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1.
| 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. |
2.
| 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. |
3.
O. V. Nogina I. A. Uralets G. I. Drogunova N. S. Obezyuk 《Russian Chemical Bulletin》1976,25(1):135-137
| 1. | The reaction of bromine with cyclopentadienylalkoxy(aroxy)titaniums CpTi(OR)3, where R=C2H5, C6H5; Cp=C5H5, C5 (CH3)5, leads to the formation of CpTiBr3 in all cases except that of C5H5Ti(OC2H5)3, and in the case of the aroxy derivatives also to the products where one of the bromine atoms is replaced by the brominated phenols formed in the reaction mixture. |
| 2. | The reaction of bromine with C5H5Ti(OC2H5)3 gives the compound (C2H5O)2TiBr2·C2H5OH. |
| 3. | When C5 (CH3)5Ti(OC6H5)3 is reacted with excess bromine in the presence of UV light the aroxy groups and the hydrogens of the methyl groups in the cyclopentadienyl ligand are replaced by bromine atoms. |
4.
| 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. |
5.
R. Kh. Freidlina A. A. Kamyshova L. A. Zhuravleva E. Ts. Chukovskaya 《Russian Chemical Bulletin》1976,25(9):1897-1900
| 1. | Reductive cyclization of compounds with the CCl2 grouping, ClCH2CH2CCl2CH2CClXR (R=H, CH3; X=CN, CO2CH3) led to the formation of monosubstituted cyclopropanes, cyclo-C3H5CH2CHXR. Under the reaction conditions, the Cl atom in the position to CO2CH3 and CN groups is reduced without taking part in cyclization. |
| 2. | The presence of chloro-substituted C atoms in the direction to the CCl2CH2CHC1 fragment hinders the reductive cyclization of this fragment. |
| 3. | Cyclization by means of the two dichloromethyl groups in the compound CHC12CH2CHC12 does not take place. In this case, the principal reaction route is a stepwise reduction and alkoxylation. |
6.
F. P. Sidel'kovskaya V. A. Ponomarenko M. G. Zelenskaya A. V. Ignatenko O. D. Trifonova É. A. Abdula-Zade A. G. Kechina L. A. Sinitsyna 《Russian Chemical Bulletin》1976,25(3):587-593
| 1. | Some new -oxides were synthesized, which contain a lactam ring in the substituent and have the general structure: where R = H, CH3; OC OC2H5, and Z = CH2, CH2OCH2, (CH2)2OCH2. |
| 2. | It was shown on the example of the synthesized glycidyl ethers that they are capable of forming polymeric products under the influence of nucleophilic agents, and also of adding water, ammonia, and diethylamine under mild conditions. |
7.
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. |
8.
N. P. Rodionov S. G. Mairanovskii V. P. Gul'tyai I. V. Proskurovskaya 《Russian Chemical Bulletin》1976,25(6):1275-1278
| 1. | It was shown on the basis of data on the study of reduction of benzaldehyde to benzyl alcohol with aluminum isopropoxide in isopropanol that introduction of H2O, CH3COOH, and HCl into the reaction mixture promotes a. significant acceleration of the reaction and an increase in the yield of final reaction products. |
| 2. | The most favorable condition for carrying out the indicated reaction is a ratio of equivalents of Al(i-PrO)3 and CH3COOH equal to 2. |
9.
| 1. | A complex of Au(III) containing N-nitrosoamidated optically active propylenediamine, Au{(R)Pn}(R) -H2NCH2CH(CH3)NNO(ClO4)2·H2O and its analog with racemic ligands was obtained for the first time. |
| 2. | An analysis of the observed electronic transitions in the spectra of the optically active complex and their proposed assignment are given based on studies of the absorption and CD spectra. |
10.
S. P. Kolesnikov A. I. Ioffe B. L. Perl'mutter O. M. Nefedov 《Russian Chemical Bulletin》1976,25(4):736-739
| 1. | We have used the extended Hückel method to examine the interaction of singlet methylene with water and found the existence of a molecular complex CH2·H2O with an energy of stabilization of 5.6 kcal/mole and a complex CH2·2H2O with an energy of stabilization of 2.1 kcal/mole, which tends to lose one water molecule during simultaneous approach of the other. |
| 2. | The structure of these complexes is determined by the interaction of the unoccupied methylene p orbital with the lone-pair orbitals of the water molecules. |
11.
I. S. Akhrem R. S. Vartanyan N. M. Chistovalova E. I. Mysov M. E. Vol'pin 《Russian Chemical Bulletin》1976,25(9):1939-1942
| 1. | The compounds of the platinum group metals (Pt, Pd, Rh, Ir) are active in cleaving the Si-Ph and the Si-alkyl bonds. |
| 2. | Some of the compounds of platinum metals (H2PtCl6·6H2O, PtCl4, RhCl3 · 3H2O, Na2IrCl6) have a catalytic effect on the cleavage of Si-C bond. |
12.
K. K. Kalnin'sh 《Russian Chemical Bulletin》1988,37(9):1768-1773
| 1. | A new method of analysis of autocatalytic reactions was developed which permits determining the rate constants of noncatalytic and catalytic reaction pathways with the data from one kinetic curve. |
| 2. | The reverse reaction of acylation has an autocatalytic character. |
| 3. | In comparison to CHCl3, in CH3CN, all of the rate constants increase by 2–4 times, and the noncatalytic reaction pathways are more sensitive to the nature of the solvent. |
13.
| 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. |
14.
Azatyan V. V. Borodulin R. R. Markevich E. A. Rubtsov N. M. Semenov N. N. 《Russian Chemical Bulletin》1976,25(7):1396-1397
| 1. | Flames resulting from chain NCl3 decomposition are propagated through NCl3 + He mixtures lying outside the autoignition region. |
| 2. | The fact that these are essentially isothermal flames is an indication of the important role of positive chain interaction in this process. |
15.
| 1. | 1,2-Oxathiolan-5-one-2-oxides are readily cleaved by nucleophiles (H2O, ROH, HNR2) under mild conditions at the O-CO bond only, with the formation of the -(hydroxysulfinyl)-alkanoic acid derivatives. |
| 2. | 2,1-Benzoxathiol-3-one-1-oxide is cleaved by alcohols at both the O-CO and the O-SO bonds to give the unstable monoesters at the carboxyl and sulfinyl groups. |
| 3. | Unlike 2,1-benzoxathiol-3-one-1-oxide, 1,2-oxathiolan-5-one-2-oxides on boiling with excess alcohols give -(hydroxysulfinyl)alkanoic acid bisesters. |
16.
B. L. Korsunskii G. V. Sitonina B. S. Fedorov F. I. Dubovitskii L. T. Eremenko 《Russian Chemical Bulletin》1989,38(4):710-713
| 1. | The thermal decomposition of N,N-dinitroamines is homogeneous and unimolecular in the gas phase. The limiting step of the process is the rupture of the N-NO2 bond. |
| 2. | The activation parameters of the process imply that the dinitroamine group is more reactive than the mononitroamine group in thermal decomposition. The energy of dissociation of the N-NO2 bond in dinitroamines is 42 kJ/mole less than in mononitroamines. |
| 3. | Nitrogen dioxide and acetaldehyde do not influence the kinetics of thermal decomposition of dinitroamines due to their high reactivity. |
17.
| 1. | The rate constants were calculated for the abstraction of hydrogen from HCCl3 and of bromine from BrCCl3 by CCl3(CH2CHX)n radicals. |
| 2. | The reactivity of CCl3(CH2CH2)n radicals (n=1, 2) depends on the position of the CCl3 group and the chain transfer step makes the major contribution to the chain transfer constants in the telomerization of ethylene with HCCl3 and BrCCl3. |
| 3. | The reactivity of CCl3(CH3CHX) n . radicals (X=H, Me, Cl) in reactions involving replacement with C-H and C-Hal bond cleavage depends on the nature of X. |
18.
In conclusion, let us note the principal results of the calculation.
Institute of Catalysis, Siberian Branch, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 2, pp. 35–41, March-April, 1992. 相似文献
| 1. | On a clean Ni(100) surface, only molecular adsorption of water is realized. Partial dissociation of H2O is thermodynamically allowed process; however, dissociation of water is impossible because of kinetic limitations. |
| 2. | Modification of the nickel surface by oxygen stabilizes the donor-acceptor pair (H2O/O) on the surface and removes the kinetic limitation in decomposition of water, through a substantial reduction of the activation energy of dissociation. |
| 3. | The promoting role of oxygen is manifested in an increase in the nonuniformity of electron density on the nickel surface in the vicinity of the [Ni]–OH2 bond, which makes it possible to open up a new channel of the reaction in which a high degree of energy compensation in the water dissociation reaction is possible. |
19.
| 1. | The complexes of Pd(acac)2 and Pd(OAc)2 with triphenylphosphine catalyze the telomerization of isoprene with water in the presence of CO2, which leads to the formation of isomeric dimethyloctadienols. |
| 2. | The complexes of Pd(acac)2 and Pd(OAc)2 with tricresyl phosphite catalyze the formation of the isomeric dimethyloctadienol acetates from isoprene and CH3COOH. |
| 3. | In acetone the complexes of Pd(acac)2, Pd(OAc)2 with triphenylphosphine smoothly and almost completely dimerize isoprene to 2,7-dimethyl-1,3,7-octatriene. |
20.
Ya. T. Éidus A. L. Lapidus V. I. Mashinskii L. L. Krasnova 《Russian Chemical Bulletin》1976,25(6):1261-1264
| 1. | The activity of cobalt-group II metal oxide catalysts in the hydropolymerization reactions of C2-C4 olefins, initiated by CO at 190°, depends on the nature of the oxide and decreases when going from BeO to BaO. |
| 2. | In their reactivity the olefins fall into the order: C2 > C3H6 >-C4H8 > i-C4H8. |
| 3. | The degree of reduction of the cobalt found in the catalyst depends on the nature of the employed oxide and (toes not determine its activity. |