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1.
| 1. | The previously unknown aminooxyalkylcelluloses have been synthesized by alkylation of cellulose with N-substituted -haloalkylhydroxylamines. |
| 2. | The prepared aminooxyalkylcelluloses are weak ion-exchangers, readily react with many classes of organic compounds, and are stable during storage. |
| 3. | Methods have been developed for the preparation of aminooxyalkylcelluloses with different lengths of the pendant H2NO group on the polysaccharide framework. |
| 4. | Sorbents were prepared, based on the aminooxyalkylcelluloses, which contained a covalently bonded coenzyme (pyridoxal-5-phosphate), a substrate (-ketoglutaric acid) and functional groups, able to react with certain functional groups of biopolymers. |
2.
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. |
3.
L. A. Rozov Yu. V. Zeifman N. P. Gambaryan Yu. A. Cheburkov I. L. Knunyants 《Russian Chemical Bulletin》1976,25(12):2560-2566
| 1. | Depending on the nature of the substituent in the 2 position, l-fluoro-l-(-hydrohexafluoroisopropyl)ethylenes are dehydrofluorinated to either allenes or 1,3-dienes. |
| 2. | It was shown that allylic substitution is possible in the reactions of perfluoroisobutylene with carbanions; the mutual transformations of the allyl and vinyl isomers were studied. |
| 3. | The perfluoroalkenylation product was obtained when perfluoroisobutylene is reacted with ketene acetal. |
4.
| 1. | Alkylarylketiminoboranes react with nitriles to form boron -diiminates, whose structure has been determined by UV, IR, PMR, and boron-11 NMR spectroscopy. |
| 2. | Depending on their structure, boron -diiminates are hydrolyzed in an acid medium with the formation of either boron -diketonates, or -diketones. |
| 3. | During the reaction of boron -diiminates with HCl or HBF4, boronium salts are formed with -diimines as ligands. |
5.
Sviridov V. D. Chkanikov N. D. Korbukh I. A. Kolomiets A. F. Fokin A. V. 《Russian Chemical Bulletin》1989,38(7):1519-1522
| 1. | 4-Aminopyrimidines react with hexafluoroacetone to give pyrimidooxazines and pyrimidooxadiazines. |
| 2. | An account is given of the C5 aminoalkylation of 1,3-dimethyluracil by the trifluoroacetylimines of hexafluoroacetone and of the methyl ester of trifluoropyruvic acid. |
6.
N. D. Chkanikov V. L. Vershinin M. V. Galakhov A. F. Kolomiets A. V. Fokin 《Russian Chemical Bulletin》1989,38(1):113-119
| 1. | Nonsterically hindered primary arylamines react with hexafluoroacetone benzenesulfonyl- and trifluoroacetylimines to give stable gem-diamino compounds. |
| 2. | The presence of substituents at the nitrogen of the arylamine destabilizes these gem-diamino compounds, with the formation of C2- and C4-alkylation products. With hexafluoroacetone trifluoroacetylimine, C2-alkylation is accompanied by heterocyclization to give 1-substituted 2,4,4-tris(trifluoroacetyl)-1,4-dihydroquinazolines. |
| 3. | N,N-Dialkylanilines are regioselectively alkylated at C4. |
7.
| 1. | Study has been made of the kinetics of the-elimination of alcohol from 3-carbethoxy-4-ethoxy-2-pentanone in benzene and under the catalytic action of acetic acid. |
| 2. | This reaction involves formation of a complex between substrate and acetic acid. |
| 3. | The equilibrium constant for the reaction of forming the complex between substrate and acetic acid, and the rate constant for complex formation, have both been determined. |
8.
| 1. | It has been shown by PMR spectroscopy that in a solution of RYbI there exists an equilibrium similar to that established by Schenk for Grignard reagents. |
| 2. | The compound formed by the action of an equimolar mixture of PhI and LiI on Yb metal in THF differs in reactivity from PhYbI in its reaction with CF2=CF2. |
| 3. | The reaction of PhSmI with 1,2,2-trifluorostyrene differs from the reactions of PhEuI and PhYbI in that it gives an equimolar mixture of the cis and trans isomers of 5,6-difluoro-4,6-diphenyl-5-hexene-1-ol. |
| 4. | PHCeI does not react with 1,2,2-trifluorostyrene. However, the organocerium complex formed by the oxidatlve addition of Ce to PhI in the presence of an equivalent quantity of LiI reacts with 1,2,2-trifluorostyrene to form an equimolar mixture of the cis and trans isomers of 5.6-difluoro-4,6-diphenyl-5-hexene-1-ol. |
9.
| 1. | The condensation of 1,2-hydroxylamino oximes with biacetyl leads to 1-hydroxy-2-acetyl-2,4,5,5-tetrasubstituted 3-imidazoline 3-oxides. |
| 2. | When 1-hydroxy-2-acetyl-2,5,5-trimethyl-4-phenyl-3-imidazoline 3-oxide is oxidized the CH3CO group is cleaved to give the 5H-imidazole 1,3-dioxide. |
| 3. | Stable nitroxyl radicals were obtained when the 1-hydroxy-2-oximiaoethyl-2,4,5,5-tetrasubstituted 3-imidazoline 3-oxides are oxidized. |
10.
| 1. | N-Ethyl and N-isopropyl-3-piperidones were synthesized and the stereochemistry of their reduction was studied. |
| 2. | The dependenceof stereochemistryof a series of reactions at the carbonyl center on bulk of the substituent on nitrogen was established. |
| 3. | Pure a- and e-epimers of N-ethyl- and N-isopropyl-3-piperidols were separated. |
11.
| 1. | In phosphoryl compound + HCCl3 + CCl4 systems, hydrogen-bonding complexes form with chloroform with 11 and 1 2 compositions. |
| 2. | The enthalpy of formation of a hydrogen bond between a phosphoryl compound and HCCl3 has been evaluated, and it correlates linearly with the shift in the overtone in the range measured. |
| 3. | A linear correlation of -H with the sum of the Taft constants of the substituents on the phosphorus has been found. |
12.
| 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. |
13.
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. |
14.
V. I. Bregadze A. Ya. Usyatinskii V. A. Antonovich N. N. Godovikov 《Russian Chemical Bulletin》1988,37(3):570-573
| 1. | Carboranyl derivatives of aluminum, gallium, and indium, containing a Ccarb-M bond, were obtained. |
| 2. | Carboranes react with trimethylgallium etherate in the presence of tetramethyl-ethylenediamine to give gallium-containing dicarbaundecaborate ions. |
15.
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. |
16.
Zh. A. Krasnaya T. S. Stytsenko V. I. Avdeeva D. Ya. Shagalova 《Russian Chemical Bulletin》1989,38(1):80-86
| 1. | A series of tetracyanopolymethines has been synthesized by condensation of aminals and aminal-acetals of conjugated -dimethylaminoaldehydes with malonodinitrile. |
| 2. | These tetracyanopolymethines can be used as the anionic components in cation-anion cyanine dyes. |
| 3. | The electronic absorption spectra of these newly synthesized dyes were studied in both polar and nonpolar solvents. Specific cation-anion interaction and complex formation has been shown to occur in several of these cation-anion dyes in nonpolar solvents. |
17.
| 1. | Using seven independent methods it was found that the concentration of the active centers on the surface of-Al2O3, which are responsible for the dehydration, is (9±1)×1017 centers/m2. The catalytically active centers are identical with adsorption centers. |
| 2. | A method of calculating the stochiometry, concentration, and thermodynamics of the surface association reactions has been developed. |
| 3. | The first reaction step proceeds according to the associative bimolecular substitution mechanism, with the formation of an associative intermediate compound. The association enthalpy and entropy have been calculated. |
18.
G. V. Kryshtal' G. M. Kursonova V. F. Kucherov L. A. Yanovskaya 《Russian Chemical Bulletin》1976,25(3):652-654
| 1. | ,-Dichloropolyene aldehydes react with acetone cyanohydrin in the presence of triethylamine to give -chloropolyenoic esters. |
| 2. | A new method has been developed for the synthesis of Cl(CH = CH)nCOOR, where n = 2 and 3. |
19.
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. |
20.
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. |