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1.
| 1. | The rate of hydrogenolysis of propane and the selectivity for methane in delivery of hydrogen through a Pd-Ru alloy membrane catalyst is lower than in conducting the reaction in conditions of combined delivery of hydrogen and propane. |
| 2. | In the 433–533 K temperature region corresponding to the coexistence of the and phases of palladium hydride, the rate of hydrogenolysis of propane does not increase with an increase in the temperature. |
2.
G. Grossman G. Komber G. Kroshvitts P. A. Kirpichnikov N. A. Mukmeneva D. G. Pobedimskii 《Russian Chemical Bulletin》1989,38(1):26-32
| 1. | Dithiophosphoric acids are either not catalysts or only act as moderate catalysts as a function of the structure in reactions of decomposition of CHP. |
| 2. | The real catalyst of decomposition of CHP in the presence of dithiophosphoric acids is the sulfuric acid formed during the oxidation of the dithiophosphoric acids, or the combination of the sulfuric acid with phosphours-containing acids. |
| 3. | Slow and fast stages of kinetic decomposition of CHP were detected, and the kinetic parameters of the fast stage were determined. |
3.
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. |
4.
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. |
5.
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. |
6.
| 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. |
7.
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. |
8.
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. |
9.
A. M. Moiseenkov V. A. Dragan A. V. Lozanova V. V. Veselovskii 《Russian Chemical Bulletin》1988,37(8):1603-1609
| 1. | Dimethyl, diphenyl, and tetramethylene sulfoxide hydrochlorides react with methylheptenyl, citronellyl, and geranyl acetates to give predominantly the allylic chlorination products. |
| 2. | These findings are preferably to be regarded as involving AdE reactions between the weakly electrophlic hydroxy and (or) chlorosulfonium cation and the trisubstituted C=C bond in these olefins at the key stage. |
| 3. | The addition of lithium perchlorate has been found to accelerate this reaction. |
| 4. | Sulfoxide hydrobromides are highly selective brominating agents for the terminal grouping in isopropenoid oligoolefins. |
10.
Presently, a large variety of layered materials are synthesized that are able to intercalate neutral guest molecules or to exchange inorganic and organic ions for interlayer ions. Several of these materials are also found as minerals.The intracrystalline reactivity of a few selected compounds will be described and compared to clay minerals:
相似文献
| – | - intercalation into crystalline silicic acids; |
| – | - reactions of phosphates, arsenates, and sulfates; |
| – | - reactions of titanates, niobates, and molybdates with long chain alkylammonium ions, and |
| – | - anion exchange properties of double hydroxides. |
11.
D. D. Gogoladze E. S. Levitina L. F. Godunova E. I. Karpeiskaya E. I. Klabunovskii G. O. Chivadze 《Russian Chemical Bulletin》1988,37(6):1207-1210
| 1. | Hydrogenation of -nitrpcaprolactam by treatment with a Pd catalyst in the presence of S--phenylethylamine in aprotic solvents proceeds via azoxycaprolactam as an intermediate. |
| 2. | The asymmetric effect in the enantioselecive hydrogenation of nitrocaprolactam on a chiral Pd catalyst occurs at the stage where azoxycaprolactam is reduced. |
12.
G. A. Artamkina A. Yu. Mil'chenko I. P. Beletskaya O. A. Reutov 《Russian Chemical Bulletin》1988,37(12):2550-2556
| 1. | The kinetics of reactions of alkali metal salts of 9-carbomethoxy- and 9-cyanofluorene with para-nitrofluorobenzene and of Me3SnM with pentafluoropyridine have been studied. |
| 2. | In the case of carbanions the free anions are more reactive, while in the case of Me3SnM the corresponding tight (contact) ion pairs are more reactive. |
| 3. | The effect of the leaving group (on reactivity) was investigated using the reactions of pentafluorochlorobenzene with the K salts of 9-carbomethoxyfluorene and cyclopentadienylirondicarbonyl anions as examples. |
| 4. | The reaction mechanism has been shown to depend on the nature of the nucleophile. |
13.
B. A. Kazanskii M. I. Rozengart V. L. Polinin V. G. Bryukhanov L. V. Kravtsova N. I. Kolpakova 《Russian Chemical Bulletin》1976,25(8):1685-1690
| 1. | Cyclohexadiene, bensene, and methylcyclopentadienes are mainly formed from the hexatriene in the presence of silica gel and Al2O3 at 300–450°C. Increase in temperature (from 550 to 1100°C) and in the length of calcination of the silica gel (1–6 h) reduces the specific surface area and acidity of the catalyst and the degree of 1–5 and 1–6 cyclization of the triene. |
| 2. | In the presence of ZnO and Bi2O3, 1–6 cyclization of hexatriene to cyclohexadiene and benzene mostly occurs; methylcyclopentadienes are formed in insignificant amounts. |
| 3. | The 1–5 cyclization of hexatriene on silica gel and Al2O3 evidently takes place by a mechanism of acidic intramolecular alkylation. At 300–450°C, catalytic 1–6 cyclization of hexatriene is observed in addition to the thermal reaction. The idea was put forward that the catalytic 1–6 cyclization is facilitated by acceleration of the isomerization of the trans-triene to the cis isomer and by the effect of the catalyst surface on the conformation of the cis-hexatriene molecules. |
14.
| 1. | N-Ethyl and N-isopropyl-3-piperidones were synthesized and the stereochemistry of their reduction was studied. |
| 2. | The dependenceof stereochemistryof a series of reactions at the carbonyl center on bulk of the substituent on nitrogen was established. |
| 3. | Pure a- and e-epimers of N-ethyl- and N-isopropyl-3-piperidols were separated. |
15.
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. |
16.
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. |
17.
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. |
18.
L. F. Chertanova G. A. Marchenko A. A. Gazikasheva Yu. T. Struchkov V. F. Sopin L. N. Punegova A. S. Mukhametzyanov 《Russian Chemical Bulletin》1989,38(2):250-253
| 1. | The planar alkoxydiazinoxide fragments are shown to have the Z-configuration and be orthogonal to each other by an x-ray structure study of a series of alkoxydiazinoxides. |
| 2. | In the oxydiazinoxide fragments, p- conjugation occurs. |
| 3. | The molecules of the compounds in the crystals studied are joined by hydrogen bonds. |
19.
I. N. Lisichkina A. I. Vinogradova M. B. Saporovskaya V. K. Latov V. M. Velikov 《Russian Chemical Bulletin》1988,37(5):1029-1031
| 1. | The catalytic system obtained upon the reaction of S- and R-MetHPdCl2 with H2 or NaBH4 has high catalytic activity in the hydrogenation of cinnamic acid derivatives, but the enantioselectivity of this reaction does not exceed 3–3.4%. |
| 2. | The hydrogenation of N-Ac-APhe-S-Tyr in the presence of both R- and S-MetHPdCl2 leads to a product with an 18–24% diastereomeric excess of the R, S isomers. |
20.
M. M. Dubinin O. Kadlets L. I. Kataeva B. A. Onusaitis 《Russian Chemical Bulletin》1988,37(5):849-854
| 1. | The adsorption properties with respect to benzene vapors and the pore structure of carbon adsorbents with almost maximum development of the microporosity were studied. |
| 2. | The position of the micropore volume distribution curves whose maxima correspond to a size (halfwidth) of 1.2–1.4 nm and micropore volumes 1.5 cm3/g is a characteristic feature of the adsorbents studied. The difference between ordinary active carbons and the active carbons investigated is only quantitative in the values of the parameters of the Dubinin-Stockley adsorption equation. |
| 3. | The adsorption isotherms are described by the adsorption equation from the theory of volume filling of micropores in a wide range of equilibrium relative pressures and temperatures of 293–353 K with totally satisfactory precision. |
| 4. | The question of the upper limit of the micropores of carbon adsorbents is discussed. |