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1.
A. L. Liberman T. V. Vasina S. A. Chelmakova V. N. Lutovinova 《Russian Chemical Bulletin》1976,25(1):178-180
| 1. | The yields of acyloins in acyloin condensation reactions are quite dependent on the presence of 1,3-interactions of the side chains with the H atoms of the backbone chain of the starting dicarboxylic acid esters. Contrary to the literature data, the gem effect has a comparatively small role in this reaction. |
| 2. | We synthesized 4-methylpimelonitrile, 5-methylazelaic acid and its dimethyl ester, and 4.8-dimethylcyclononanol-2-one. |
2.
A. Kh. Khusid G. V. Kryshtal' V. F. Kucherov L. A. Yanovskaya 《Russian Chemical Bulletin》1976,25(2):396-399
| 1. | A method was developed for the synthesis of acetals and aldehydes of the cyclopropane series by reducing the acetals of 1,1-dichlorocyclopropanes with sodium in liquid ammonia. |
| 2. | A method was proposed for the synthesis of 1,1-dichloro-2-methyl-3-(3-formylvinyl)cyclopropane. |
3.
| 1. | A general method of synthesis of azomethine compounds of boron has been proposed from imines and esters of thioboric acids. The reaction between ketimines and diesters of thioboroorganic acids led to the formation of diiminoboranes. Triiminoboranes were obtained on interacting ketimines and thioborates. |
| 2. | Diiminoboranes and triiminoboranes obtained from alkylarylketimines exist as mixtures of imines and enamines. |
4.
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. |
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.
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. |
7.
K. K. Babievskii I. M. Filatova V. M. Belikov L. I. Makhnova R. I. Pomilenko É. P. Sapozhnikova V. I. Sveklova 《Russian Chemical Bulletin》1976,25(12):2549-2553
| 1. | The reaction of -nitrocinnamic esters with methanol proceeds at room temperature and in the absence of base; the addition of acetic acid sharply retards the rate of the addition reaction. |
| 2. | The introduction into the -position of -nitroacryl esters of radicals containing an unshared pair of electrons on the nitrogen (3-indolyl, anilino, dimethylamino) depresses the electrophilic character of the C=C bond in these compounds, and they do not react with alcohols under analogous conditions. |
| 3. | N-Acylated -nitrovinylindole is deacylated under mild conditions under the action of alcohols. |
8.
V. F. Rudchenko I. I. Cher'vin V. N. Voznesenskii V. S. Nosova R. G. Kostyanovskii 《Russian Chemical Bulletin》1988,37(12):2513-2516
| 1. | For the first time a diastereomerically enriched acyclic NH-dialkoxyamine with asymmetric nitrogen atom in the NH group was obtained. |
| 2. | By low-temperature PMR spectra the diastereomers of a 1,1-dialkoxyurea with asymmetric amid enitrogen atom were observed. |
9.
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. |
10.
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. |
11.
| 1. | A procedure has been developed for carrying out the reaction between ozone and paraffins directly in an EPR resonator. |
| 2. | EPR signals of the products of the reaction between ozone and paraffins in the liquid phase have been obtained. |
12.
| 1. | The electrochemical chlorination of acetone in aqueous hydrochloric acid leads to a mixture of mono- and dichloro derivatives, the ratio of which is a function of the current passed. |
| 2. | The electrochemical chlorination of monochloroacetone and 1,1-dichloroacetone in carbonate buffer solution leads to 1,1,1-trichloroacetone in good yield. |
13.
V. A. Mamedov I. A. Nuretdinov Yu. Ya. Efremov F. G. Sibgatullina 《Russian Chemical Bulletin》1989,38(4):867-869
| 1. | The reaction of esters of 3-phenyl-3-chloro-2-ketopropionic acid with sodium alcoholates in alcohol (methanol or ethanol) at reflux leads to the formation of an ester of 2,5-diketo-3,4-diphenyl-3-methoxyhexanedioic or 2,5-diketo-3,4-diphenyl-3-ethoxyhexanedioic acid. |
| 2. | The reactions of esters of 3-phenyl-3-chloro-2-ketopropionic acid with the corresponding sodium alcoholates in dilute solution at 0C give the product of the substitution of chlorine by an alkoxy group in quantitative yield. |
14.
K. N. Makarov T. N. Abroskina Yu. A. Cheburkov I. L. Knunyants 《Russian Chemical Bulletin》1976,25(4):922-924
| 1. | The cesium chloride adducts with perfluoroacetone, 1-methyl-2-oxaperfluoroenanthyl fluoride, and perfluoroisobutylene react smoothly with symmetrical dichlorodimethyl ether, replacing both chlorine atoms, with the formation of the corresponding ethers. |
| 2. | The interaction of,-dihydroperfluoroamyl alcoholate with symmetrical dichlorodimethyl ether leads to the replacement of both chlorine atoms, with the formation of the corresponding ether. |
| 3. | The reaction of perfluoro-t-butylanion with tris(chloromethyl)amine leads to tris-(1,1-dihydro-perfluoroneopentyl) amine. |
| 4. | Perfluoro-t-butylanion replaces only one chlorine atom in the molecule of unsymmetrical di-chlorodimethyl ether, forming-chloro- -perfluoro-t-butyldimethyl ether. |
15.
| 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. |
16.
V. A. Smit S. O. Simonyan V. A. Tarasov A. S. Gybin G. S. Mikaélyan A. S. Shashkov S. S. Mamyan I. I. Ibragimov R. Kéipl 《Russian Chemical Bulletin》1988,37(12):2526-2535
| 1. | The intramolecular Khand-Pauson reaction is substantially accelerated when it is carried out on the surface of a Chromatographic adsorbent in the absence of a solvent. |
| 2. | A method has been developed for the preparation of substituted 3-oxabicyclo[3.3.0]-oct-5-en-7-ones, by cyclization of the dicobalt hexacarbonyl complexes of allyl propargyl ethers. |
| 3. | A novel cyclization reaction of dicobalt hexacarbonyl complexes has been found, which provides a convenient synthetic route to 4-hydroxymethylcyclopent-2-en-1-ones. |
17.
| 1. | An isokinetic relation occurs in the-elimination reaction; linearity of free energies is achieved simultaneously. |
| 2. | The isokinetic temperature, which was significantly above the reaction temperature, was determined by different methods. |
18.
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. |
19.
M. I. Kabachnik L. S. Zakharov G. N. Molchanova T. D. Drozdova P. V. Petrovskii 《Russian Chemical Bulletin》1989,38(7):1527-1532
| 1. | A method has been developed for the preparation of a series of triorganosilylmethyl esters of diphenylphosphoric acid. |
| 2. | All the triorganosilylmethyl esters of diphenylphosphoric acid which were examined undergo thermal rearrangement involving the migration of a radical from the Si atom to the methylene C atom according to a 1,2-shift. The influence of the type of radical at the Si atom on the rate of the rearrangement has been studied. |
20.
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. |