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1.
| 1. | Following the CNDO/2 approximation to the SCF MO LCAO method, electronic parameters have been calculated for the molecules and ions of various nitro compounds. |
| 2. | Calculated values of the dipole moment and enthalpy of atomization proved to be in satisfactory agreement with the experimentally determined values, the maximum deviation between them amounting to 1.4% for the aromatic systems. |
| 3. | The nitro compound parameters most sensitive to change in the intramolecular interaction are the C-N bond energy and the charges on the carbon and halide atoms. |
2.
P. P. Levin V. A. Kuz'min R. M. Fatkulbayanov M. F. Budyka M. V. Alfimov 《Russian Chemical Bulletin》1989,38(2):225-231
| 1. | Molecules of acridine and chloroacridine in the triplet state form triplet exciplexes of the radical ion pair type with tertiary aromatic amines. Proton transfer from the radical cation to the radical anion with formation of neutral radicals is the basic pathway of quenching of these exciplexes in a nonsolvating medium. In the presence of an alcohol, the triplet exciplexes disappear due to protonation of the radical anion in the exciplex. |
| 2. | Quenching of triplet states of acridine and chloroacridine by secondary aromatic amines take place by transfer of an H atom from the amine regardless of the nature of the solvent. |
| 3. | The singlet excited state is the most probable reactive state of 9-chloroacridine in photoreduction and photosubstitution reactions with aromatic amines. |
3.
I. E. Chlenov I. M. Petrova V. M. Shitkin V. A. Tartakovskii 《Russian Chemical Bulletin》1976,25(6):1347-1350
| 1. | The reaction of 6-nitro-2,9-dioxa-1-azabicyclo[4.3.0]nonane derivatives with alcohols and alcoholates leads to remplacement of the nitro group by the corresponding alkoxy group. |
| 2. | The reaction proceeds with either a complete (for the case of the alcoholates) or predominant (for the case of alcohols) inversion of the configuration at the substitution center. |
| 3. | The reaction proceeds via the intermediately formed bicyclic immonium cation. |
4.
N. A. Malysheva A. I. Prokof'ev N. N. Bubnov S. P. Solodovnikov T. I. Prokof'eva V. B. Vol'eva V. V. Ershov M. I. Kabachnik 《Russian Chemical Bulletin》1988,37(5):907-914
| 1. | Conformational transitions characteristic of nonplanar rings were detected in the radical-cation of the 3,6-di-tert-butylpyrocatechol ester of ethylene glycol. |
| 2. | Cyclic radical-cations are formed during the oxidation of 2-acyloxyphenols. |
5.
V. A. Kuz'min P. P. Levin Yu. E. Borisevich I. A. Degterev S. M. Smirnov 《Russian Chemical Bulletin》1988,37(7):1333-1337
| 1. | The energy of the triplet electronically excited state in 5-(4-R-1-quinolyl)-2-nitrofurans and 5-nitropyromucic acid is localized chiefly on the chain of -electron conjugation of the molecules. |
| 2. | With an increase in the length of the chain of -electron conjugation in nitrofuran derivatives their reduction potential in the triplet electronically excited state decreases; this, in turn, decreases the rate constant for interaction of the triplet state with electron donors — amines. |
| 3. | As a result of interation of the triplet states of the investigated nitrofuran derivatives with tertiary aromatic amines in dioxane one observes the formation of triplet exciplexes, the principal contribution to the structure of which is made by a state with complete charge transfer, whereas their deactivation is realized via reverse charge transfer as a result of decomposition of the nitrofuran anion radical. |
6.
B. A. Arbuzov I. M. Khamatullina S. G. Vul'fson A. M. Kamalyutdinova A. N. Vereshchagin 《Russian Chemical Bulletin》1976,25(11):2296-2300
| 1. | Polarizability parameters have been obtained for the C6H5-C group in benzylidene bromides, and it has been shown that the bromine atom in these compounds interacts with the aromatic system. |
| 2. | The conformations of the nonsterically hindered benzylidene bromides are close to those in which the ring plane is shielded by the C-Br bond. |
7.
B. A. Arbuzov O. Éxsner A. P. Timosheva V. E. Kataev S. G. Vul'fson A. N. Vereshchagin 《Russian Chemical Bulletin》1976,25(6):1206-1212
| 1. | The dipole moments of the two kinds of C-O bonds in acetals and their analogs are not identical. |
| 2. | In formal molecules and the dimethylketal of acetone the C-O-C-O -C chains have gauche-gauche conformation, with the methyl groups lying on different sides of the O-C-O plane. |
| 3. | The dimethylketal of tetrachlorocyclopentadienone is represented by a mixture of trans-gauche and gauche-gauche conformers. |
8.
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. |
9.
| 1. | In inhibition of oxidation of ethylbenzene and isopropyl alcohol by secondary aromatic amines, organic acids prevent transformation of diarylaminyl radicals into nitroxyl radicals. |
| 2. | An acid increases the efficiency and duration of the inhibiting effect of secondary aromatic amines on oxidation of isopropyl alcohol, since it causes formation of quinone imine, a product of transformation of the amine which has high inhibiting activity. |
10.
Zh. A. Krasnaya T. S. Stytsenko V. I. Avdeeva D. Ya. Shagalova 《Russian Chemical Bulletin》1989,38(1):80-86
| 1. | A series of tetracyanopolymethines has been synthesized by condensation of aminals and aminal-acetals of conjugated -dimethylaminoaldehydes with malonodinitrile. |
| 2. | These tetracyanopolymethines can be used as the anionic components in cation-anion cyanine dyes. |
| 3. | The electronic absorption spectra of these newly synthesized dyes were studied in both polar and nonpolar solvents. Specific cation-anion interaction and complex formation has been shown to occur in several of these cation-anion dyes in nonpolar solvents. |
11.
Yu. V. Kuznetsov L. G. Stolyarova V. P. Lezina L. D. Smirnov 《Russian Chemical Bulletin》1989,38(7):1494-1500
| 1. | New halogen derivatives of 1-ethyl-2-methyl-, 2-methyl- and 5-hydroxybenzimidazole were obtained. |
| 2. | A method for the chlorination of aromatic compounds by an alcoholic solution of hydrogen chloride in the presence of hydrogen peroxide was proposed, which enables carrying out the reaction with a high yield. |
| 3. | The reactivity of the series of 5(6)-hydroxybenzimidazole derivatives during the electrophilic substitution (halogenation) was shown to be as follows: 1-ethyl-2-methyl-5-hydroxybenzimidazole >5(6)-hydroxybenzimidazole 2-methyl-5-hydroxybenzimidazole. |
12.
V. I. Bregadze A. Ya. Usyatinskii V. A. Antonovich N. N. Godovikov 《Russian Chemical Bulletin》1988,37(3):570-573
| 1. | Carboranyl derivatives of aluminum, gallium, and indium, containing a Ccarb-M bond, were obtained. |
| 2. | Carboranes react with trimethylgallium etherate in the presence of tetramethyl-ethylenediamine to give gallium-containing dicarbaundecaborate ions. |
13.
R. G. Kostyanovskii V. P. Leshchinskaya R. K. Alekperov G. K. Kadorkina L. L. Shustova Yu. I. Él'natanov G. L. Gromova A. É. Aliev I. I. Chervin 《Russian Chemical Bulletin》1988,37(11):2315-2323
| 1. | An efficient method of aziridine dimer synthesis is presented involving reaction of aziridine with esters of strong organic acids followed by alkaline hydrolysis of the resultant N-acyl derivatives. |
| 2. | New N-acyl and carbamoyl derivatives of aziridine dimer and trimer were synthesized. |
| 3. | Linear and branched isomers of aziridine tetramer and also diastereomers of 2-methylaziridine dimer were isolated and characterized. |
| 4. | An efficient regiospecific synthesis of 2,2-dimethylaziridine dimer and trimer was developed. |
14.
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. |
15.
| 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. |
16.
| 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. |
17.
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. |
18.
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. |
19.
B. A. Glazun R. N. Kurnosova M. M. Dubinin I. V. Zhilenkov S. S. Levchenko 《Russian Chemical Bulletin》1976,25(1):8-11
| 1. | In NaA zeolite a homocharge is formed by charges deposited on the surface of the zeolite from the gas gap between the electrode and the specimen. |
| 2. | The existence of thermoelectret effects has been found in the systems NaA-zeolite -air, NaA-helium, NaA-nitrogen, and NaA-oxygen. |
| 3. | The thermoelectret effects are caused by both the accumulation of charges in the specimen and the adsorption of molecules in the electric field. |
| 4. | A low mobility has been noted for adsorbed molecules in the electret state of the system. |
20.
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. |