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1.
L. S. Isaeva G. I. Drogunova A. S. Peregudov D. N. Kravtsov 《Russian Chemical Bulletin》1988,37(1):153-157
| 1. | New cationic o-tolyl and o-fluorophenyl complexes of Ni containing Ph3P, MeCN, or THF ligands have been synthesized. |
| 2. | Reaction of these compounds with potassium carboxylates gave the novel o-tolyl and o-fluorophenylbis(triphenylphosphinyl)nickel carboxylates. |
| 3. | According to19F NMR data o-tolylbis(triphenylphosphinyl)nickel p-fluorobetizoate contained a highly polarized Ni-O bond. |
2.
Presently, a large variety of layered materials are synthesized that are able to intercalate neutral guest molecules or to exchange inorganic and organic ions for interlayer ions. Several of these materials are also found as minerals.The intracrystalline reactivity of a few selected compounds will be described and compared to clay minerals:
相似文献
| – | - intercalation into crystalline silicic acids; |
| – | - reactions of phosphates, arsenates, and sulfates; |
| – | - reactions of titanates, niobates, and molybdates with long chain alkylammonium ions, and |
| – | - anion exchange properties of double hydroxides. |
3.
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. |
4.
| 1. | A new type of sorbents, containing SH groups, was obtained by the modification of aminooxy adsorbents. |
| 2. | The obtained sorbents were used for the covalent immobilization of biologically active compounds with the formation of C-S, C-Hg-S, and S-S bonds. |
5.
| 1. | The strong bathochromic shift of the absorption bands of aminoazo compounds in acid medium is due to the formation of a cation of quinoid structure. |
| 2. | Aminoazo compounds are weak NH acids in aprotic polar solvents, and they form the corresponding mesomeric anions in the presence of alkalis. |
| 3. | The synthesized aminoazo compounds are very weak NH acids, and electron-donor substituents weaken the acid properties of the amino group, while electron-acceptor substituents intensify them. |
6.
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. |
7.
| 1. | Following the CNDO/2 approximation to the SCF MO LCAO method, electronic parameters have been calculated for the molecules and ions of various nitro compounds. |
| 2. | Calculated values of the dipole moment and enthalpy of atomization proved to be in satisfactory agreement with the experimentally determined values, the maximum deviation between them amounting to 1.4% for the aromatic systems. |
| 3. | The nitro compound parameters most sensitive to change in the intramolecular interaction are the C-N bond energy and the charges on the carbon and halide atoms. |
8.
| 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. |
9.
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. |
10.
| 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. |
11.
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. |
12.
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. |
13.
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. |
14.
B. A. Arbuzov I. M. Khamatullina S. G. Vul'fson A. M. Kamalyutdinova A. N. Vereshchagin 《Russian Chemical Bulletin》1976,25(11):2296-2300
| 1. | Polarizability parameters have been obtained for the C6H5-C group in benzylidene bromides, and it has been shown that the bromine atom in these compounds interacts with the aromatic system. |
| 2. | The conformations of the nonsterically hindered benzylidene bromides are close to those in which the ring plane is shielded by the C-Br bond. |
15.
N. L. Zaichenko A. V. Lyubimov V. S. Marevtsev M. I. Cherkashin 《Russian Chemical Bulletin》1989,38(5):941-945
| 1. | The PMR spectra of the closed forms of spironaphthopyran and spironaphthooxazine were interpreted. The PMR spectra of the photoinduced forms of these compounds were obtained for the first time. |
| 2. | The open form of spironaphthooxazine in nonpolar solvents was found to have the quinoid structure of one of the trans isomers, while there is a shift in the equilibrium toward the bipolar structure in polar solvents. |
16.
| 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. |
17.
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. |
18.
| 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. |
19.
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. |
20.
| 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. |