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1.
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. |
2.
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. |
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.
I. B. Kovaleva N. D. Mitrofanova L. I. Martynenko V. I. Spitsyn M. G. Felin 《Russian Chemical Bulletin》1988,37(7):1294-1298
| 1. | Protonated, neutral (mixed), and binuclear Cu(II), Ni(II), Co(II), Zn(II), and Mn(II) iminodisuccinate complexes have been synthesized. |
| 2. | Based on the results of IR-spectroscopic, thermal, and other methods of analysis, various conclusions have been drawn concerning the structures of these complexes; for instance, in the case of complexes of composition H2ML·nH2O both carboxyl groups are protonated, and one of them is coordinated to the metal ion. |
5.
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. |
6.
| 1. | The dissociative ionization of spin-coupled bis-chelates of Ni(II) and Pd(II) with derivatives of 1,2-hydroxylaminoxime differs very little from the behavior of coordination compounds with ligands of the nonradical type. |
| 2. | The difference in the fragmentation of Ni(II) and Pd(II) complexes is due to the greater ability of palladium to form ions containing a bond and also its smaller affinity toward oxygen. |
7.
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. |
8.
| 1. | 3,6-Di-tert-butyl-o-quinone (I) forms both hydrogen-bonded and donor-acceptor complexes with 3,6-di-tert-butylpyrocatechol (II) and 3,5-di-tert-butylpyrocatechol (III) in CCl4, and n-hexane solutions. The concentrations of these two types of complexes are approximately equal. |
| 2. | Photoreduction of quinone (I) at 77 K occurs in both the H-bonded and donor-acceptor complexes. |
| 3. | A new mechanism has been proposed to account for radical formation and stabilization in mixed complexes with both H-bonding and donor-acceptor interactions. |
9.
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. |
10.
N. F. Yudanov E. G. Boguslavskii I. I. Yakovlev S. P. Gabudar 《Russian Chemical Bulletin》1988,37(2):200-203
| 1. | A method has been developed for the intercalation of solid substances from solutions in organic solvents into graphite fluoride C2Fx. |
| 2. | Molecules of inserted paramagnetic copper complexes and nitroxyl radicals assume oriented positions between the structural layers in graphite fluoride. |
| 3. | The planes of molecules of bis-chelate Cu(II) complexes with acetylacetone, o-hydroxyquinoline, and phenylsalicylaldimine were determined to lie parallel to the C2Fx planes. |
| 4. | A method has also been suggested for the preparation of samples from C2Fx·yA compounds with a higher degree of texturizing (more nearly complete orientation) than can be achieved by pelletizing. |
11.
E. I. Matrosov N. P. Nesterova A. I. Zarubin I. A. Komolova T. Ya. Medved' M. I. Kabachnik 《Russian Chemical Bulletin》1988,37(5):935-939
| 1. | Using thermometric titration and IR spectroscopy, we investigated the reaction of carbamoylmethylphosphoryl compounds (CMP) and of some monophosphoryl compounds with HNO3 in dichloroethane and in CCl4. |
| 2. | The interaction between CMP and HNO3 takes place in two stages with sharply different H values which correspond to the formation of molecular complexes at the P=O and C=O groups. |
12.
L. F. Kozhemyakina N. I. Sheverdina I. E. Paleeva V. A. Chernoplekova K. A. Kocheshkov 《Russian Chemical Bulletin》1976,25(2):413-415
| 1. | A number of compounds of the ArSrl class were synthesized in THF solution, and the complexes of these compounds with THF were isolated. |
| 2. | Some of the reactions of these compounds were studied. |
13.
N. V. Borunova P. G. Antonov Yu. N. Kukushkin Ya. G. Mukhtarov A. N. Shan'ko L. Kh. Freidlin 《Russian Chemical Bulletin》1976,25(5):948-952
| 1. | The catalytic activity of new complexes of Pt (II)-Sn (II) with dimethylacetamide and DMF in isomerization and hydrogenation reactions of compounds containing a C=C bond is greater than the activity of the Pt-SnCl3 complex by a factor of 4–5. |
| 2. | All the examined complexes catalyzed the selective hydrogenation of phenylacetylene to styrene, and diphenylacetylene to diphenylethane passing through the stilbene stage. |
14.
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. |
15.
| 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. |
16.
| 1. | The spectra of the charge-transfer complexes of mesoionic 1,3,4-oxa, thia, and triazoles with various exocyclic groups and tetracyanoethylene have been obtained. |
| 2. | The position of the charge-transfer band provides information on the relative donor capacity of the exocyclic groups. |
17.
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. |
18.
| 1. | Rhodium complexes [RhCl(COD)]2, RhCl(PPh3)3, and RhCl3 immobilized on silica gel modified by aminophosphine groups catalyze the transfer of hydrogen from 2-propanol to cyclohexanone, styrene, and 2-cyclohexenone and the isomerization of allylbenzene in an argon atmosphere. |
| 2. | The reduction of cyclohexanone to cyclohexanol is promoted by alkali. The reaction rate is proportional to the amount of catalyst, 2-propanol concentration, and cyclohexanone. The reaction rate decreases at high ketone concentrations. |
| 3. | Styrene is reduced to ethylbenzene extremely slowly. Under these conditions, allylbenzene is not reduced, but rather undergoes isomerization with the predominant formation of trans-propenylbenzene. |
| 4. | The reduction of 2-cyclohexenone to cyclohexanol occurs by the initial reduction of the C=C bond and the subsequent reduction of the C=O group. |
19.
Z. G. Aliev L. O. Atovmyan E. A. Saratovskikh V. I. Krinichnii V. G. Kartsev 《Russian Chemical Bulletin》1988,37(11):2246-2252
| 1. | Treatment of chloropicolinic acids with aqueous solutions of various copper salts in alcohol media results in the formation of complexes of composition 21. |
| 2. | The structures of the newly synthesized complexes have been shown to be identical in the solid state and in solution. |
| 3. | Diverse modes of coordination of picolinic acid derivatives have been demonstrated; this may be one of the factors responsible for the ease of formation of metallocomplexes in biological systems, and thus may be responsible for the high biological activity (of picolinic acid derivatives). |
20.
M. A. Dzyubina G. N. Kuz'mina B. I. Kolobkov A. I. Nekhaev 《Russian Chemical Bulletin》1988,37(10):2057-2062
| 1. | The activation energy for the thermal decomposition of complexes with Fe2(CO)6S2 frameworks amounts to 103–144 kJ/mole. |
| 2. | Decarbonylation and splitting off of the hydrocarbon part of the molecule is the general pattern of behavior of iron carbonyl compounds with sulfur ligands on heating and under electron bombardment. |
| 3. | In complexes containing a norbornadiene fragment, a reverse Diels-Alder reaction takes place under electron bombardment, in addition to splitting off of norbornadiene. |