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1.
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. |
2.
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. |
3.
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. |
4.
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. |
5.
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. |
6.
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. |
7.
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. |
8.
| 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. |
9.
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. |
10.
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. |
11.
| 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. |
12.
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. |
13.
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. |
14.
A. I. Kokorin L. S. Bogach A. B. Shapiro É. G. Rozantsev 《Russian Chemical Bulletin》1976,25(9):1874-1878
| 1. | Nitroxyl biradicals of the triazine, N,N-bis(triazinyl)ethylenediamine, N,N-bis(triazinyl)piperazine, and s-nitropyrimidine series have been prepared. |
| 2. | The ESR spectra of liquid and frozen solutions of these biradicals have been obtained and N. - O group separations calculated. |
| 3. | Toluene solutions of (II), (V), (VI), and (X) biradicals contain at least four different conformations, each with its own value of the exchange integral. |
| 4. | In one of the biradical (V) conformations, spin interaction exchange is through the chain of atoms linking the N.-O fragments. |
15.
T. V. Troepol'skaya G. A. Vagina V. I. Morozov Yu. P. Kitaev 《Russian Chemical Bulletin》1988,37(6):1115-1120
| 1. | The degree of oxidation of the metal ion in the chelates of Co, Pd, and Cu with -hydroxylamine oximes is 2+ according to electrochemial and EPR data. |
| 2. | In the first stage of the electroreduction of the investigated chelates of Co with nioxime and of Cu with -hydroxylamine oxime the degree of oxidation of the metal ion in the complex changes, while in the case of the other compounds the first electrons are probably accepted by mixed molecular orbitals, to which the ligand fragment makes the largest contribution. |
| 3. | The electrode reactions of the Co(II) and Pd(II) chelates with -hydroxylamine oximes are complicated by the catalytic evolution of hydrogen from solutions containing proton donors. |
16.
N. E. Kolobova V. V. Derunov T. A. Isaeva V. N. Khandozhko 《Russian Chemical Bulletin》1988,37(2):353-356
| 1. | Propargylamines react with CpMn(CO)2(THF) to form n-amine complexes which are readily isomerized to the corresponding -aminoacetylene complexes. |
| 2. | Propargylamines react with BrRe(CO)5 in the presence of acetylacetone to give nalkenylamine complexes AcacRe(CO)3NH(R)CH2CH-CH2. |
| 3. | The first examples of cobalt -aminoacetylene complexes Co2(CO)6(4-R2NCH2CCH) have been obtained. |
17.
Z. V. Todres G. Ts. Ovsepyan E. A. Ionina A. Yu. Kosnikov S. V. Lindeman Yu. T. Struchkov 《Russian Chemical Bulletin》1988,37(8):1651-1656
| 1. | o-Dinitrobenzene dianion reacts with p-dimethylaminobenzenediazonium cation to give 2-nitro-4-dimethylaminoazobenzene. |
| 2. | o-Dinitrobenzene anion-radical reacts with benzenediazonium cations bearing a dimethylamino-or nitro-group in the para-position, to give 3-nitro-4-hydroxy-4-dimethylamino-azobenzene and 3,4-dinitro-4-hydroxyazobenzene respectively. |
| 3. | In the case of the 4-methoxybenzenediazonium cation, reaction with the o-dinitrobenzene anion-radical affords 4-methoxy-3-(2-nitrophenyl--azoxy)-4-hydroxyazobenzene, the structure of which has been established by x-ray diffraction analysis. |
| 4. | These azo-compounds are formed in solvents which favor the stability of ion pairs of the dianion or anion-radical of o-dinitrobenzene with potassium cations. Dissociation of the ion pairs results in the occurrence of electron transfer only. |
18.
I. A. Grigor'ev V. F. Starichenko I. A. Kirilyuk L. B. Volodarskii 《Russian Chemical Bulletin》1989,38(4):841-844
| 1. | In the reaction of different types of nitrones with xenon difluoride in methylene chloride, nitroxyl radicals containing one or two fluorine -atoms are formed. |
| 2. | A method is proposed for obtaining stable nitroxyl radicals containing fluorine -atoms. |
| 3. | The values of the HFI constants aF at the fluorine -atom are very sensitive to various structural factors and vary over a wide range, from 20 to 60 Oe. |
19.
R. A. Fridman G. A. Kliger E. I. Bogolepova Yu. V. Maksimov I. P. Suzdalev 《Russian Chemical Bulletin》1976,25(4):726-729
| 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. |
20.
| 1. | In urethane crystals, infinite chains of hydrogen bonds organize the urethane molecules into layers with two principal types of packing: fir-tree and stacked. The stacked packing sometimes leads to the formation of a quasiskeletal structure. |
| 2. | The geometry of the hydrogen bonds is governed by the packing of neighboring molecules. |
| 3. | The frequency of the stretching vibration band of the NH group in IR spectra cannot be used to judge the geometry of hydrogen bonds in crystalline urethanes, since the geometry is governed not only by the H...O interaction of the hydrogen bond N-H...O=C, but also by the total energy of intermolecular interaction. |