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1.
Kh. M. Minachev Ya. I. Isakov V. P. Kalinin Yu. S. Akhmetov 《Russian Chemical Bulletin》1976,25(5):1041-1048
| 1. | The catalytic properties of the Ni forms of various types of synthetic zeolites in the reaction of benzene with ethylene are determined by their structure, composition, and conditions under which they are used. |
| 2. | The NiNaA zeolites accelerate only the dimerization of C2H4, and are inactive in the alkylation of C6H6 with olefins. From benzene and ethylene it is possible to obtain on NiX and NiY either predominantly sec-butylbenzene (SBB) (selectivity 80–86%) or SBB and butenes in approximately equal amounts. |
2.
| 1. | Polarizability parameters have been determined for the selenocyanate group. |
| 2. | Selenobenzene cyanate, and derivatives of this compound with donor substituants in the p position, have planar conformations; introduction of acceptor substituents breaks down the coplanarity of the C6H4-SeCN fragment. |
3.
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. |
4.
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. |
5.
N. F. Yudanov E. G. Boguslavskii I. I. Yakovlev S. P. Gabudar 《Russian Chemical Bulletin》1988,37(2):200-203
| 1. | A method has been developed for the intercalation of solid substances from solutions in organic solvents into graphite fluoride C2Fx. |
| 2. | Molecules of inserted paramagnetic copper complexes and nitroxyl radicals assume oriented positions between the structural layers in graphite fluoride. |
| 3. | The planes of molecules of bis-chelate Cu(II) complexes with acetylacetone, o-hydroxyquinoline, and phenylsalicylaldimine were determined to lie parallel to the C2Fx planes. |
| 4. | A method has also been suggested for the preparation of samples from C2Fx·yA compounds with a higher degree of texturizing (more nearly complete orientation) than can be achieved by pelletizing. |
6.
| 1. | The values of log (CB/CBH +) of 4-, 2-, and 2,6-dichloro-4-nitroanilines in the H2O-HCl--butyrolactam (BL) system were obtained at 25°C, at various BL and HCl concentrations under conditions wherein BL is either nonionized, partially or completely ionized. |
| 2. | It was shown that if BL is either completely nonionized or completely ionized, the Ho of an aqueous solution and the Ho S of a solution of HCl in a H2O-BL mixture are equal at the same H5O2 + concentrations on a molar ratio scale. |
7.
| 1. | A series of C-functional derivatives of (3)-1,2-dicarbaundecaborate was synthesized and some of their properties were studied. |
| 2. | Apparent ionization constants of acids of the (3)-1,2-dicarbaundecaborate series were measured and it was found that they are very weak carboxylic acids. |
| 3. | Upon reaction with excess LiA1H4, under mild conditions the carbonyl, *20c \CH(OH) / \begin{array}{*{20}c} \backslash \\ {CH(OH)} \\ / \\ \end{array} , and CH2OH groups of dicarbaundecaborate ketones and alcohols are reduced to CH2 and CH3 groups, respectively. |
| 4. | The effect of Grignard reagent on ketones and esters of the dicarbaundecarbprate series was studied and it was established that the composition of reaction products depends both on the steric hindrance of the carbonyl group and on the electron-donating effect of the (3)-1,2-dicarbaundecaborate substituent. |
8.
| 1. | The structure of the isocyanate functional group in organic isocyanates in the crystalline state is analogous to that in the gas phase. |
| 2. | The isocyanate group (H)C1-N=C2=O exists in a trans conformation in all three of the isocyanates studied. |
| 3. | The lamellar packing characteristic of ,-naphthalenediisocyanate molecules may be assigned to a structural subclass of naphthalene ¯1, namely, P(x)P21/b. |
9.
| 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. |
10.
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. |
11.
| 1. | The decomposition of hydroxyhydrotrioxides is described by a first order equation. The electron-donor substituents increase the stability of the hydrotrioxides. |
| 2. | There is a compensational effect for the preexponential factors and energies of activation of thermal overall decomposition of (CH3)2C(OH)OOOH in solvents CHCl3, CCl4. CH3CN, n-C6H14, (C2H5)2O and in C2H5OH-H2O mixtures. |
| 3. | The influence of the solvent on the rate constant of the overall decomposition of (CH3)2C(OH)OOOH is described for the range when the Koppel'-Pal'm equation holds. |
12.
T. T. Vasil'eva 《Russian Chemical Bulletin》1976,25(9):1910-1913
| 1. | Addition of mercaptans of 3,5,5-trichloro-1,3-pentadiene proceeds with the formation of products of 1,2 and 1,4 addition. |
| 2. | Arguments are presented in favor of rearrangement of the CHCl2HCCl=CHCH2SC4H9 radical to the ClHCHC1CCI=CHCH2SC4H9 radical during addition of butyl mercaptan to 3,5,5, -trichloro-1,3-pentadiene. |
13.
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. |
14.
| 1. | The IR and Raman spectra of the methyl selenophosphonates and methyl selenophosphinates: (CH3O)2P(Se)CH3, CH3OP(Se) (C2H5)2, and CH3OP(Se) (C6H5)2 were studied in various phase states and in solvents, and with a variation in the temperature. The vibration bands of the P=Se group were assigned. |
| 2. | A thermodynamic equilibrium of at least two steric forms of the molecule was detected in the first two compounds. The isomers arise as the result of one methoxy group rotating from the gauche position with respect to the P=Se bond to the trans position, with a gauche orientation of the other groupings. |
| 3. | The relative amount of the isomers in the mixture and the thermodynamic parameters of the equilibrium were determined. |
| 4. | The steric conditions created by the two aryl radicals in the third compound lead to a stabilization of one predominant conformer in all of the states of the compound, with a gauche orientation of the OCH3 with respect to the P=Se bond. |
15.
| 1. | The interaction of borohydrides of the alkali and alkaline-earth metals (Li, Na, K, Mg, Ca, and Sr) with dihorane in diglyme medium at 0° and an initial pressure of B2H6 no higher than 600 mm was studied. |
| 2. | It was established according to the data of the IR spectrum that all the investigated borohydrides, with the exception of calcium borohydride, react with diborane in diglyme with the formation of diborohydrides. |
| 3. | In the interaction of calcium borohydride with B2H6, the addition of borane (BH3) occurs at one of the two BH4 groups, with the formation of the compound CaBH4B2H7 ·2DG. |
| 4. | LiB2H7 · 2DG, NaB2H7 · 2DG, and CaBH4B2H7 · 2DG were isolated in the individual state. |
16.
| 1. | The authors have studied the formation of electron and hole paramagnetic centers in gamma-irradiated magnesium hydroxide and oxide with various degrees of dehydration. |
| 2. | Rise in the temperature of preliminary heat treatment of the magnesium oxide causes an increase in the radiation-chemical yield of FS + centers and a decrease in that of V su – centers. |
| 3. | The thermal stability of paramagnetic centers in magnesium oxide increases as the hydroxyl group content decreases. |
17.
L. A. Leites L. E. Vinogradova V. T. Aleksanyan S. S. Bukalov 《Russian Chemical Bulletin》1976,25(11):2311-2317
| 1. | Complete vibrational spectra have been obtained for the icosohedral carboranes O- and M-B10H10C2H2 and O-, M-, and p-B10Cl10C2H2, and certain frequencies identified. |
| 2. | The spectra of these compounds proved to be more simple than could have been anticipated from an application of the selection rules for the symmetries in question. It is suggested that certain vibrations in these molecules follow the higher effective A12X12-I symmetry of the hypothetical icosahedron. |
18.
Yu. N. Belokon' V. M. Belikov V. A. Karginov V. I. Tararov 《Russian Chemical Bulletin》1976,25(11):2390-2395
| 1. | Three complexes of sodium bis[N-3-substituted-salicylidene-S-valinato]cobaltate(III) were synthesized where the salicylaldehyde residue was substituted in position 3 with the NO2, i-C3H7, and t-C4H9 groups. The (SS)- and (SS)-diastereomers of the complexes were separated and their structure and configuration were demonstrated by elemental analysis and physical methods. |
| 2. | The stereoselective effects in these compounds were studied and it was shown that by varying the bulk and electronic effects of groups in the salicylaldehyde ring (from 5-NO2 to 3-t-C4H9) the relative energy of diastereomers can be changed in the interval of 2.6 kcal/mole. |
| 3. | Stereoselective effects were studied in the complexes potassium - and -bis[N-salicyliden-S-alaninato ]cobaltate(III) and potassium - and -bis[N-salicylidene-S-valinato]cobaltate(III) in various solvents and it was shown that the solvent has at least no less an effect on the energy difference of diastereomers than do the substituants introduced into the complex molecule. |
| 4. | The energy difference of diastereomers in a series of alcohols correlates with the dielectric constant of the solvent, which indicates the important role of electrostatic interactions in complexes. |
19.
G. I. Sarapulova L. I. Volkova B. A. Gostevskii V. A. Lopyrev Yu. L. Frolov 《Russian Chemical Bulletin》1988,37(6):1162-1165
| 1. | The effect of the C6F5 group on the C=0 frequency of C6F5COR compounds depends on the structural features of the R fragment; for ketones, amides, and hydrazides there is steric inhibition of resonance in the C6F5CO group and an increase in the role of the inductive effect from C6F5. |
| 2. | In N-dimethylpentafluorobenzamide the decrease in resonance is compensated by p,-conjugation in the CON group, and the inductive effect of the C6F5 ring appears to be weaker than in pentafluoroacetophenone. |
| 3. | The presence of the second nitrogen atom and the change in relative orientation of the unshared electron pair when affected by substituents at N1 and N2 in pentafluorobenzahydrazide molecules leads to an increase in the torsion angle in C6F5-CO in comparison to N-dimethylpentafluorobenzamide, which increases the -I effect of C6F5 on C=0 in pentafluorobenzhydrazides. |
20.
| 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. |