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1.
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. |
2.
V. A. Nikanorov S. V. Sergeev V. I. Rozenberg O. A. Reutov 《Russian Chemical Bulletin》1988,37(4):804-806
| 1. | The possibility was demonstrated for the base-catalyzed Knoevenagel condensation of 4-methyl-4-trichloromethyl-2,5-cyclohexadien-1-one with dimedone with the formation of 4-methyl-4-trichloromethyl-1-(4,4-dimethyl-2,6-dioxocyclohexylidene)-2,5-cyclohexadiene. |
| 2. | An explanation was offerred for the thermal stability and spectral characteristics of the semiquinoid trienedione obtained assuming polarization of the product molecule due to the presence of two extended (C=C)2C=C(C=O) cross-,,-conjugation chains. |
3.
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. |
4.
Zh. L. Dykh L. I. Lafer V. I. Yakerson A. M. Rubinshtein A. M. Taber I. V. Kalechits S. S. Zhukovskii V. É. Vasserberg 《Russian Chemical Bulletin》1976,25(2):282-286
| 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. |
5.
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. |
6.
7.
V. K. Mavrodiev I. I. Furlei E. A. Burmistrov F. Z. Galin S. N. Lakeev V. K. Ignatyuk G. A. Tolstikov 《Russian Chemical Bulletin》1989,38(3):507-511
| 1. | The stability of MNI of substituted spiro[cyclopropan-1,1-indene]-2-carboxylates is increased with increasing -system and introduction of electron acceptor substituents. The fragmentation of MNI is related to loss of substituents and is accompanied by opening of the cyclopropane ring. |
| 2. | The average lifetime of (M-R1,2) ions is measured relative to dissociation with elimination of a molecule of ethanol. |
8.
Reaction of bis (π-allyl)dipalladium dichloride with diethylcadmium and bis (triethylgermyl) cadmium
G. A. Razuvaev G. A. Domrachev V. T. Bychkov S. N. Titova I. V. Lomakova 《Russian Chemical Bulletin》1976,25(9):1984-1986
| 1. | The reaction of bis (-allyl)dipalladium dichloride with diethylcadmium, bis(triethylgermyl)cadinium, and bis (triethylgermyl)mercury was studied. The reaction proceeds with the initial formation of the 11 adduct and subsequent exchange reaction. |
| 2. | The decomposition of the intermediate [AllPdR] compounds depends on the nature of the E group. When R=Et the decomposition proceeds via the intermediate formation of the -olefin complex and the subsequent liberation of ethylene. When R=Et3Ge the decomposition includes the disproportionation reaction and the radical decomposition of the disproportionation products. |
9.
| 1. | The diene condensation of 1-alkoxy-1,3-butadienes with aliphatic aldehydes at high pressures leads to predominate formation of 2-alkoxy-6-alkyl-3-dihydropyrans, corresponding to the endo-orientation of the diene and dienophile in the transition state. |
| 2. | The observed effect is explained by the presence of interaction of the partially protonated hydrogen on the -carbon atom of the aldehyde with the -system of the diene. |
10.
T. N. Deshko A. V. Kamernitskii G. A. Kogan A. M. Turuta T. K. Ustynyuk T. M. Fadeeva 《Russian Chemical Bulletin》1976,25(12):2524-2528
| 1. | Study has been made of the circular dichroism spectra of 20-ketosteroids containing a three-membered ring (methylene, epoxide, episulfide, or aziridine) in the -position with respect to the keto group. |
| 2. | The observed n* and * transition Cotton effects have been correlated with the preferred conformation of the molecule. |
11.
Chipanina N. N. Kazakova N. A. Shestova L. A. Domnina E. S. Skvortsova G. G. Frolov Yu. L. 《Russian Chemical Bulletin》1976,25(4):915-916
| 1. | The energy of the interaction in the electronically excited state was determined from the magnitude of the shift in frequency of the vibronic maximums in the UV spectra of phenol during its formation of hydrogen bonds with 1-ethylpyrazoles, 1-ethyl-, and 1-vinylimidazole. |
| 2. | The most notable change in the energy of the hydrogen bonds during excitation is observed for 1-ethylimidazole which possesses the greatest electron-donor capability in the ground state. |
12.
| 1. | The dissociative ionization of spin-coupled bis-chelates of Ni(II) and Pd(II) with derivatives of 1,2-hydroxylaminoxime differs very little from the behavior of coordination compounds with ligands of the nonradical type. |
| 2. | The difference in the fragmentation of Ni(II) and Pd(II) complexes is due to the greater ability of palladium to form ions containing a bond and also its smaller affinity toward oxygen. |
13.
A. N. Nesmeyanov N. E. Kolobova I. B. Zlotina B. V. Lokshin I. F. Leshcheva G. K. Znobina K. N. Anisimov 《Russian Chemical Bulletin》1976,25(5):1093-1097
| 1. | The reaction of tetrakis(trifluoromethy1)allene with -C5H5Fe(CO) 2 – and Re(CO) 5 – gives -complexes. |
| 2. | On irradiation and heating, the -complex of iron is converted into the -allylidene complex. |
14.
N. K. Tatarskaya M. A. Zhurav S. M. Smirnov I. A. Degterev V. F. Tarasov Yu. E. Borisevich G. E. Zaikov 《Russian Chemical Bulletin》1989,38(4):722-726
| 1. | The decomposition of khinifur in aqueous solutions proceeds according to two parallel paths: direct photodecomposition from the first singlet activated state (monomolecular path) and reaction of the molecule in the triplet state with a molecule in the initial state (bimolecular path). |
| 2. | The first path does not depend on the pressure of oxygen in the solution, while the second path is inhibited by oxygen. |
15.
R. R. Shagidullin A. V. Chernova I. A. Nuretdinov G. M. Doroshkina E. V. Bayandina 《Russian Chemical Bulletin》1976,25(1):174-177
| 1. | Absorption bands were observed in the UV spectra of saturated selenophosphoryl compounds that were attributed to the *, n *, and n - * transitions in the selenophosphoryl group. |
| 2. | It was proposed to use the UV spectroscopy method to study the seleno-selenol isomerism in organophosphorus compounds. |
16.
| 1. | A model of geminal recombination of radical pairs generated in the triplet state in micelles including triplet-singlet transitions in radical pairs, caused by isotropic and anisotropic hyperfine interactions with strong separation of radicals and spin-orbital interaction for contact radical pairs, was proposed. |
| 2. | The spin-orbital interaction determines the rate of recombination of triplet radical pairs in micelles of small radius in strong magnetic fields. The contribution of the spinorbital interaction increases on incorporation of heavy atoms in the radicals. |
17.
N. I. Golovanova N. I. Shergina N. F. Chernov M. G. Voronkov 《Russian Chemical Bulletin》1976,25(1):166-167
| 1. | The complexing of aroxymethyltriethylsilanes with tetracyanoethylene was studied spectrophotometrically. The same relation between the ionization potentials (ID) and themax of the charge-transfer bands for p-XC6H4OCH3 and p-XC6H4OCH2Si(C2H5)3, and also for various classes of aromatic compounds, shows that the investigated molecules are donors. |
| 2. | A decrease in the ID of the studied compounds Indicates that their -donor capacity is greater than that of the corresponding anisoles. |
18.
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. |
19.
| 1. | For dyes the steric hindrance that is ereated when several hydrogen atoms are replaced by fluorine leads to a decrease of 1.5-2 times in the activation energy for the relaxation of the photoisomers and a decrease in the life span of the photoisomers by 3–4 orders of magnitude when compared with the unhindered photoisomers of the dyes. Despite the great steric hindrance, the radiationless degradation of the energy goes for the dyes by the path of cis—trans isomerization. |
| 2. | Isomerization from the triplet states of the dyes causes a rapid deactivation of the triplets in the ground state of the photoisomer. |
| 3. | Due to the high coefficient of converting the radiation and the photochemical stabilitys, 3,3'-diethyl-9-fluor othiacarbocyanine can be used successfully as an active medium for lasers. |
20.
V. A. Petrosyan A. A. Fainzil'berg M. E. Niyazymbetov V. N. Solkan 《Russian Chemical Bulletin》1989,38(5):985-989
| 1. | The MINDO/3 method has been used to calculate enthalpies in decomposition reactions of the dimethylsulfonium dinitromethylide cation radical in the gas phase; it has been shown that the most probable direction of decomposition leads to the formation of dinitrocarbene. |
| 2. | The MINDO/3 method has been used to calculate the geometric parameters and electronic structure of dinitrocarbene, and it has been shown that the singlet state is more favorable than the triplet state. It has been found that, in a series of singlet carbenes with electron-acceptor substituents, dinitrocarbene is the strongest electrophile. |