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1.
| 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. |
2.
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. |
3.
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. |
4.
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. |
5.
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. |
6.
M. M. Ermilova N. V. Orekhova E. V. Skakunova V. M. Gryaznov 《Russian Chemical Bulletin》1988,37(4):637-640
| 1. | In the course of catalytic hydrogenation reactions of cyclopentadiene, cyclooctadiene, and isoprene; and in the catalytic hydrogenolysis of propane, all of which proceed at 373–573 K, a.catalytic etching of a palladium-ruthenium membrane catalyst is taking place; it is determined by the nature of the reagents. |
| 2. | An oxidative-reductive treatment changes the surface structure, the catalytic activity, and the hydrogen permeability to a much lesser degree than when such a treatment is alternated with actual catalytic reactions. |
| 3. | A heat treatment followed by a subsequent rapid cooling from temperatures above the recrystallization temperature, increases significantly the activity of a palladium-ruthenium membrane catalyst in the hydrogenolysis of propane. |
7.
| 1. | Bimetallic powdered nickel-cobalt catalysts differing in composition and modified by RR-(+)-tartaric acid were studied in the asymmetric hydrogenation of ethyl acetoacetate. |
| 2. | The optical yield of this reaction is increased to 54% with an increase in the nickel content in the Ni-Co catalyst to 90% and is 60–65% for the nickel catalyst. |
8.
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. |
9.
| 1. | It was found that trivalent rhenium chloride has a high activity in the hydrogenation of the C=C bonds in cyclohexene, the pyridine ring, and thiophene at 200–270°, a hydrogen pressure of 130–140 atm, and a reaction time of 3 h. |
| 2. | Rhenium(III) chloride has a higher activity than rhenium heptasulfide in reducing the C=C bond in cyclohexane and the pyridine ring |
10.
Kh. M. Minachev Ya. I. Isakov V. P. Kalinin Yu. S. Akhmetov 《Russian Chemical Bulletin》1976,25(5):1041-1048
| 1. | The catalytic properties of the Ni forms of various types of synthetic zeolites in the reaction of benzene with ethylene are determined by their structure, composition, and conditions under which they are used. |
| 2. | The NiNaA zeolites accelerate only the dimerization of C2H4, and are inactive in the alkylation of C6H6 with olefins. From benzene and ethylene it is possible to obtain on NiX and NiY either predominantly sec-butylbenzene (SBB) (selectivity 80–86%) or SBB and butenes in approximately equal amounts. |
11.
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. |
12.
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. |
13.
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. |
14.
K. M. Gitis V. N. Kornyshev E. S. Shpiro A. A. Grigoryan G. V. Isagulyants Kh. M. Minachev D. P. Shashkin 《Russian Chemical Bulletin》1989,38(7):1349-1354
| 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. |
15.
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. |
16.
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. |
17.
| 1. | Ethylbenzene in acetonitrile is slowly oxidized by atmospheric oxygen to acetophenone in the presence of a catalytic amount of CrO3. |
| 2. | Ethylbenzene is oxidized to acetophenone by iodosobenzene in acetonitrile in the air in the presence of catalytic amounts of CrO3 and -picolinic acid. |
18.
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. |
19.
G. V. Chel'tsova E. I. Karpeiskaya E. I. Klabunovskii 《Russian Chemical Bulletin》1989,38(5):1014-1018
| 1. | Reductive aminolysis of 2-methyl-4-benzylidene-2-oxazolin-5-one in the chiral catalytic system PdCl2-S-phenylglycinol results in the formation of phenylalanine amides with an excess of the SS-diastereomer. |
| 2. | Reductive aminolysis in the catalytic system PdCl2-S-phenylalaninol mainly gives phenylalanine amides with an excess of the RS-diasteromer. |
20.
| 1. | Complexes of platinum with polyethyleneimine have been synthesized and characterized by spectroscopic methods. |
| 2. | It has been shown that the complex Pt(II)-PEI, reduced with sodium borohydride, is an active and selective catalyst for the hydrogenation of aromatic nitro-compounds. |