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1.
| 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. |
2.
A research project is described, which is being carried out systematically with the objective of qualitative and quantitative assessment of organic substances occurring in the air at forest sites considering seasonal and meteorological variations. To begin with, a collecting and analytical system with diverse additional modules had to be developed and assembled for this purpose. With the aid of an adsorptive enrichment system this enables the determination of the entire palette of organic substances present in the air at the site.Hitherto, about 160 of the major organic substances occurring in the air at the site have been determined. These occur at concentrations between several ng to several g per m3 air and belong to different classes of compounds. So-called reference substances have been selected as representatives of particular classes of substances. The alterations of concentrations in air at the site of these reference substances have been investigated as a function of meteorological conditions. The evaluation of the data led to the following conclusions:
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| – | The influence of wind direction, i.e. the long-distance transport of emission, is particularly significant with respect to presence and concentration of organic substances in air at the site. |
| – | The humidity prevailing during sampling at the site has a significant influence on the concentration of airborne organic compounds of natural origin, e. g. acetophenone. |
| – | There are indications that the wind velocity also plays a significant role on the concentration of organic substances in air at the site during uniform wind direction. |
3.
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. |
4.
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. |
5.
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. |
6.
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. |
7.
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. |
8.
A. A. Onishchenko O. S. Reshetova V. P. Gorelik O. A. Luk'yanov V. A. Tartakovskii 《Russian Chemical Bulletin》1976,25(5):1135-1137
| 1. | n-Nitro-p-toluenesulfonic acid N-nitroamide adds to olefin oxides to give N--hydroxyalkylation products. The direction of the addition to monosubstituted oxides is such that the nitroamide anion adds to the most sterically available carbon atom. |
| 2. | m-Nitro-p-toluenesulfonic acid N-nitroamide reacts with unsubstituted ethylenimine to give the ethylenimine salt of the nitrosulfonamide. |
| 3. | m-Nitro-p-toluenesulfonic acid N-nitroamide reacts with an N-acylated ethylenimine or trimethylenimine with ring opening and the respective formation of N-- or N--amidoalkylation products. |
9.
E. F. Panarin V. V. Kopeikin V. M. Denisov A. I. Kol'tsov 《Russian Chemical Bulletin》1976,25(3):532-535
| 1. | Carbon-chain polymers with -diketone and -keto ester functional groups in the side chains have been synthesized. |
| 2. | The tautomeric equilibrium of the polymeric -dicarbonyl compounds polymethacryloylacetone and poly(vinyl acetoacetate) and low-molecular models of these polymers has been studied. The effect of the macromolecular nature of the polymeric -diketones on the tautomeric equilibrium is expressed as a significant difference between their thermodynamic equilibrium parameters and those of the low-molecular analog. |
10.
O. A. Luk'yanov Yu. B. Salamonov S. I. Zherebyat'ev Yu. A. Strelenko 《Russian Chemical Bulletin》1989,38(5):1006-1011
| 1. | Regioselective methods are proposed for synthesis of N-(-hydroxyalkyl)diazene-N-oxides by reaction of nitroso compounds with N-(-hydroxyalkyl)hydroxylamines or with N,N-dichloro-2-hydroxyalkylamines. |
| 2. | The possibility was shown of obtaining N--oxo- and -arylaminocarboxyl derivatives of diazene-N-oxides by treatment of N-(-hydroxyalkyl)diazene-N-oxides with aluminum isopropylate and phenyl isocyanate respectively. |
11.
| 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. |
12.
| 1. | It was shown on the example of the reaction of 1-hydroxy-5-methyltetrazole with methyl vinyl ketone that N-hydroxytetrazoles attach to substances with activated multiple bonds. The addition products are solely the products of N(3 and 4)--oxoalkylation. |
| 2. | Upon heating, 3- and 4--oxoalkylated 1-oxides of tetrazoles are in a tautomeric equilibrium. |
13.
E. S. Klimchuk I. V. Khudyakov L. A. Margulis V. A. Kuz'min 《Russian Chemical Bulletin》1988,37(12):2462-2467
| 1. | The application of an external magnetic field (H=0.18 T) leads to an increase of 10–150% in the escape of the radicals of xanthene dyes from the cage in a viscous solvent. |
| 2. | In erythrosine and ethyleosin, which contain heavy atoms, the magnetic effects (with /T=3.3 cP/K) are smaller than in the case of fluorescein. This is due to the appearance of spin-orbital interaction in the radicals of the pair; the internal heavy atom effect appears in viscous media (/T cP/K). |
| 3. | The presence of an external heavy atom leads to a decrease of the magnetic effect during the photoreduction of fluorescein and erythrosine. The external heavy atom effect appears in the region of moderate fluidities (1 /T 7 cP/K, [KI]=0.1 M). This effect does not appear with large /T values on account of the transition to the diffusion-controlled region. |
14.
A. M. Turuta A. V. Kamernitskii A. A. Korobov V. S. Bogdanov 《Russian Chemical Bulletin》1988,37(11):2352-2356
| 1. | The reaction of 16-methylpregna-5,16-dien-3-ol-20-one with iodobenzene diacetate in a methanolic alkali solution proceeds with a Favorskii rearrangement, with formation of 16-methylpregna-5, 16-dien-3-ol-21-ic acid and its methyl ester. |
| 2. | A new method for the synthesis of 21-hydroxy-16,17-epoxy-20-ketosteroids from 16-methyl-16,17-epoxypregn-5-en- 3-ol-20-one has been proposed. |
15.
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. |
16.
| 1. | We accomplished the stereospecific cis-opening of the aziridine ring of 16,17-epiminopregn-5-en-3-ol-20-one by treatment with thiocyanic acid in the presence of a reagent on the carbonyl group, which was accompanied by cyclization with the formation of 2-aminopregn-5-en-3-ol-20-one[16,17-d]thiazoline. |
| 2. | Employing IR and UV spectroscopy, a study was made of the structure and tautomeric equilibrium of the 2aminothiazolines and their N-acetylated derivatives; all of the obtained compounds represent a mixture of tautomers. |
17.
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. |
18.
| 1. | A practicable method for the synthesis of vicinal bis(difluoramino)-containing carboxylic acids by reacting tetrafluorohydrazine with unsaturated acids has been developed. |
| 2. | ,-Bis(difluoramino)carboxylic acids are unstable and undergo decarboxylation followed by dehydrofluorination. |
| 3. | ,-Bis(difluoramino)carboxylic acids are fairly stable and in some cases display the properties of ordinary carboxylic acids. |
19.
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. |
20.
A. P. Brestkin I. L. Brik L. I. Ginetsinskaya N. N. Godovikov M. I. Kabachnik E. G. Kireeva S. A. Trifonova 《Russian Chemical Bulletin》1976,25(4):861-864
| 1. | O,O-Diisopropyl-, O,O-dipropyl, and O,O-dibutyl-S-(-N, N-cyclohexy]methylaminoethyl)thiophosphates and their methiodides were synthesized and their anticholinesterase activity was determined in relation to butyrylcholinesterase from horse blood serum and acetylcholinesterase from human erythrocytes. |
| 2. | O,O-Diisopropyl-S-(-N, N-cyclohexylmethylammoethyl)thiophosphate and its methiodide display the largest effect of selective effect in relation to butyrylcholinesterase. |