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1.
| 1. | The existence of synergism is demonstrated; the activity of Pd-Tc/carrier catalysts in the dehydrogenation of hydrocarbons considerably exceeds that of monometallic catalysts. The most active catalysts are those with PdTc ratios from 11 to 23. |
| 2. | In terms of reactivity on Pd-Tc catalysts, the hydrocarbons are arranged as follows: cyclohexene > cyclohexane > methylcyclohexane > ethylcyclohexane > n-hexane. |
| 3. | Activity in the dehydrogenation of cyclohexane varies as follows: Pd-Tc/-Al2O3 > Pd-Tc/MgO > Pd-Tc/TiO2 > Pd-Tc/Y2O3 > Pd-Tc/SiO2. |
| 4. | A decrease in CO chemisorptive capacity on bimetallic catalysts compared to monometallic catalysts is established. |
2.
L. F. Godunova E. S. Levitina E. I. Karpeiskaya E. I. Klabunovskii Yu. L. Yagupol'skii M. T. Kolycheva 《Russian Chemical Bulletin》1989,38(2):351-354
| 1. | Catalytic reductive aminolysis of the azalactones of N-acyl-p-difluoromethoxy--aminocinnamic acid in dimethoxyethane, isopropanol, and tert-butanol proceeds stereoselectively, leading to the -phenylethylamides of N-acyl-p-difluoromethoxyphenylalanine with a 3–55% excess of the S,S-diastereomer. |
| 2. | Replacement of dimethoxyethane by isopropanol or tert-butanol leads to an increase in the stereoselectivity of the process. |
| 3. | Hydrogenation of the S-(+)--phenylethylamide of N-acyl-p-difluoromethoxy--aminocinnamic acid proceeds stereoselectively, and leads to production of the -phenylethylamide of N-acyl-p-difluoromethoxyphenylalanine with a 9–18% excess of the R,S-diastereomer. |
3.
E. S. Isaeva N. E. Dontsova N. P. Petukhova E. N. Prilezhaeva E. N. Gur'yanova 《Russian Chemical Bulletin》1989,38(7):1419-1422
| 1. | The relatively small values of the dipole moments of tetrakis(alkylthio)- and also of tetrakis(alkylsulfonyl)ethylenes indicate a certain structural symmetry of the molecules, and are possibly due to divergence of the SR groups from the plane of the central fragment. |
| 2. | In the reaction with group III metal halides, tetrakis(alkylthio)ethylenes display properties of polyfunctional electron-donors giving complexes with a 11, 12 composition and others with a more complex stoichiometry. Heats of formation and dipole moments of these complexes have been determined. |
4.
| 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. |
5.
Reaction of bis (π-allyl)dipalladium dichloride with diethylcadmium and bis (triethylgermyl) cadmium
G. A. Razuvaev G. A. Domrachev V. T. Bychkov S. N. Titova I. V. Lomakova 《Russian Chemical Bulletin》1976,25(9):1984-1986
| 1. | The reaction of bis (-allyl)dipalladium dichloride with diethylcadmium, bis(triethylgermyl)cadinium, and bis (triethylgermyl)mercury was studied. The reaction proceeds with the initial formation of the 11 adduct and subsequent exchange reaction. |
| 2. | The decomposition of the intermediate [AllPdR] compounds depends on the nature of the E group. When R=Et the decomposition proceeds via the intermediate formation of the -olefin complex and the subsequent liberation of ethylene. When R=Et3Ge the decomposition includes the disproportionation reaction and the radical decomposition of the disproportionation products. |
6.
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. |
7.
V. M. Denisov E. Yu. Melenevskaya V. N. Zgonnik A. I. Kol'tsov V. M. Sergutin 《Russian Chemical Bulletin》1976,25(9):1868-1870
| 1. | The effect of dilution with inert solvents on the dissociation of BuLi complexes with the electron donors, OMe2, OEt2, NEt3, and SEt2 has been studied through PMR spectra. Data concerning the stability of donor — acceptor complexes has been obtained. |
| 2. | Interaction of BuLi with dimethyl ether leads to the formation of a 11 complex. Fewer than four molecules of the donor add to the tetramer in other cases. |
8.
Two polymorphic modifications of (BEDT-TTF)2IC12 crystals with metallic and semiconductor properties
Buravov L. I. Zvarykina A. V. Ignat'ev A. A. Kotov A. I. Laukhin V. N. Makova M. K. Merzhanov V. A. Rozenberg L. P. Shibaeva R. P. Yagubskii É. B. 《Russian Chemical Bulletin》1988,37(9):1815-1820
| 1. | By chemical and electrochemical methods we have obtained as single crystals two polymorphic modifications ( and ') of the radical-cation salt of composition (BEDT-TTF)2IC12. |
| 2. | We have studied the electrical conductivity, the thermoelectric and magnetic properties of both phases. We have found that the phase is a metal (293 – 200 ohm–1.cm–1) and the ' phase is a semiconductor (293 –= 10–2 ohm–1 · cm–1). |
| 3. | We have established correlations between the structural and physical properties of - and '-(BEDT-TTF)2ICl2. |
9.
Mirzayanova M. N. Medvedeva I. V. Fedulova I. E. Egorov Ts. A. Khorlin A. Ya. 《Russian Chemical Bulletin》1976,25(7):1520-1524
| 1. | The synthesis has been accomplished of the methylamides of-N-benzoyl--(N-methyl-N-phenyl-thiocarbamyl)propionic ] and butyric acids, which under the conditions used for dehydration of polypeptide chains by the Edman method through treatment with trifluoroacetic acid were converted into cyclic derivatives of hexahydropyrimidine. |
| 2. | Derivatives of D, L-erythro- and D, L-threo-diaminobutyric acid were readily and reversibly converted into one another under the action of acidic and basic reagents. |
10.
V. I. Kadentsev B. I. Maksimova O. S. Chizhov L. A. Yanovskaya 《Russian Chemical Bulletin》1989,38(4):874-876
| 1. | The -lactone is more stable than the -lactone both relative to electron impact and upon chemical ionization. |
| 2. | The major pathways for fragmentation upon electron impact for the -lactone are related to decomposition of the cyclohexane ring, while, in the case of -lactone, fragmentation of the oxygen-containing part of the molecule also occurs in addition to these processes. |
11.
V. A. Ermolaeva G. A. Marchenko V. I. Markovskii V. I. Slovetskii S. S. Novikov 《Russian Chemical Bulletin》1976,25(12):2495-2498
| 1. | Study has been made of the IR spectra of N--polynitroalkylhydrazine derivatives, band assignments being made for stretching vibrations in the NH, C=O, and NO2 groups. |
| 2. | Integral intensities for NO2 antisymmetrical stretching absorption bands are additive. Splitting of these bands is characteristic of nitro compounds containing a hydrazine radical in the -position with respect to the nitro group. |
| 3. | It has been shown that intermolecular hydrogen bonding exists in the N--polynitro-alkylhydrazines, in the crystalline state and in concentrated solution. |
12.
L. S. Zakharov E. I. Goryunov S. T. Ioffe L. L. Morozov T. M. Shcherbina M. I. Kabachnik 《Russian Chemical Bulletin》1976,25(8):1727-1731
| 1. | The catalytic phosphorylation of -polyfluoralkylbenzyl alcohols with an excess of phosphoryl chloride in the presence of a catalyst in the form of an alkali- or alkaline-earth metal chloride has been studied. |
| 2. | Depending on the substituent in the benzene ring, the reaction leads to the formation of -polyfluoralkylbenzyl dichlorophosphates or (in the presence of an electron-donating substituent) to the formation of the corresponding simple benzyl ethers. |
13.
A. N. Nesmeyanov N. E. Kolobova I. B. Zlotina B. V. Lokshin I. F. Leshcheva G. K. Znobina K. N. Anisimov 《Russian Chemical Bulletin》1976,25(5):1093-1097
| 1. | The reaction of tetrakis(trifluoromethy1)allene with -C5H5Fe(CO) 2 – and Re(CO) 5 – gives -complexes. |
| 2. | On irradiation and heating, the -complex of iron is converted into the -allylidene complex. |
14.
| 1. | Substituted thiazoles are formed when N-acyl--aminoketones are heated with thioacetic acid and ZnCl2 in ether dioxane or ethyl acetate. |
| 2. | The reaction of acetamidoacetone with thioacetic acid and ZnCl2 at 20° leads to 2,5-dimethyl-5-acetylmercapto-2-thiazoline. |
| 3. | -Formamidoketones are formed when-aminoketone hydrochlorides are heated with orthoformic ester. |
15.
| 1. | An x-ray diffraction structural analysis has established the structure of the merocyanine form of 1-hydroxyethyl-3,3-dimethyl-6-nitro-8-methoxyspiro(indoline-2,2-[2H-1]-benzopyran). The introduction of an 8-OCH3 substituent into the benzopyran fragment reduces the zwitter-ionic nature of its complex hybrid structure and increases the contribution of the less polar quinoid form, leading to increased stability of the photochromic systems derived from this type of spiropyrans relative to side-reactions. |
| 2. | The molecules in this crystal structure form strong chains due to Van der Waals interactions, which are linked by hydrogen bonds. The formation of such chains and their mutual association largely determines the structure of the absorption spectra of this compound in the solid phase and solution. |
16.
A. M. Turuta A. V. Kamernitskii T. M. Fadeeva A. Pabinger V. S. Bogdanov S. V. Lindeman Yu. T. Struchkov 《Russian Chemical Bulletin》1988,37(10):2156-2161
| 1. | The transformation of 21-0,N-isopropylidene derivatives of 16,17-epiminopregn-5-ene-2,21-diol-20-one into 20-0,N-isopropylidene derivatives of 16,17-epiminopregn-5-ene-3,20-diol-20-one was discovered, and, based on this, a new variant of the synthesis of 16,17-epiminopregn-5-ene-3,21-diol-20-one-3,21-diacetate was proposed. |
| 2. | A new class of steroids with additional tetrahydrofuran and 1,3 -imidazolidine-2thione rings E and F, respectively, was synthesized. |
17.
V. N. Odinokov V. K. Ignatyuk G. A. Tolstikov Yu. B. Monakov A. A. Berg A. M. Shakirova S. R. Rafikov A. A. Berlin 《Russian Chemical Bulletin》1976,25(7):1475-1481
| 1. | Liquid cis-1,4-oligodien-1,3-, -glycols have been prepared by the partial ozonolysis of cis-1,4-polydienes-1,3 in inert solvents containing methanol as an active additive in the amount of 1 to 10 moles per 1 mole of ozonide and subsequent reduction of the peroxide ozonolysis products by LiAlH4. |
| 2. | A method is proposed for the determination of the molecular weights of the oligomeric ,-glycols by use of the PMR spectra of their bis(trimethylsilyl) ethers, and the molecular weight distributions of the oligomeric, -glyeols obtained have been established. |
18.
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. |
19.
A. M. Kritsyn L. I. Kolobushkina S. N. Mikhailov V. L. Florent'ev 《Russian Chemical Bulletin》1976,25(2):384-387
| 1. | 9-(3-Aminopropyl)adenine, racemic 9-(2-hydroxy-3-amitiopropyl)adenie and its (R)-enantiomer, and 9-(2-hydroxy-3-methylaminopropyl)adenine were synthesized. |
| 2. | A study was made of the NMR spectra of the reaction products of the -tosyloxyalkyl derivatives of uracil and thymine with ammonia and methylamine. Theories were expressed regarding the structure of the formed compounds. |
20.
T. Ya. Medved' N. M. Dyatlova V. P. Markhaeva M. V. Rudomino N. V. Churilina Yu. M. Polikarpov M. I. Kabachnik 《Russian Chemical Bulletin》1976,25(5):992-997
| 1. | New organophosphorus complexing agents were synthesized: ethylenediamino-N,N'-diethylphosphonic, N,N-dimethylethylenediamino-N,N-dimethylphosphonic, and N,N-dimethylethylenediamino-N, N-diethylphosphonic acids and also the iodomethylate of the last acid. |
| 2. | The acid dissociation constants for these compounds and the stability constants for their complexes with nickel, copper, dysprosium, and uranyl ions were determined. |