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1.
S. F. Vasilevskii A. N. Sinyakov M. S. Shvartsberg I. L. Kotlyarevskii 《Russian Chemical Bulletin》1976,25(10):2134-2138
| 1. | Depending on the conditions, the reaction of methyl aryl ketones with phosphorus pentachloride leads to products from substitution of the carbonyl oxygen by chlorine, αβ-dichlorovinylarenes, or compounds with higher degrees of chlorination. |
| 2. | By eliminating a molecule of hydrogen chloride under the influence of an equimolar amount of sodium amide in ammonia, substituted, α,β-dichloroethylenes give high yields of the respective 2-chloroacetylene. |
| 3. | The synthesis of a series of ethynyl- and β-chloroethynylpyrazoles from methylpyrazolyl ketones was realized. |
2.
A. S. Vorob'ev I. I. Furlei A. Sh. Sultanov V. I. Khvostenko G. V. Leplyanin A. R. Derzhinskii G. A. Tolstikov 《Russian Chemical Bulletin》1989,38(7):1388-1394
| 1. | The formation of resonance states of negative molecular ions by interaction of an electron with the molecules of ethylene oxide, ethylene sulfide, and their derivatives in the high-energy region takes place through a mechanism of electronically excited Feschbach resonance with excitation of an electron from several occupied molecular orbitals to one and the same unoccupied molecular orbital, which coincides with the unoccupied molecular orbital of the first singlet transition of the molecule. An additional electron is captured in a fully symmetric Rydberg orbital that is formed in the field of the excited molecule. |
| 2. | The dissociation of the negative molecular ions proceeds in accordance with the principle of orbital correlation, and the symmetry of their electronic state is determined by the symmetry of the occupied molecular orbital (from which the electron is excited) and the symmetry of the unoccupied molecular orbital (into which the electron passes). |
| 3. | In the molecules of 2,3-epoxypropyl ethyl sulfide, glycidol, and epichlorohydrin, the unshared electron pairs of the oxygen atom of the three-membered heterocycle and the sulfur atom of the substituent (or the oxygen or chlorine atom of the substituent) do not interact with each other to any appreciable degree. |
3.
| 1. | The kinetics of the Cannizzaro reaction of benzaldehyde in aqueous KOH solution have been studied spectrophotometrically, working at 25°C and at concentrations ranging from 19.1 to 37.9%. |
| 2. | Reaction proceeds through the formation of an activated complex consisting of the doubly ionized and the un-ionized forms of benzaldehyde and the hydroxide cation. |
| 3. | The spectrophotometric data and the kinetic data have been combined to give an estimate of the benzaldehyde ionization constant in aqueous KOH solution at 25°C. |
| 4. | Analysis of the kinetic data for benzaldehyde reduction by formaldehyde has shown the activated complex for this reaction to be composed of an un-ionized benzaldehyde molecule and a doubly ionized formaldehyde molecule, with or without participation of the hydroxide cation. |
4.
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. |
5.
V. G. Genchel' N. V. Demidova N. S. Nametkin L. E. Gusel'nikov E. A. Volnina E. N. Burdasov V. M. Vdovin 《Russian Chemical Bulletin》1976,25(10):2181-2184
| 1. | Employing the method of the joint combustion of organosilicon compounds with benzotrifluoride in oxygen, the formation enthalpies of 1,1-dimethyl-1-silacyclobutane, 1,1,3,3-tetramethyl-1,3-disilacyclobutane, and 1,1,3,3,5,5-hexamethyl-1,3,5-trisiliacyclohexane were determined for the first time. |
| 2. | An estimate was made of the strain energy of 1,1-dimethyl-1-silacyclobutane and 1,1,3,3-tetramethyl-1,3-disilacyclobutane. |
6.
| 1. | The principal reaction path for flash photolysis of fluorotrinitromethane (FTNM) in alcoholic solvents is that leading to the formation of fluorodinitromethane anions through an ionic mechanism. |
| 2. | Study has been made of the kinetics of FDNM anion formation in FTNM photolysis in abs. methanol containing CH3ONa. It was found that the reaction is first order with respect to the FTNM. |
7.
G. S. Kalinina E. A. Shchupak N. S. Vyazankin G. A. Razuvaev 《Russian Chemical Bulletin》1976,25(6):1289-1292
| 1. | Tris[tris(trimethylsilylmethyl)stannyl]- and tris[tris(trimethylsilylmethyl)germyl] thallium, the first stable compounds containing Sn-Tl and Ge-Tl bonds, have been prepared by the reaction of the hydrides of tris (trimethylsilylmethyl)tin and tris (trimethylsilylmethyl)germanium with triethylthallium. |
| 2. | The Sn-Tl bond is attacked in the reactions of the stannylthallium compound with lithium, mercury, oxygen, bromine, ethyl bromide, ethanol, and other reagents. |
8.
A. K. Mal'tsev N. D. Kagramanov I. O. Bragilevskii N. G. Komalenkova S. A. Bashkirova D. A. Zagorets M. Ya. Kel'man E. A. Chernyshev O. M. Nefedov 《Russian Chemical Bulletin》1989,38(5):950-956
| 1. | Differences have been shown in the mass spectra of isomeric 1,1-difluoro- and 1,1-dichloro-1-silacyclopentenes, and also 1,1-dichloro-, 1,1-dihydro-, and 1,1-dideuterio-1-silacyclohexadienes, differences that make it possible to identify the isomers. |
| 2. | Mass spectrometry has been used to identify the intermediates formed in the vacuum pyrolysis of these silicon-containing cyclic compounds, and it has been established that all of the dihalo derivatives dissociate selectively, splitting off the corresponding dihalosilylene. |
| 3. | In the thermal dissociation of sila-2,5-cyclohexadiene, hydrogen splits off selectively from the silicon atom and one of the carbon atoms, forming silabenzene — a molecule with a multiple carbon-silicon bond. The mass spectrum of silabenzene has been obtained for the first time. |
9.
| 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. |
10.
A. Teies Gonsalo A. I. Donskikh V. N. Kulagin Yu. V. Moiseev G. M. Tseitlin 《Russian Chemical Bulletin》1976,25(5):1156-1158
| 1. | The hydrolysis rate of N-benzoylanthranilic acid was studied at a KOH concentration of 2.2–44.6% and a temperature of 25–95°. |
| 2. | The limiting step of the process is the reaction of the singly ionized form of the reagent with a molecule of water. |
| 3. | The equilibrium constant for the addition of hydroxyl ion to the carbonyl atom of the amido group of N-benzoylanthranilic acid is 267, and the true rate constant for the reaction of the ionized form with a molecule of H2O at 25° is 0.13 min–1. |
11.
| 1. | The molecular-sieve properties of a number of synthetic and natural chabazites have been investigated. |
| 2. | Characteristic differences have been revealed in the molecular-sieve properties, thermal stability, and x-ray characteristics between the two groups of the zeolites studied. |
| 3. | A reversal of the molecular-sieve effect on passing from the calcium to the sodium-calcium forms of certain synthetic and natural chabazites has been observed. |
12.
V. M. Gryaznov V. S. Smirnov S. G. Gul'yanova M. M. Ermilova 《Russian Chemical Bulletin》1976,25(3):490-493
| 1. | Oxygen diffusing through a silver membrane catalyst is more active in the formation of products of the complete oxidation of ethylene than oxygen introduced in a mixture with ethylene. |
| 2. | The permeability of silver to oxygen passes through a minimum with increasing ethylene pressure at the output surface of the silver membrane and reaches a value equal to the permeability in the case of diffusion into vacuum. |
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.
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. |
15.
Lagerge S. Kamyshny A. Magdassi S. Partyka S. 《Journal of Thermal Analysis and Calorimetry》2003,71(1):291-310
A new batch titration microcalorimeter has been used for estimation of thermodynamic properties in various investigated colloidal systems. As examples, we present enthalpic and kinetic data obtained from this calorimetric device for four different processes widely encountered in colloid science:
This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
| (i) | The dilution/micellization process of cationic gemini surfactants in aqueous solution. |
| (ii) | The hydration process of non ionic surfactants in organic solution, i.e. the mechanism of micellar solubilization of water in the aggregates. |
| (iii) | The complexation of calcium ions by polyacrylates sodium salts (PaNa). |
| (iv) | The adsorption phenomenon of PaNa molecules on the calcium carbonate surface. |
16.
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. |
17.
| 1. | Using DMSO and MeSOPh it has been shown for the first time that O-trifluoroacetylated sulfoxides react with unactivated trisubstituted olefins to give allylsulfonium salts. |
| 2. | LiClO4 has been found to accelerate this ene-type reaction. |
| 3. | It has been found for the first time in the aliphatic series that the competition between [3, 2]-rearrangement and the Stevens rearrangement of the S-ylid generated from the allylsulfonium salt is governed by the type of counterion present, and this observation has been rationalized. |
18.
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. |
19.
M. A. Dzyubina G. N. Kuz'mina B. I. Kolobkov A. I. Nekhaev 《Russian Chemical Bulletin》1988,37(10):2057-2062
| 1. | The activation energy for the thermal decomposition of complexes with Fe2(CO)6S2 frameworks amounts to 103–144 kJ/mole. |
| 2. | Decarbonylation and splitting off of the hydrocarbon part of the molecule is the general pattern of behavior of iron carbonyl compounds with sulfur ligands on heating and under electron bombardment. |
| 3. | In complexes containing a norbornadiene fragment, a reverse Diels-Alder reaction takes place under electron bombardment, in addition to splitting off of norbornadiene. |
20.
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. |