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1.
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. |
2.
| 1. | We synthesized some new iminoxyl biradicals that contain bis(azamethine), bis(azamethine)-octatriene, bis(azamethine)phenylene, bis(azamethine)thiophene, and bis(azamethine)dithienyl sulfide bridges. |
| 2. | Intramolecular spin -spin exchange in iminoxyl biradicals can be accomplished via the bis(azamethine)octatriene, bis(azamethine)-1,4-phenylene, and bis(azamethine)-2,5-thiophene systems. |
| 3. | The degree of overlapping of the orbitals of the unpaired electrons in the new biradicals was estimated. |
3.
T. Ya. Medved' N. M. Dyatlova V. P. Markhaeva M. V. Rudomino N. V. Churilina Yu. M. Polikarpov M. I. Kabachnik 《Russian Chemical Bulletin》1976,25(5):992-997
| 1. | New organophosphorus complexing agents were synthesized: ethylenediamino-N,N'-diethylphosphonic, N,N-dimethylethylenediamino-N,N-dimethylphosphonic, and N,N-dimethylethylenediamino-N, N-diethylphosphonic acids and also the iodomethylate of the last acid. |
| 2. | The acid dissociation constants for these compounds and the stability constants for their complexes with nickel, copper, dysprosium, and uranyl ions were determined. |
4.
O. A. Raevskii V. V. Tkachev V. P. Kazachenko A. N. Razdol'skii I. I. Bulgak V. E. Zubareva 《Russian Chemical Bulletin》1989,38(4):748-753
| 1. | An x-ray structure analysis has revealed substantial diferrences in the conformational states of 2,3-(4-benzoyl)benzo-15-crown-5 and benzo-15-crown-5 in the crystal phase, differences related to realization of a trans-gauche-gauche' conformation in one COCCOC fragment in the 2,3-(4-benzoyl)benzo-15-crown-5. |
| 2. | In nonpolar solvents, an equilibrium of several structures is realized in both compounds, an equilibrium with the participations of trans-gauche-trans, trans-gauche-gauche and trans-gauche-gauche' conformations. In a polar medium, there are no indications of the trans-gauch-gauche' conformation. |
| 3. | Upon complexation of the ligands with calcium thiocyanate in acetonitrile, there are spectral indications of complexes with differing stoichiometry, with a large contribution of the structure from trans-gauche-trans conformations. |
5.
Ya. I. Isakov Kh. M. Minachev G. V. Isagulyants Yu. S. Akhmetov N. N. Rozhdestvenskaya 《Russian Chemical Bulletin》1976,25(11):2267-2270
| 1. | By14C labeling, it has been shown that carbon dioxide will adsorb differently on various synthetic Ca2+-ion-containing zeolites (CaNaY, and dealuminated CaNaY and CaNdNaY) on which benzene is being alkylated by ethylene. The promoting action of CO2 is due to the presence of a weakly adsorbed form of the compound which can be readily displaced by N2 at the reaction temperature. |
| 2. | The CO2 content of the catalyst and its time variation are dependent on the zeolite composition, the re-action temperature, and the moisture content of the CO2. |
| 3. | Under fixed operating conditions, the CO2 content of zeolite 0.67CaNaY and its time variation are the same for C6H6 alkylation by ethylene and for toluene disproportionation. |
6.
Mirzayanova M. N. Medvedeva I. V. Fedulova I. E. Egorov Ts. A. Khorlin A. Ya. 《Russian Chemical Bulletin》1976,25(7):1520-1524
| 1. | The synthesis has been accomplished of the methylamides of-N-benzoyl--(N-methyl-N-phenyl-thiocarbamyl)propionic ] and butyric acids, which under the conditions used for dehydration of polypeptide chains by the Edman method through treatment with trifluoroacetic acid were converted into cyclic derivatives of hexahydropyrimidine. |
| 2. | Derivatives of D, L-erythro- and D, L-threo-diaminobutyric acid were readily and reversibly converted into one another under the action of acidic and basic reagents. |
7.
S. M. Aldoshin O. A. Kozina G. L. Gutsev E. G. Atovmyan L. O. Atovmyan V. S. Nedzvetskii 《Russian Chemical Bulletin》1988,37(10):2071-2077
| 1. | An x-ray diffraction structural study of crystals of N-(5-nitrofurfurylidene)benzhydrazide revealed the first case of the cocrystallization of syn and syn-anti isomers of ketohydrazone molecules. We propose that the isomerization of the ketohydrazone molecules occurs upon crystallization and is a consequence of packing effects. The crystal structure of this ketohydrazone is a rare case of the laminar packing of polar and nonpolar molecular chains. |
| 2. | The formation of hydrates of N-(5-nitrofurfurylidene)hydrazides radically alters the structure of their frontier molecular orbitals in comparison with the anhydrous molecules. This may significantly affect the properties of the crystals of these compounds. |
8.
| 1. | An x-ray diffraction structural analysis has established the structure of the merocyanine form of 1-hydroxyethyl-3,3-dimethyl-6-nitro-8-methoxyspiro(indoline-2,2-[2H-1]-benzopyran). The introduction of an 8-OCH3 substituent into the benzopyran fragment reduces the zwitter-ionic nature of its complex hybrid structure and increases the contribution of the less polar quinoid form, leading to increased stability of the photochromic systems derived from this type of spiropyrans relative to side-reactions. |
| 2. | The molecules in this crystal structure form strong chains due to Van der Waals interactions, which are linked by hydrogen bonds. The formation of such chains and their mutual association largely determines the structure of the absorption spectra of this compound in the solid phase and solution. |
9.
B. E. Ivanov L. A. Valitova V. I. Gaidai T. G. Bykova N. I. Kuchma S. V. Samurina 《Russian Chemical Bulletin》1976,25(11):2386-2389
| 1. | An intermediate alkoxyphosphorane with two pentacoordinated phosphorus atoms was isolated and characterized during the reaction of 2,5-bis(diethylaminomethyl)hydroquinone with trialkyl phosphites. |
| 2. | A method has been developed for the synthesis of phosphorylated dihydric phenols. |
| 3. | The triethylether of 3-ethoxy-6-hydroxy-1,4-xylyenediphosphonic acid was prepared by the interaction of 2,5-bis(diethylaminomethyl)hydroquinone with diethylphosphorous acid in the presence of triethyl phosphite. |
10.
A. M. Kritsyn L. I. Kolobushkina S. N. Mikhailov V. L. Florent'ev 《Russian Chemical Bulletin》1976,25(2):384-387
| 1. | 9-(3-Aminopropyl)adenine, racemic 9-(2-hydroxy-3-amitiopropyl)adenie and its (R)-enantiomer, and 9-(2-hydroxy-3-methylaminopropyl)adenine were synthesized. |
| 2. | A study was made of the NMR spectra of the reaction products of the -tosyloxyalkyl derivatives of uracil and thymine with ammonia and methylamine. Theories were expressed regarding the structure of the formed compounds. |
11.
V. P. Markhaeva M. V. Rudomino Yu. M. Polikarpov T. Ya. Medved' N. M. Dyatlova M. I. Kabachnik 《Russian Chemical Bulletin》1976,25(5):998-1002
| 1. | A new organophosphorus complexing agent, N,N-di-(2-hydroxyethyl)ethylenediaminodimethylphosphonic acid was synthesized, which contains additional functional hydroxyl groups in the alkyl radicals on the nitrogen atoms. |
| 2. | The acid and complex-forming properties for this complexing agent were studied. The composition was studied for the complexes using the methods of spectrophotometry, and high-frequency titration. |
12.
B. A. Arbuzov S. G. Vul'fson G. G. Butenko O. A. Samarina A. B. Teitel'baum A. N. Vereshchagin 《Russian Chemical Bulletin》1976,25(1):75-81
| 1. | The ellipsoids of polarizability of dimethylsulfone, sulfuryl chloride, and methanesulfonyl chloride were determined, and the nonadditivity of the parameters of the bonds in the sulfonyl chloride group was demonstrated. |
| 2. | Substituted methane sulfonyl chloride exist in gauche conformations. |
| 3. | In benzenesulfonyl chloride and a series of its para-substituted derivatives, the aryls are situated in the C-S-Cl plane; the para-nitro group induces a 35° rotation. |
13.
| 1. | The corresponding 1,3-bis[-(p-toluenesulfonamido)alkyl]uracils are formed as a result of the reaction of 1, 3-bis(-bromoalkyl)uracils and the Na salt of p-toluenesulfamide. |
| 2. | Interaction of l-(-bromobutyl)uracil with p-toluenesulfamide in a medium of n-butanol leads to formation of 9,18,19,20-tetraoxo-1,6,10,15-tetraazatricyclo[13.3.1.16.10]-eicosa-7, I6-diene,l-(-hydroxybutyl)-2-butoxypyrimid-4-one, and l-(-hydroxybutyl)-2-p-toluenesulfonamidopyrimid-4-one. |
14.
| 1. | The structure of the isocyanate functional group in organic isocyanates in the crystalline state is analogous to that in the gas phase. |
| 2. | The isocyanate group (H)C1-N=C2=O exists in a trans conformation in all three of the isocyanates studied. |
| 3. | The lamellar packing characteristic of ,-naphthalenediisocyanate molecules may be assigned to a structural subclass of naphthalene ¯1, namely, P(x)P21/b. |
15.
D. N. Kravtsov V. D. Vil'chevskaya P. V. Petrovskii Yu. Yu. Gorelikova 《Russian Chemical Bulletin》1988,37(5):991-994
| 1. | Ferrocene reacts with bromoadmantane in the presence of A1Cl3 to give mono- and 1,1-diadamantylferrocene. |
| 2. | Acylation of adamantylferrocene with raonoethyl o-phthaloyl chloride takes place in the 3-position of the substituted ferrocene ring, and to some extent in the free cyclopentadienyl ring. |
16.
S. G. Vul'fson A. B. Teitel'baum T. G. Mannafov A. N. Vereshchagin 《Russian Chemical Bulletin》1976,25(1):86-89
| 1. | Molecules of arylvinyl selenides have a maximally conjugated planar s-trans structure, |
| 2. | The conformations of arylvinyl sulfides are determined by the ratio of the energies of conjugation and steric repulsion of atoms; the disturbance of coplanarity occurs on account of rotation of the aryl radicals. |
17.
Kozlovskii A. G. Arinbasarov M. U. Yakovlev G. I. Zyakun A. M. Adanin V. M. 《Russian Chemical Bulletin》1976,25(5):1115-1119
| 1. | An earlier unknown metabolite ofPseudomonas aeruginosa, strain A197, 2-(n-1-heptenyl)-4-quinolone, was isolated. |
| 2. | The main components of the total mixture of alkaloids produced byPseudomonas aeruginosa strain A197 are 2-n-nonyl-4-quinolone (pseudane-IX), 2-n-heptyl-4-quinolone (pseudane-VII), 2-(n-1-nonenyl)-4-quinolone (1pseudene-IX), and 2-(n-1-heptenyl)-4-quinolone (1-pseudene-VII). |
| 3. | The synthesis of 2-(n-1 -heptenyl)- 4 -quinolones was carried out. |
18.
| 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. |
19.
| 1. | Polarizability parameters have been determined for the selenocyanate group. |
| 2. | Selenobenzene cyanate, and derivatives of this compound with donor substituants in the p position, have planar conformations; introduction of acceptor substituents breaks down the coplanarity of the C6H4-SeCN fragment. |
20.
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. |