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1.
A. Teies Gonsalo A. I. Donskikh V. N. Kulagin Yu. V. Moiseev G. M. Tseitlin 《Russian Chemical Bulletin》1976,25(5):1156-1158
| 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. |
2.
B. K. Nefedov N. S. Sergeeva T. V. Zueva E. M. Shutkina Ya. T. Eidus 《Russian Chemical Bulletin》1976,25(3):565-569
| 1. | Methanol, containing 10–20 mole % of CH3I, is carbonylated to methyl acetate in the presence of impregnated Eh-zeolite NaX catalyst at 230–250° and atmospheric pressure. |
| 2. | The specific (per gram of Rh) rate of methyl acetate formation is antibatic to the Rh content in the catalyst, it increases with increase in the methanol contact time, and shows little change in the range 230–250°. |
| 3. | The rate of forming the sole secondary product, namely dimethyl ether, decreases with increase in the amount of Rh and the methanol contact time. |
| 4. | CH2I is an astoichiometric component of the reaction. |
3.
| 1. | During shaping of titanium dioxide there are formed both paramagnetic (NO 3 2– , NO2, and NO) and nonparamagnetic (NO3–) forms of nitrogen oxides, stabilized in the TiO2 lattice. |
| 2. | In CO the radicals (NO 3 2– and NO2 are reduced to NO. |
| 3. | It is postulated that during shaping of TiO2 the NO2 molecules formed during oxidation of NH3 may be stabilized both on the lattice O2– and on Ti4+. |
4.
Zh. L. Dykh L. I. Lafer V. I. Yakerson A. M. Rubinshtein A. M. Taber I. V. Kalechits S. S. Zhukovskii V. É. Vasserberg 《Russian Chemical Bulletin》1976,25(2):282-286
| 1. | At 20–220° on aluminum oxide and NaX, NaY, CeNaY, and HY zeolites, aliene isomerizes to methylacetylene; zeolites whose IR spectra are characterized by the presence of absorption bands of the hydroxyl groups (CeNaY, HY) are more active in this reaction. |
| 2. | The thermal dimerization of aliene at 450° proceeds with the formation of 1,2-dimethylenecyclobutane. |
| 3. | The oligomerization of aliene on -allylnickel bromide, applied on aluminum oxide, at 20–180° gives chiefly 1,3-dimethylenecyclobutane, the formation of which evidently proceeds through a four-membered active complex. |
5.
O. S. Morozova A. A. Kadushin V. A. Khalif E. L. Aptekar' L. Ya. Margolis O. V. Krylov 《Russian Chemical Bulletin》1976,25(4):722-725
| 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. |
6.
| 1. | A method of the measurement of the acidity function H0 of sulfo cation exchangers was proposed. It was based on their absorption of an indicator base from an aqueous solution taking into account the activity coefficient of its unionized form (fB) in the phase of the sulfo cation exchanger. This is measured in an aqueous solution of p-toluenesulfonic acid with the same molar ratio of the sulfo groups to water as in the swollen sulfo cation exchanger. |
| 2. | The fB values of o-nitroaniline in aqueous solutions of p-toluenesulfonic acid (up to 53%) were measured at 25°C. |
| 3. | The H0 values of styrene-divinylbenzene sulfo cation exchangers of the gel type KRS-1, KRS-3, KRS-6, KRS-10, and KRS-12 and the large-pore types KU-23-15/100 and KU-23-30/ 100 were measured at 25°C. |
7.
| 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. |
8.
K. K. Kalnin'sh 《Russian Chemical Bulletin》1988,37(9):1768-1773
| 1. | A new method of analysis of autocatalytic reactions was developed which permits determining the rate constants of noncatalytic and catalytic reaction pathways with the data from one kinetic curve. |
| 2. | The reverse reaction of acylation has an autocatalytic character. |
| 3. | In comparison to CHCl3, in CH3CN, all of the rate constants increase by 2–4 times, and the noncatalytic reaction pathways are more sensitive to the nature of the solvent. |
9.
A. A. Bredikhin V. A. Kirillovich A. I. Andreeva I. A. Safin A. N. Vereshchagin 《Russian Chemical Bulletin》1989,38(1):58-63
| 1. | A specific geminal interaction in the OCCl triad, which is weakened in comparison to the corresponding ethers, appears in the mono--chloro esters RCOOCClR1R2. |
| 2. | All the mono--chloro esters exist in a synclinal conformation with respect to the O-Csp3 bond with a ClCOC(O) dihedral angle equal to 70–90°. |
10.
M. G. Chauser O. S. Anisimova L. S. Kol'tsova N. L. Zaichenko M. I. Cherkashin 《Russian Chemical Bulletin》1988,37(1):58-60
| 1. | A comparison of the results of studying the products of thermal polymerization of phenylacetylene by mass spectrometry and13C NMR showed that tetra-substituted cyclohexadiene and/or benzene rings are the terminal groups in polyphenylacetylene macromolecules. |
| 2. | The terminal cyclohexadiene rings are formed as a result of chain breaking by intramolecular cyclization of the propagating end. |
11.
S. P. Freidman N. I. Medvedeva G. S. Nazarova V. A. Gubanov 《Journal of Structural Chemistry》1991,32(5):631-636
| 1. | The Al–O and P–O chemical bonds in variscite are mainly covalent in nature. The degree of covalency of the P–Ob chemical bond is substantially greater than that of Al–Ob. |
| 2. | The presence of nonequivalent bonds of oxygen atoms in water molecules in variscite (H–OW–H) and bonds of bridge oxygen atoms (P–Ob–Al) leads to splitting of the 02s and 02p states of the OW and Ob atoms amounting to 7 eV. |
| 3. | The strength of the Al–OW bond is considerably lower than that of the Al–Ob bond. |
| 4. | The H11, H21, and H22 hydrogen atoms form hydrogen bonds with the bridge oxygen atoms, but H12 does not participate in hydrogen bonding. |
| 5. | The results from cluster calculations of the electronic structure of variscite provide a basis for interpreting the experimental x-ray photoelectron spectrum and for determining the influence of structural molecules of water on the XPS line shape and structure. |
12.
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. |
13.
O. V. Bragin V. L. Yakerson T. V. Vasina S. A. Isaev L. I. Lafer V. D. Nissenbaum 《Russian Chemical Bulletin》1989,38(2):212-216
| 1. | The H-pentasil--Al2O3 catalytic system exhibits high activity and selectivity in the 350–500°C temperature range in the reaction of aromatization of ethylene, A sharp increase in the activity is observed when HTsVM (0.5–10%) is incorporated in Al2O3, and a moderate increase is observed on incorporation of Al2O3 in HTsVM. |
| 2. | A correlation between the activity and number of strong Brønsted and Lewis sites, determined spectrally by adsorption of pyridine, was found for the HTsVM-Al2O3 catalytic system; it was concluded that Brønsted and Lewis sites are required for the reaction of aromatization of ethylene. |
| 3. | The absence of additivity in the hydrophilic properties in comparison to the properties of the pure components was found in the HTsVM-Al2O3 system; it was hypothesized that this effect reflects a change in the organophilic properties, which has a positive effect on the activity and selectivity of the process. |
14.
R. G. Bulgakov V. N. Yakovlev G. Ya. Maistrenko G. A. Tolstikov V. P. Kazakov 《Russian Chemical Bulletin》1988,37(12):2458-2462
| 1. | The effect of oxygen on the chemiluminescent reaction of alkyl organoaluminum compounds with xenon difluoride was determined. The emission becomes stronger or weaker depending on the concentration of oxygen in the solution. |
| 2. | In addition to the main source of emission (reactions not containing O2 radicals), there is an additional source due to the transformation of the alkyl radicals (reaction intermediates) into peroxyl radicals, which disproportionate with the emission of light. |
15.
| 1. | Chemiluminescence on hydrolytic reduction of perxenate ions is accompanied by at least three subsequent reactions: decay of XeO6 4– ion and reduction of H2O2 by XeO6 4– ions and XeO3. |
| 2. | UO 2 2+ ions act not only as energy acceptors, but also as inhibitors of the reduction reaction of XeO6 4–. |
16.
S. M. Kulikov M. N. Timofeeva I. V. Kozhevnikov V. I. Zaikovskii L. M. Plyasova I. A. Ovsyanikova 《Russian Chemical Bulletin》1989,38(4):687-691
| 1. | Silicotungstic heteropolyacid is sorbed by silica gels, activated charcoal, and -Al2O3 from water and from organic oxygen-containing solvents, forming three formations distinguishable by electron microscopy. |
| 2. | The relative proportions of the surface forms are determined by the type of substrate, solvent, and the HPA concentrations on the substrate. The most uniform covering is achieved when HPA is adsorbed from ethyl acetate. |
17.
T. E. Kron V. S. Lopatina L. N. Morozova S. A. Lebedev L. S. Isaeva D. N. Kravtsov é. S. Petrov 《Russian Chemical Bulletin》1989,38(4):703-707
| 1. | The complexes ArNiXL2 and HNiXL2 (X is halide, L is tertiary phosphine) in the presence of zinc catalyze the condensation of bromobenzene with styrene (stilbene formation). |
| 2. | The yield of stilbene and 1,3-diphenylbutene, the dimerization product of styrene, in the presence of pyridine is lowered according to the substitution of phenyl groups on the phosphorus ligand L by alkyl (ethyl, cyclohexyl) groups. |
| 3. | Change of triphenylphosphine to phenylethylphosphines and tricyclohexylphosphine in the hydride complex HNi(X)(PR3)2, the catalytic activity of which falls in the order X=Cl–Br–>I–, favors the dimerization of styrene in the absence of pyridine. |
18.
| 1. | The existence of synergism is demonstrated; the activity of Pd-Tc/carrier catalysts in the dehydrogenation of hydrocarbons considerably exceeds that of monometallic catalysts. The most active catalysts are those with PdTc ratios from 11 to 23. |
| 2. | In terms of reactivity on Pd-Tc catalysts, the hydrocarbons are arranged as follows: cyclohexene > cyclohexane > methylcyclohexane > ethylcyclohexane > n-hexane. |
| 3. | Activity in the dehydrogenation of cyclohexane varies as follows: Pd-Tc/-Al2O3 > Pd-Tc/MgO > Pd-Tc/TiO2 > Pd-Tc/Y2O3 > Pd-Tc/SiO2. |
| 4. | A decrease in CO chemisorptive capacity on bimetallic catalysts compared to monometallic catalysts is established. |
19.
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. |
20.
| 1. | Syntheses were reported for 1,2-disubstituted silylcyclopropanes by the reductive cyclization of RCCl2CH2CHClSiMe3 compounds. |
| 2. | The cyclization upon the reduction of ClCH2CH2CCl2CH2CHClSiMe3 using metallic zinc proceeds with involvement of both the CH2C1 and CHC1 groups. The product ratio depends significantly on the solvent. |