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1.
Conclusions The methyl esters of fluorinated -keto acids enter into the Knoevenagel condensation with malonic acid and give fluorinated -hydroxy--carbomethoxy acids, which form copper salts with a ligand:copper composition=1:1. The Cu salts of fluorinated -hydroxy--carbomethoxy acids are photoreduced by alcohols in the presence of UV light to give -hydroxy--carbomethoxy acids and metallic Cu.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1896–1900, August, 1982.  相似文献   

2.
Summary By the reaction of dialkyl esters of -hydroxy, ,-trichloroethylphosphonic acid and acetic anhydride in the presence of a few drops of sulfuric acid, the dialkyl esters of -acetoxy-,,-trichloroethylphosphonic acid were obtained in high yields.  相似文献   

3.
It has been established that the activity of carbon-supported sulfide Ni–Mo, Ni–W and Co–Mo catalysts is much higher compared to the traditional -Al2O3 and SiO2 supported systems. The effect of surface area of the support and of the catalyst composition on their catalytic properties has been studied.
, Ni–Mo, Ni–W Co–Mo , . .
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4.
Carbolines     
4-Substituted 3, 4-dihydro--carbolines (X–XVI) were obtained by the Beckman rearrangement of oximes of -(indolyl-3)ketones (I–IV, IX) under the action of phosphorus pentachloride in nitrobenzene. 3, 4-Dihydro--carbolines were converted into -carbolines (XV–XVII) on heating with Brown's palladium catalyst in ethylene glycol. Oximes containing the aryl group react on treatment with p-toluene sulfochloride in pyridine with the formation of the arilides of -(indolyl-3)propionic acids.For preliminary report, see [18].  相似文献   

5.
Form ose reaction, the Ca(OH)2 catalyzed condensation of HCHO to a complex mixture of sugars, does not lose its autocatalytic nature at 98°C. The induction period is 15 sec, and then, at 18% total HCHO conversion, there was a period of approximately 3 sec duration in which the reaction had produced C6 sugars at 84.3 wt.% selectivity. Glucose amounted to 90% of those sugars, and no branched sugars were detected. Conversion was complete within 3 min. The simple nature of the product was lost at lower temperatures or higher conversions.
— HCHO, Ca(OH)2, 98°C. 15 , 38%- HCHO 3 , C6 84,3 . %. 90%, . 3- . .
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6.
The results of investigations on intercalated crystalline zirconium phosphate are described in the literature. The behaviour of crystalline phosphates containing both zirconium and titanium metal ions has not been investigated previously. Within these investigations, the thermal behaviour of such materials has been studied in the temperature interval 25–1000 °C by simultaneous recording of TG, DTG and DTA curves. The results are presented in this paper.
Zusammenfassung Ergebnisse über Untersuchungen an in Schichten eingelagerten kristallinen Zirkoniumphosphat sind in der Literatur beschrieben. Das Verhalten kristalliner Phosphate, die sowohl Zirkoniumals auch Titanmetallionen enthalten, wurde bis jetzt nicht untersucht. Als Teil dieser Untersuchungen wurde das thermische Verhalten solcher Materialien im Temperaturbereich 25–1000 °C durch simultanes Registrieren der TG-, DTG- und DTA-Kurven näher bestimmt, dessen Ergebnisse hier dargelegt werden.

. , . , , 25–1000°. .
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7.
The direct nitration and acetylation of 1-methyl-, 1-ethyl-, and 1-benzyl-2-[-(2-furyl)vinyl]benzimidazoles has given the corresponding 1-alkyl- and 1-benzyl-2-[-(5-nitro-2-furyl)vinyl]benzimidazoles and 1-alkyl- and 1-benzyl-2-[-(5-acetyl-2-furyl)vinyl]benzimidazoles. The UV spectra of these compounds have been recorded and their ionization constants have been determined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 6, pp. 832–834, June, 1970.  相似文献   

8.
    
The previously unreported N, N-diformyl-, -bipiperidyl has been synthesized by the reaction of ,-bipiperidyl with carbon monoxide under pressure.  相似文献   

9.
Fragments of the zeolite structure have been calculated by the EHT method. The results are in agreement with spectral data on structural hydroxy groups of zeolites.
PMX . .
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10.
The characteristics of crystallization, melting and spherulitic growth of a random propylene copolymer (PRC) containing small amount of ethylene were studied in the presence of a selective -nucleating agent (calcium pimelate). It was established that the products of isothermal and non-isothermal crystallization are very rich in -modification but have mixed polymorphic composition. The formation of -modification may be attributed to -transition on the surface of growing -spherulites resulting in -twin-spherulites. During melting of PRC of -modification, the characteristics observed with -nucleated propylene homopolymers, namely, a -recrystallization of recooled samples and separated melting of non-recooled samples (i.e. the melting memory effect), as well as a -recrystallization leading to a perfection of the structure within the -modification, are also demonstrated. The disturbance of regularity of the polymer chain highly reduces the tendency to -crystallization. In contrast to the observations with propylene homopolymers, the growth rate of -modification (G ) is higher than that of -modification (G ) and no critical crossover temperature can be found (T()=413 K) below whichG >G . The experimental results show that a partial disturbance of chain regularity by incorporation of comonomer units considerably reduces the tendency to -crystallization.This research was supported by the National Scientific Research Fund (OTKA), the author is grateful for it. Thanks are due to Professor Géza Bodor for his help in X-ray diffractometric investigations and to Ms. Tünde Lócska for her prudential technical assistance in the optical experiments.  相似文献   

11.
It has been shown that pyrazoles (hydroxypyrazoles) are formed upon reaction of fluorine-containing copper -diketonates (-ketoesterates) with hydrazines and their hydrochlorides. A preparative method has been developed for the synthesis of fluorinated pyrazoles and hydroxypyrazoles via treatment of fluorine-containing -diketonate and -ketoesterate copper compounds with hydrazines. The molecular structure of 1-phenyl-3-octafluorobutyl-5-hydroxypyrazole has been established based on x-ray structural analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 640–645, March, 1990.  相似文献   

12.
Conclusions Homologs of p-phenoxystyrene that had not been described in the literature have been synthesized: -methyl-p-phenoxystyrene, -ethyl-p-phenoxystyrene, ,-dimethyl-p-phenoxystyrene, -methyl-p-phenoxystyrene, and ,-dimethyl-p-phenoxy styrene.  相似文献   

13.
We have determined the spectroscopic characteristics, the dipole moments, and the Kerr constants of the stereoisomers of the secondary-tertiary diols of the cyclohexane and bicyclo [4.1.0]pentane series: 3,4-dihydroxy-3-carane (I), 3,4-dihydroxy-3-methylnorcarane (II), 3,4-dihydroxy-3-methylnorcarane (III), 4, 5-dihydroxy-3-methylcyclohexene (IV), 3,4-dihydroxy-3-carane (V), 3,4-dihydroxy-3-methylnorcarane (VI), 3, 4-dihydroxy-3-carane (VII), and 3,4-dihydroxy-4-methyl-3-carane (VIII). It was found that the cis diols are more polar than their trans isomers. It was shown by electrical and electrooptical methods that rotamers with a gauche orientation with respect to the tertiary C-O are stable relative to those containing the diol at the ordinary C-C bond of the ring.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 619–625, March, 1991.  相似文献   

14.
A new and more effective sequence of reactions is proposed for the production of 16,17-isopropylidenedioxy-5-pregnane-3,21-diol-20-one. It uses methods previously unused for 5-H-steroids and involves 21-hydroxylation of 16,17-epoxy-5-pregnan-3-ol-20-one with diacetoxyiodobenzene and cis-opening of the obtained 21-hydroxy-16,17-epoxy-5-pregnane-3,21-diol-20-one by acetic acid in the presence of epoxycarbonylhydrazine, followed by condensation of the obtained product with acetone.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1185–1188, May, 1991.  相似文献   

15.
The reaction of -arylacrylyloxiranes with phenyl azide by refluxing in dioxane or toluene leads to -phenylamino--aryl-acrylyloxiranes. Epoxypropionyl- and -hydroxypropionyltriazoles are also isolated when the reaction is carried out in the dark without heating. It is shown that -phenylamino--arylacrylyloxiranes undergo cyclization to 3(2H)-furanones in an acidic medium, whereas they are converted to 2,3-dihydro-4-pyridones under basic-catalysis conditions.Translated from Khimiya Geterotsiklicheskikh Soedineii, No. 8, pp. 1022–1027, August, 1988.  相似文献   

16.
The cyclization of 1,1-dichloro-5-(2,5-dimethoxyphenyl)-1,3-pentadien-5-one and the product of its partial demethylation leading to the corresponding derivatives of 2-pyrone and 2-(,-dichlorovinyl)-6-methoxy-4-chromanone has been studied. Irradiation causes the dimerization of 1,1-dichloro-5-(2,5-dimethoxyphenyl)-1,3-pentadien-5-one.For part I, see [1].  相似文献   

17.
On the basis of matrices of transfer of atoms kinetic equations of isotope transfer between the components participating in elementary reactions have been derived.
, .
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18.
It was found by cyclic voltammetry and ESR that the excitation of the molecules of , derivatives of -(5-nitro-2-furyl)--cyanoethylene in the radical-anion state by one-electron electrochemical reduction promotes chemical transformation of the other reaction centers, while preserving the nitrofuran group.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1636–1639, December, 1991.  相似文献   

19.
The thermal properties of -lactoglobulin (-LG) were studied by differential scanning calorimetry (DSC) under different medium conditions.pH, neutral salts, protein perturbants, and polyols all affected the DSC characteristics of -LG. Acylation with fatty acids also changed the thermal properties, particularly peak width at half-height. The results suggest that the structural stability of -LG is controlled by non-covalent forces, particularly electrostatic and hydrophobic interactions. Disulfide bonds did not contribute to the thermal response of -LG. Fatty N-acyl-amino acids caused marked increases in thermal stability and decreases in denaturation enthalpy, and additional peaks were observed in the presence of some palmitoyl derivatives.Contribution No. 2310, Centre for Food and Animal Research.We thank D. Raymond for her excellent technical assistance.  相似文献   

20.
Ethyl esters of -(3-chloro-1,4-naphthoquinon-3-yl)crotonic or cinnamic acids were obtained by the reaction of 2,3-dichloro-1,4-naphthoquinone with ethyl esters of N-substituted -aminocrotonic or -aminocinnamic acids. These esters were converted by alkaline fusion into benz[f]indole-4,9-dione-3-carboxylic acids, and into ethyl esters of benz[g]indole-4,5-dione-3-carboxylic acid by the action of acetic acid.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 66–68, January, 1989.  相似文献   

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