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1.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 166–170, January, 1988.  相似文献   

2.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 990–994, May, 1989.  相似文献   

3.
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.
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4.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1591–1594, July, 1988.  相似文献   

5.
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.
Institute of Catalysis, Siberian Branch, Russian Academy of Sciences. Institute of Kinetics and Catalysis, Bulgarian Academy of Sciences, Sofia. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 2, pp. 29–34, March–April, 1992.  相似文献   

6.
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%.
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7.
1.  When silicas are modified with amines, not all surface silanol groups participate in the chemical reaction.
2.  When amine-modified silica gels are heated, water is produced; the maximum rate of the formation of gas occurs at 625 and 750 K. Destruction of the modifying layer begins with the liberation of ammonia at T > 640 K.
3.  Adsorption of SO2 and CO2 on aminated silicas is determined by the surface concentration of amino groups, by their nature, and by their mutual position.
Translated from Izvestiya Akademiya Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 983–990, May, 1989.  相似文献   

8.
1.  We have used the extended Hückel method to examine the interaction of singlet methylene with water and found the existence of a molecular complex CH2·H2O with an energy of stabilization of 5.6 kcal/mole and a complex CH2·2H2O with an energy of stabilization of 2.1 kcal/mole, which tends to lose one water molecule during simultaneous approach of the other.
2.  The structure of these complexes is determined by the interaction of the unoccupied methylene p orbital with the lone-pair orbitals of the water molecules.
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9.
1.  The hydrolysis rate of N-benzoylanthranilic acid was studied at a KOH concentration of 2.2–44.6% and a temperature of 25–95°.
2.  The limiting step of the process is the reaction of the singly ionized form of the reagent with a molecule of water.
3.  The equilibrium constant for the addition of hydroxyl ion to the carbonyl atom of the amido group of N-benzoylanthranilic acid is 267, and the true rate constant for the reaction of the ionized form with a molecule of H2O at 25° is 0.13 min–1.
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10.
1.  The surface of a SnO2-Sb2O4 catalyst is uniformly homogeneous with respect to the heats of adsorption of isobutylene. The heats vary from 50 to 20 kcal/mole as the degree of coverage is increased to 18% of a monolayer.
2.  Isobutylene is adsorbed on SnO2-Sb2O4 in two forms: reversible (desorbed in the range 79–100° with Edes=21 kcal/mole) and irreversible.
3.  Irreversibly chemisorbed isobutylene exists on the surface primarily in the form of the-methallyl complex.
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11.
1.  The absorption of electromagnetic radiation ( 1.05 mm) by solutions of DMSO in water and DMSO and water in dioxane has been measured in the whole interval of relative concentrations.
2.  The additivity of the absorption in systems containing dioxane, and its absence in the system H2O-DMSO, have been demonstrated.
3.  The possibility of using the absorption of radiation in the millimeter range for the study of solvation in solutions has been shown.
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12.
1.  Aluminum hydroxide and oxide supports, obtained by interaction with water of aluminum activated by indium or gallium, are multiphasic systems containing in the first case PB, BR, and In, and in the second, -Al2O3, In2O3, and In.
2.  The presence of Co and Ni as alloys with activated aluminum determined the x-ray amorphous character of the Co- and Ni-containing phases at all stages, including the thermal treatment of the hydroxide and oxide systems. In the case of the copper alloy, only with thermal treatment does the partial crystallization of the CuO phase occur.
3.  Introduction of the Co, Ni, and Cu ions into the aluminum oxide or hydroxide matrices, obtained from activated aluminum, show a definite effect on the formation of the Co3O4, CoAl2O4, and NiAl2O4 phases after thermal treatment. For the Cu-containing catalysts, the Cu2O and CuO phases are formed even before thermal treatment.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 519–523, March, 1989.  相似文献   

13.
1.  The thermal decomposition of N,N-dinitroamines is homogeneous and unimolecular in the gas phase. The limiting step of the process is the rupture of the N-NO2 bond.
2.  The activation parameters of the process imply that the dinitroamine group is more reactive than the mononitroamine group in thermal decomposition. The energy of dissociation of the N-NO2 bond in dinitroamines is 42 kJ/mole less than in mononitroamines.
3.  Nitrogen dioxide and acetaldehyde do not influence the kinetics of thermal decomposition of dinitroamines due to their high reactivity.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 790–793, April, 1989.  相似文献   

14.
1.  Selective hydrogenation of piperylene into n-amylenes (300C) on applied nickel sulfide was studied in the pulsed mode. It was found that NiS/SiO2 is more selective than NiS/Al2O3.
2.  Treatment of applied NiS with air at 300–500C oxidizes a significant portion of NiS into NiSO4, which gives the catalyst hydroisomerizing properties and permits obtaining up to 44% isoamylenes from piperylene. In contrast to oxidized NiS/SiO2, oxidized NiS/Al2O3 retains hydroisomerizing activity for a much longer time, which is due to the higher resistance of NiSO4 to reduction on Al2O3 than on SiO2.
3.  The data obtained indicate that reduced nickel atoms are the active sites of selective hydrogenation, while sulfur, sulfide or sulfate, is the surface modifier.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1477–1482, July, 1989.  相似文献   

15.
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.
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16.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1223–1228, June, 1988.  相似文献   

17.
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.
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18.
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.
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19.
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.
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20.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1468–1472, July, 1988.  相似文献   

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