¦j¦ as a result of a decrease of the degree of covalency of the Ni bond with the ligand donor atoms in the equatorial plane. |
14.
D. B. Furman A. O. Ivanov A. V. Kudryashev L. N. Morozova T. A. Peganova P. V. Petrovskii L. S. Isaeva D. N. Kravtsov O. V. Bragin 《Russian Chemical Bulletin》1989,38(5):892-895
| 1. | The formation of (2-methylenecyclopropane)bis(triphenylphosphine)nickel was established in the reaction of methylenecyclopropane (MCP) with Ni(PPh3)3, Ni(PPh3)4, and the catalyst (Cat) obtained by the reduction of NiCl2·6H2O by sodium borohydride in the presence of PPh3. |
| 2. | 31P-{1H} NMR spectroscopy was used to determine that the catalyst was composed of Ni(PPh3)3, Ni(PPh3)4, and, probably, Ni(PPh3)2. |
| 3. | Interconversions of the catalyst and (2-methylenecyclopropane)bis(triphenylphosphine)nickel were determined during the transformations of MCP, which supports the scheme for the catalytic cycle of MCP reactions by the action of Ni(O) triphenylphosphine complexes. |
15.
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. |
16.
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. |
17.
| 1. | A series of C-functional derivatives of (3)-1,2-dicarbaundecaborate was synthesized and some of their properties were studied. |
| 2. | Apparent ionization constants of acids of the (3)-1,2-dicarbaundecaborate series were measured and it was found that they are very weak carboxylic acids. |
| 3. | Upon reaction with excess LiA1H4, under mild conditions the carbonyl, *20c \CH(OH) / \begin{array}{*{20}c} \backslash \\ {CH(OH)} \\ / \\ \end{array} , and CH2OH groups of dicarbaundecaborate ketones and alcohols are reduced to CH2 and CH3 groups, respectively. |
| 4. | The effect of Grignard reagent on ketones and esters of the dicarbaundecarbprate series was studied and it was established that the composition of reaction products depends both on the steric hindrance of the carbonyl group and on the electron-donating effect of the (3)-1,2-dicarbaundecaborate substituent. |
18.
| 1. | A practicable method for the synthesis of vicinal bis(difluoramino)-containing carboxylic acids by reacting tetrafluorohydrazine with unsaturated acids has been developed. |
| 2. | ,-Bis(difluoramino)carboxylic acids are unstable and undergo decarboxylation followed by dehydrofluorination. |
| 3. | ,-Bis(difluoramino)carboxylic acids are fairly stable and in some cases display the properties of ordinary carboxylic acids. |
19.
| 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. |
20.
V. I. Avdeev I. I. Zakharov G. M. Zhidomirov N. M. Neshev E. I. Proinov 《Journal of Structural Chemistry》1992,33(2):179-185
| 1. | Upon interaction of OH with Ni(100)m Ni(111), and Ni(110), stable, many-center forms of OH adsorption are produced. One-center and bridge forms of OH adsorption on nickel are kinetically unstable for the lowest surface coverages. |
| 2. | On Ni(100) and Ni(111), a linear form of adsorption of OH is realized; on Ni(110), an angular form is realized, with a polar angle 0 = 20°. |
| 3. | In the course of adsorption, there is a significant transfer of electron density from the metal to the OH, leading to an increase in the work function of the electrons and a decrease in the frequency of the (O–H) vibration. For the angular forms of adsorption, bending vibrations (O–H–Ni) are active. |
| 4. | Upon adsorption of OH, a strong -bond Ni(110)–OH is formed, as manifested in the UV photoelectron spectra by absorption in the 9.2 eV energy region. |