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1.
T. N. Deshko A. V. Kamernitskii G. A. Kogan A. M. Turuta T. K. Ustynyuk T. M. Fadeeva 《Russian Chemical Bulletin》1976,25(12):2524-2528
| 1. | Study has been made of the circular dichroism spectra of 20-ketosteroids containing a three-membered ring (methylene, epoxide, episulfide, or aziridine) in the -position with respect to the keto group. |
| 2. | The observed n* and * transition Cotton effects have been correlated with the preferred conformation of the molecule. |
2.
| 1. | It has been shown that bifunctional agents have high activity in catalyzing -elimination reactions; study has been made of the effect of the concentration of such agents on the specific rate of -elimination from methyl-substituted ethoxy--ketoesters. |
| 2. | Study has been made of the state of 2- and 3-oxypyridines in benzene solution at 80°C. A value has been obtained for the 2-oxypyridine dimerization constant. |
| 3. | A mechanism has been proposed for the action of 2-oxypyridine in catalyzing -elimination reactions, and equilibrium constants and rate constants calculated for the various mechanism steps. The factors responsible for the low catalytic activity of 8-oxyquinoline are discussed. |
3.
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. |
4.
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. |
5.
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. |
6.
| 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. |
7.
A. A. Akhrem A. V. Kamernitskii R. P. Litvinovskaya I. G. Reshetova 《Russian Chemical Bulletin》1976,25(1):150-153
| 1. | We synthesized the 3-acetates of the 23-acetoxy-and 23-carbethoxy-21,24-dinorchola-5,6-diene-3,2 0-diols and studied their dehydration. |
| 2. | The presence of an electron-acceptor grouping at C-23 directs the dehydration toward the formation of 23-caxbethoxy-21,24-dinorchola-5,16,20(22)-trans-trien-3-ol 3-acetate, which is an intermediate product in the synthesis of polyhydroxysteroids. |
8.
L. Kh. Freidlin L. I. Gvinter V. A. Zamureenko L. N. Suvorova 《Russian Chemical Bulletin》1976,25(4):795-797
| 1. | Intermediate enol formation has been registered by deuterium exchange in the hydrogenation products of, -unsaturated ketones on Co/C and Rh/C, indicating 1,4 addition of hydrogen to the enone system. |
| 2. | The presence of 1,4 hydrogen addition to,-unsaturated ketones is determined by the nature of the catalyst; Pd/C does not catalyze this process route. |
| 3. | Modification of Pd catalysts with cadmium changes their orienting action and selectivity in favor of 1,4 hydrogen addition with intermediate enol formation. |
9.
| 1. | The diene condensation of 1-alkoxy-1,3-butadienes with aliphatic aldehydes at high pressures leads to predominate formation of 2-alkoxy-6-alkyl-3-dihydropyrans, corresponding to the endo-orientation of the diene and dienophile in the transition state. |
| 2. | The observed effect is explained by the presence of interaction of the partially protonated hydrogen on the -carbon atom of the aldehyde with the -system of the diene. |
10.
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. |
11.
Z. V. Todres G. Ts. Ovsepyan E. A. Ionina A. Yu. Kosnikov S. V. Lindeman Yu. T. Struchkov 《Russian Chemical Bulletin》1988,37(8):1651-1656
| 1. | o-Dinitrobenzene dianion reacts with p-dimethylaminobenzenediazonium cation to give 2-nitro-4-dimethylaminoazobenzene. |
| 2. | o-Dinitrobenzene anion-radical reacts with benzenediazonium cations bearing a dimethylamino-or nitro-group in the para-position, to give 3-nitro-4-hydroxy-4-dimethylamino-azobenzene and 3,4-dinitro-4-hydroxyazobenzene respectively. |
| 3. | In the case of the 4-methoxybenzenediazonium cation, reaction with the o-dinitrobenzene anion-radical affords 4-methoxy-3-(2-nitrophenyl--azoxy)-4-hydroxyazobenzene, the structure of which has been established by x-ray diffraction analysis. |
| 4. | These azo-compounds are formed in solvents which favor the stability of ion pairs of the dianion or anion-radical of o-dinitrobenzene with potassium cations. Dissociation of the ion pairs results in the occurrence of electron transfer only. |
12.
Zh. A. Krasnaya T. S. Stytsenko V. S. Bogdanov A. S. Dvornikov 《Russian Chemical Bulletin》1989,38(6):1206-1218
| 1. | Dienic-dimethylaminocarbonyl compounds were synthesized containing a Br, OEt, or CN substituent in the -position.-Dimethylamino--cyanodienones are found in the open form and do not cyclize to 2H-pyrans. |
| 2. | The existence of a dynamic equilibrium was established between-dimethylamino--bromodienone (or-dimethylamino--ethoxydienone) and 3-bromo-2-dimethylaminopyran (or 3-ethoxy-2-dimethylaminopyran), which depends on the solvent and temperature. |
| 3. | The equilibrium is shifted toward the 2H-pyran with increasing bulk of the solvent in the -position of the-dimethylaminodienone. |
| 4. | The 2H-pyrans upon the action of UV light undergo reversible dissociation of the C-O bond and isomerize to-aminodienones. |
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.
Kozlovskii A. G. Arinbasarov M. U. Yakovlev G. I. Zyakun A. M. Adanin V. M. 《Russian Chemical Bulletin》1976,25(5):1115-1119
| 1. | An earlier unknown metabolite ofPseudomonas aeruginosa, strain A197, 2-(n-1-heptenyl)-4-quinolone, was isolated. |
| 2. | The main components of the total mixture of alkaloids produced byPseudomonas aeruginosa strain A197 are 2-n-nonyl-4-quinolone (pseudane-IX), 2-n-heptyl-4-quinolone (pseudane-VII), 2-(n-1-nonenyl)-4-quinolone (1pseudene-IX), and 2-(n-1-heptenyl)-4-quinolone (1-pseudene-VII). |
| 3. | The synthesis of 2-(n-1 -heptenyl)- 4 -quinolones was carried out. |
15.
V. I. Reznikov V. Yu. Zel'venskii L. F. Rybakova E. M. Panov O. M. Khodkevich A. F. Volkov L. K. Vasyanina K. A. Kocheshkov 《Russian Chemical Bulletin》1976,25(7):1493-1498
| 1. | m-Bromo-,-difluoro--chlorostyrene was synthesized and the conditions for the analytical and preparative separation of the cis and trans isomers were determined. They were isolated with a purity of 99.8% as were the isomers of the previously synthesized, - difluoro--chlorostyrene. |
| 2. | The structure of the isomers was confirmed by NMR, NQR, and IR spectroscopies. |
16.
R. R. Shagidullin A. V. Chernova I. A. Nuretdinov G. M. Doroshkina E. V. Bayandina 《Russian Chemical Bulletin》1976,25(1):174-177
| 1. | Absorption bands were observed in the UV spectra of saturated selenophosphoryl compounds that were attributed to the *, n *, and n - * transitions in the selenophosphoryl group. |
| 2. | It was proposed to use the UV spectroscopy method to study the seleno-selenol isomerism in organophosphorus compounds. |
17.
A. A. Onishchenko T. V. Ternikova O. A. Luk'yanov V. A. Tartakovskii 《Russian Chemical Bulletin》1976,25(11):2356-2359
| 1. | Depending on the number and position of alkyl groups, when-,-, and-alkyl derivatives of N-nitropyridinium salts react with nitroalkane salts, they form products of nitration and nitrosation of the nitro-alkane anions, a-nitroalkylation product of N-nitropyridinium, or a mixture of these products. |
| 2. | -Alkyl derivatives of N-nitropyridinium salts with a 2,2-dinitroethane anion form only-dinitroethylation products of N-nitropyridinium. |
18.
| 1. | The corresponding 1,3-bis[-(p-toluenesulfonamido)alkyl]uracils are formed as a result of the reaction of 1, 3-bis(-bromoalkyl)uracils and the Na salt of p-toluenesulfamide. |
| 2. | Interaction of l-(-bromobutyl)uracil with p-toluenesulfamide in a medium of n-butanol leads to formation of 9,18,19,20-tetraoxo-1,6,10,15-tetraazatricyclo[13.3.1.16.10]-eicosa-7, I6-diene,l-(-hydroxybutyl)-2-butoxypyrimid-4-one, and l-(-hydroxybutyl)-2-p-toluenesulfonamidopyrimid-4-one. |
19.
| 1. | The existence of a thermodynamic equilibrium between the trans and gauche conformers in ethyldichlorophosphonate, ethyldichlorothiophosphonate, and ethyldichloroselenophosphonate has been established. |
| 2. | The gauche conformer predominates in compounds I–III at 298°K. In the case of ethyldichlorophosphonate the trans isomer remains in the solid phase, in the thio analog the gauche isomer remains, and in the selenium analog the trans and gauche isomers remain. |
| 3. | The experimentally observed difference in the frequencies of the conformers is close to that calculated under the assumption that their force fields are constant. Nevertheless, the frequencies of the stretching vibrations of the multiple bonds are higher in the trans isomers than in the gauche. |
| 4. | One vibration with predominant participation of the P=X bond ( P=O, P=S, and P=Se) has been isolated in the spectrum of each conformer. The characteristic nature of the vibrations for the bonds just cited decreases along the series indicated. |
20.
| 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. |