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1.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 773–776, April, 1989.  相似文献   

2.
1.  A new group of ethylenediaminodialkylphosphonic acid esters and higher alcohols has been synthesized.
2.  Study has been made of the extraction of Au(III) from hydrochloric acid solution by the esters of these acids. It has been shown that the extract is a 11 metal-to-ligand complex. The distribution coefficient of the Au(III) extraction increases with the dielectric constant of the extracting solvent. It has also been established that the Au(III) can be reextracted out of the organic phase by NH3 or HNO3.
3.  Study has been made of the extraction of Nd(III), Ce(III) and Ce(IV) ions by the octyl ester of ethylene-diaminodiisopropylphosphonic acid. Extraction of these ions can be carried out almost quantitatively at pH values in the 7.5–8.5 interval.
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3.
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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4.
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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5.
1.  Study has been made of the IR spectra of N--polynitroalkylhydrazine derivatives, band assignments being made for stretching vibrations in the NH, C=O, and NO2 groups.
2.  Integral intensities for NO2 antisymmetrical stretching absorption bands are additive. Splitting of these bands is characteristic of nitro compounds containing a hydrazine radical in the -position with respect to the nitro group.
3.  It has been shown that intermolecular hydrogen bonding exists in the N--polynitro-alkylhydrazines, in the crystalline state and in concentrated solution.
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6.
1.  The complexes AcBr·AlBr3 and AcBr·2AlBr3 initiate cationic polymerization of isobutylene in hydrocarbon medium at –78°C and the complex AcBr·2AlBr3 is more active.
2.  Initiation of polymerization under the effect of the AcBr·2AlBr3 complex in hexane at –78°C takes place exclusively with Ac+ and the initiating capacity of the AcBr·AlBr3 complex is due to generation of a proton in the reaction of this complex with the monomer.
3.  Under the effect of AcBr·AlBr3 and AcBr·2AlBr3 complexes, chain breaking takes place with the formation of the same C-Br and C=C terminal groups with similar ratios equal to 21.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2232–2238, October, 1988.  相似文献   

7.
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.
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8.
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.
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9.
1.  It was shown by the UV spectroscopy method that the active initiators of the Liquid-phase carbonylation of amines with CO are oxidizing agents that form charge-transfer complexes with the amines.
2.  The carbonylation of piperidine with CO in the presence of I2 or KMnO4 is inhibited by excess initiator The addition of a second initiator to the reaction system retards the carbonylation due to a decrease in the rate of forming the complex of the first initiator with the amine.
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10.
1.  The effect of dilution with inert solvents on the dissociation of BuLi complexes with the electron donors, OMe2, OEt2, NEt3, and SEt2 has been studied through PMR spectra. Data concerning the stability of donor — acceptor complexes has been obtained.
2.  Interaction of BuLi with dimethyl ether leads to the formation of a 11 complex. Fewer than four molecules of the donor add to the tetramer in other cases.
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11.
1.  The compounds of the platinum group metals (Pt, Pd, Rh, Ir) are active in cleaving the Si-Ph and the Si-alkyl bonds.
2.  Some of the compounds of platinum metals (H2PtCl6·6H2O, PtCl4, RhCl3 · 3H2O, Na2IrCl6) have a catalytic effect on the cleavage of Si-C bond.
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12.
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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13.
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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14.
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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15.
1.  The potential energy of the interaction of one water molecule with the walls of a micropore E(Zc) as a function of the distance to its lower surface has one or two minima, determined by the half-width of the micropore d.
2.  The height of the barrier U between the minima of E(Zc) and distance R between these minima for a given model potential of the water-carbon interaction increase linearly with an increase in the slit half-width. The values of the coefficients of these linear dependences were obtained empirically.
3.  The dependence of the transverse diffusion coefficient on d for one molecule of water has one distinct maximum at d 0.41 nm. For this micropore, the height of the barrier gDU between the minima of E(Zc) is kT. For a cluster of six water molecules, there is also a maximum, but at d 0.35 nm, which is due to the formation of hydrogen bonds between the molecules of water.
4.  Note that with a micropore half-width of d > 0.375 nm, for a cluster of 19 molecules of water, the number of hydrogen bonds is 18 per cluster and increases monotonically with an increase in d from 0.36 to 0.46 nm. In the 0.47–0.5 nm region, the average number of hydrogen bonds is almost independent of d.
5.  When d < 0.42="" nm,="" the="" hydrogen="" bonds="" prevents="" the="" optimum="" orientation="" of="" the="" molecules="" with="" respect="" to="" the="" nearest="" surface="" of="" the="" pore="" and="" when="" d=""> 0.425 nm, they favor localization of the water near the walls of the micropore.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1703–1709, August, 1988.  相似文献   

16.
1.  As the number of fused rings in the ligand of the cuprous organoacetylenides with the general formula ArCCCu, where Ar may be phenyl, -naphthyl, -naphthyl, or 9-anthracenyl, is increased, there is a tendency toward a bathochromic shift in the absorption, photoconductivity, and photoelectromotive-force spectra. Para substituents in the phenyl ring cause increasing bathochromic shifts in the absorption maxima along the series CH3 < h=">< cl=">< i="><>3 <>2.
2.  The photoeleetromotive-force spectra are similar to the absorption spectra, and the principal photoconductivity maximum is located on the edge of the absorption band.
3.  The photoconductivities determined from the absorption spectra and the energies of the forbidden gaps determined from the photoelectromotive-force spectra correlate well with each other. This indicates that the conductivity of the cuprous organoacetylenides is intrinsic. The p type of the photocurrent carrier has been established.
4.  The nature of the spectra of the cuprous organoacetylenides as a function of the method of construction has been discussed, and the decisive role of the steric factors in the migration of the photocurrent carriers has been shown.
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17.
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   

18.
1.  Three complexes of sodium bis[N-3-substituted-salicylidene-S-valinato]cobaltate(III) were synthesized where the salicylaldehyde residue was substituted in position 3 with the NO2, i-C3H7, and t-C4H9 groups. The (SS)- and (SS)-diastereomers of the complexes were separated and their structure and configuration were demonstrated by elemental analysis and physical methods.
2.  The stereoselective effects in these compounds were studied and it was shown that by varying the bulk and electronic effects of groups in the salicylaldehyde ring (from 5-NO2 to 3-t-C4H9) the relative energy of diastereomers can be changed in the interval of 2.6 kcal/mole.
3.  Stereoselective effects were studied in the complexes potassium - and -bis[N-salicyliden-S-alaninato ]cobaltate(III) and potassium - and -bis[N-salicylidene-S-valinato]cobaltate(III) in various solvents and it was shown that the solvent has at least no less an effect on the energy difference of diastereomers than do the substituants introduced into the complex molecule.
4.  The energy difference of diastereomers in a series of alcohols correlates with the dielectric constant of the solvent, which indicates the important role of electrostatic interactions in complexes.
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19.
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.
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20.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 272–276, February, 1988.  相似文献   

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