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1.
1.  Telomerization of 1-hexene with butyraldehyde results in the formation of two main series of telomers — ketones and hydrocarbons.
2.  In the reaction studied, radical rearrangement with 1,6-migration of a hydrogen atom along the chain containing a carbonyl group occurs to a significant extent.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 874–878, April, 1989.  相似文献   

2.
1.  A new group of ethylenediaminodialkylphosphonic acid esters and higher alcohols has been synthesized.
2.  Study has been made of the extraction of Au(III) from hydrochloric acid solution by the esters of these acids. It has been shown that the extract is a 11 metal-to-ligand complex. The distribution coefficient of the Au(III) extraction increases with the dielectric constant of the extracting solvent. It has also been established that the Au(III) can be reextracted out of the organic phase by NH3 or HNO3.
3.  Study has been made of the extraction of Nd(III), Ce(III) and Ce(IV) ions by the octyl ester of ethylene-diaminodiisopropylphosphonic acid. Extraction of these ions can be carried out almost quantitatively at pH values in the 7.5–8.5 interval.
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3.
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.
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4.
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.
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5.
1.  2-Methoxy-, 2-methoxy-4-methyl-, 2-methoxy-5,5-dimethyl-, 2-chloro-, 2-chloro-4-methyl-, and 2-chloro-5,5-dimethyl-1,3,2-dioxastibinanes have been prepared.
2.  The bands due to the group vibrations (Sb-O) and (Sb-Cl) have been identified in the infrared and Raman spectra of the acyclic and cyclic esters and chlorides of antimonous acid obtained.
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6.
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.
Translated from Izvestiya Akadamii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 962–964, April, 1989.  相似文献   

7.
1.  The acid properties of short-lived radicals from the pyrrole, indole, benzazole, and benzoquinone series were studied by nanosecond laser spectroscopy in acetonitrile.
2.  The linear dependence of the change in the standard free energy of formation of neutral radicals as a result of transfer of an H atom from the heterocyclic molecules to the quinone molecules and a change in the standard free energy of electron transfer in these systems was demonstrated.
3.  The role of intermediate states with electron transfer in the process of photoinduced cleavage of the hydrogen atom was investigated. It was found that the efficiency of formation of products of atom transfer is determined by the acid-base properties of the components of the radical ion pairs (exiplexes).
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 41–48, January, 1988.  相似文献   

8.
1.  The rate constant for the destruction of radical pairs decreases with increase in the distance between the traps of the H atom.
2.  A mechanism was proposed for the destruction of radical pairs, according to which the main channel for hydrogen transfer during annealing does not coincide with the channel for phototransfer when the RP are formed.
3.  Based on a formally kinetic analysis for a stepwise rate, distribution parameters based on the activation energies were found for the deuterated and undeuterated samples. A superficial estimate was made of the change in the activation energy when the distance between the unpaired electrons in the radical pairs is changed by one unit of length.
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9.
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.
For previous communication, see [1].  相似文献   

10.
1.  A specific geminal interaction in the OCCl triad, which is weakened in comparison to the corresponding ethers, appears in the mono--chloro esters RCOOCClR1R2.
2.  All the mono--chloro esters exist in a synclinal conformation with respect to the O-Csp3 bond with a ClCOC(O) dihedral angle equal to 70–90°.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 69–73, January, 1989.  相似文献   

11.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1040–1047, May, 1988.  相似文献   

12.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 269–275, February, 1989.  相似文献   

13.
1.  In liquid-phase reactions chlorine fluorosulfate is a more effective reagent for replacement of a chlorine atom in Freons by the fluorosulfate group than peroxydisulfuryl difluoride.
2.  These processes and the reaction of peroxydisulfuryl difluoride with carbon monoxide in the liquid phase take place only in the presence of fluorosulfonic acid.
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14.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2566–2575, November, 1988.  相似文献   

15.
1.  The catalyzed reaction of 2-substituted furans with dimethyl diazomalonate in the presence of Rh(OAc)2 at 20°C gives the dimethyl esters of the Z-isomers of substituted 5-oxopenta-1,3-diene-1,1-dicarboxylic acids (yields up to 100%), which undergo smooth thermal rearrangement (150°C) to the E-isomers. 2,5-Disubstituted furans react to give the products of insertion of bis(methoxycarbonyl)carbene into the -C-H bond of the furan ring, in addition to the esters of the oxodienoic acids.
2.  Analogous reactions of 2-alkenylfurans with dimethyldiazomalonate afford both adducts of the carbene to the exocyclic double bond, and products of the reaction of the carbene with the furan ring (diesters of the oxotrienedicarboxylic acids). Introduction of methyl substituents into the -position of the vinyl group in the starting 2-alkenylfuran modifies the course of the reaction to give predominantly (or exclusively) the oxotrienoate esters.
3.  The reaction of 2-propenylfuran with dimethyl diazomalonate in the presence of Rh(OAc)2 to give the 3-methyl-2-(2-furyl)cyclopropane-1,1-dicarboxylate ester has been found to be fully stereoselective.
4.  The structures of the oxodienedicarboxylate esters formed in the reaction of furans with dimethyldiazomalonate, and of their thermal rearrangement products, have been confirmed by x-ray diffraction analysis, in the cases of the dimethyl esters of Z-7-methyl-5-oxoocta-1,3,6-triene-1,1-dicarboxylic and E-5-oxohexa-1,3-diene-1,1-dicarboxylic acids.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2340–2347, October, 1988.  相似文献   

16.
1.  The N-chloro-N-nitroamides of arylsulfonic acids react with olefins to give a mixture of the N- and O--chloroalkylation products of the nitroamides.
2.  When arylsulfonic acid N-chloro-N-nitroamides react with monosubstituted ethylene derivatives the nitroamide group adds to the least hydrogenated carbon atom of the multiple bond.
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17.
1.  Claisen rearrangement of N-alkenyl- and N-cycloalkenyltetrahydroquinolines by treatment with Lewis and Bronsted acids affords 8-alkenyl- and 8-cycloalkenyltetrahydroquinolines in yields of up to 85%.
2.  Cyclization of the compounds obtained by treatment with polyphosphoric acid, palladium complexes, or UV irradiation has given some tri- and tetracyclic compounds.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1852–1857, August, 1988.  相似文献   

18.
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.
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19.
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.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 365–372, February, 1989.  相似文献   

20.
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.
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