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1.
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   

2.
    
The previously unreported N, N-diformyl-, -bipiperidyl has been synthesized by the reaction of ,-bipiperidyl with carbon monoxide under pressure.  相似文献   

3.
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   

4.
Conclusions The chlorination of 3-carene by N-chlorosuccinimide gave (–)-4-chloro-3 (10)-carene, (–)-3,4-dichlorocarane, (+)-3,4-dichlorocarane, and 2,8-dichloro-p-mentha-1(7),5-diene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 206–209, January, 1987.  相似文献   

5.
Reaction of -arylacryloyloxiranes with hydrazine hydrate takes place via intermediate ,-epoxyalkylpyrazoles which then undergo intramolecular oxidative-reductive disproportionation to yield -hydroxyalkylpyrazoles.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 633–636, May, 1990.  相似文献   

6.
The energy level separation in symmetrical and unsymmetrical double minimum potentials in the presence of electric fields is calculated by first-order perturbation theory, from which the tunnelling probability of protons is obtained for both perturbed and unperturbed potentials. Tunnelling probability is slightly increased by fields of about 105 V/m, but a greater increase in tunnelling probability occurs when a symmetric potential becomes unsymmetric. The tunnelling process is too rapid to account for observed differences in dehydroxylation behaviour of Al(OH)3, Mg(OH)2 and kaolinite under electrolysis. Estimates, from indirect evidence, of the rates of anion defect generation and annihilation support the theory that the rate-determining field-dependent process is the surmounting of anionic lattice vacancies by oxygen-containing species.
Zusammenfassung Die Trennung des Energieniveaus in symmetrischen und unsymmetrischen doppelten Minimumpotentialen in Gegenwart von elektrischen Feldern wird mittels einer Störungstheorie erster Ordnung berechnet, aus welcher die Wahrscheinlichkeit der Tunnelbildung von Protonen für gestörte sowie ungestörte Potentiale erhalten wird. Felder von 105V/m erhöhen die Wahrscheinlichkeit der Tunnelbildung in geringem Maße, eine bedeutendere Zunahme der Wahrscheinlichkeit der Tunnelbildung tritt jedoch auf, wenn ein symmetrisches Potential unsymmetrisch wird. Der Vorgang der Tunnelbildung ist zu schnell um die Unterschiede des Verhaltens von Al(OH)3, Mg(OH)2 und Kaolinit bei der elektrolytischen Dehydroxylierung zu erklären. Schätzungen der Geschwindigkeiten der Anionen-Defektbildung und -Vernichtung aus indirekten Angaben unterstützen die Theorie, daß der geschwindigkeitsbestimmende, feldbedingte Vorgang die Überdeckung der Lücken im Anionengitter durch sauerstoffhaltige Arten ist.

Résumé La séparation des niveaux d'énergie des potentiels à minimum double, symétrique et asymétrique, se calcule à l'aide de la théorie des perturbations du premier ordre, à partir de quoi la probabilité de l'effet tunnel des protons s'obtient aussi bien pour les potentiels perturbés que pour les non perturbés. La probabilité de l'effet tunnel augmente quelque peu sous l'influence de champs d'environ 105 V/m, mais une augmentation plus notable de cette probabilité apparaît quand un potentiel symétrique devient asymétrique. Le processus de l'effet tunnel est trop rapide pour rendre compte des différences de comportement observées pour Al(OH)3, Mg(OH)2 et la kaolinite lors de l'électrolyse déshydroxylante. Des estimations faites à partir de données indirectes pour connaître les vitesses d'apparition des défauts anioniques et celles de leur disparition, viennent à l'appui de la théorie suivant laquelle le processus dépendant du champ et déterminant la vitesse est celui de l'occultation des lacunes du réseau anionique par des espèces contenant de l'oxygène.

. , . 105V/; , . , Al(OH)3, Mg(OH)2 . , , .


Part of this work was carried out under an S.R.C. research grant. The author is indebted to Dr. J.P.M. Bailey for advice on the quantum-mechanical calculations, Dr. W.T. Raines and Dr. P.G. Rouxhet for helpful discussion. and to Mrs. F. Jackson for the computing.  相似文献   

7.
The use of a dicobalt hexacarbonyl protective group permitted us to carry out the stereospecific conversion of 17-hydroxy-17-ethynylsteroids into branched 17-R-substituted 17-ethynylsteroids (R-OH, OAc, OMe, NCS, and F).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 675–681, March, 1990.  相似文献   

8.
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   

9.
The electron-impact mass spectra of the E- and Z-isomers of the ,-methyl substituted esters of -phenyloxiranecarboxylic acids have been studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1310–1314, October, 1986.  相似文献   

10.
A new criterion for evaluating different plasticizers the ability of suppression of the transition in plasticized PVC blends. Accordingly, the suppression ability is proportional to the PVC-plasticizer compatibility, expressed either by the critical solution temperature, CST, or by the interaction parameter related to the difference between the solubility parameters of the blend components. The criterion is, however, valid for low plasticizer contents (<5%w/w) only, as long as the transitions are not overlapped by the transitions, shifted towards lower temperatures due to the effect of the plasticizer. For higher plasticizer contents the transition starts to overlap the transition and the suppression ability of the plasticizer depends increasingly on the efficiency of the plasticizer i.e. on the depression of the glass transition temperature of PVC (related to theT g of the plasticizer). Accordingly, plasticizers with both good efficiency (lowT g) and compatibility are more effective in the suppression than plasticizers which have only a higher compatibility but also a highT g (i.e. reduced efficiency).One of the authors, Tiberiu Vilics, thanks the Konferenz der Deutschen Akademien der Wissenschaften; and Volkswagen Stiftung; for financial support for a research fellowship at the Institut für Makromolekulare Chemie, Freiburg. The financial support of the Deutsche Forschungsgemeinschaft (SFB 60) is greatfully acknowledged.  相似文献   

11.
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   

12.
The catalytic hydrogenation of N--cyanoacylureas and 1-alkyl-3--cyanoacylureas in the presence of hydrochlorides of aromatic amines has given N--arylaminoacryloyl-, 1-alkyl-3--arylaminoacryloyl-, N--alkyl--arylaminoacryloyl-, and 1-alkyl-3--alkyl--arylaminoacryloylureas. The action of N- -phenylaminoacryloyl- and 1-methyl -3- -phenylaminoacryloylureas of ethanolic hydrogen chloride has given uracil and 1-methyluracil.For Communication IX, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 6, pp. 847–850, June, 1970.  相似文献   

13.
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   

14.
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   

15.
The available data (supplemented where necessary) on the electronic, nuclear magnetic resonance and vibrational spectra of metal -ketoenolates has been analysed to assess the relative contributions of donor and acceptor metal-ligand -bonding in the first transition period metal (III) -ketoenolates. The effects of the metal ion and the ligand substituent on the -interaction in the -ketoenolate ring are discussed in terms of established theoretical concepts.
Zusammenfassung Die bekannten Daten (ergÄnzt, falls notwendig) der elektronischen und kernmagnetischen Resonanz sowie der Schwingungsspektren von Metall--ketoenolaten wurden analysiert, um die relativen BeitrÄge von Donor- und Akzeptor (Metall-Ligand) -Bindung in Metall(III)ketoenoIaten der ersten übergangsperiode zu ermitteln. Die Einwirkung des Metallions und des Ligandsubstituenten auf die -Bindung im -Ketoenolatring werden diskutiert auf der Grundlage von bekannten theoretischen Prinzipien.

Résumé L'examen des résultats antérieurement publiés (supplementés ou nécessaire) des spectres électroniques, résonance nucléaire magnétiques et vibrationnel nous a amenés à préciser les contributions relatifs de liaison- donneur et accepteur entre métal et ligand de la première période transitionelle métal(III) -kétoénolates. Les effects de l'ion métallique et du ligand substituent exercés sur l'interaction- dans le noyau -kétoénolate sont discutés selon les idées théoriques déjà établies.


This work was supported by University of Cape Town and C.S.I.R. Research Grants. We thank the National Institute for Metallurgy for a bursary (to R.D.H.).  相似文献   

16.
The glycosylation reaction of 6-nitroindoline with 5-tritylribose led to the synthesis of the 1--D-ribofuranoside and 1--D-ribopyranoside of 6-nitroindoline, the dehydrogenation of which resulted in the isolation of the corresponding 1--D-ribopyranoside and 1--D-ribofuranoside of 6-nitroindole; the last with protecting groups are suitable for utilization in oligonucleotide synthesis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1500–1506, November, 1990.  相似文献   

17.
Individual 2-aryl- and 2,4-diaryl-cis-thiadecalin-1-oxides and 1,1-dioxides have been synthesized. The effect of sulfinyl and sulfonyl groups has been observed on the chemical shifts of carbon atoms in these conformationally homogeneous, stereochemically similar systems.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 463–467, April, 1987.  相似文献   

18.
Reaction of bromoacetone with the accessible methyl--nitropyridines has given some 6- and 8-nitroindolizines. In the case of ,'-dimethyl--nitropyridines, both the 8- and 6-nitroindolizines were obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 203–208, February, 1987.  相似文献   

19.
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   

20.
The synthesis of two-ring 1,4-thiazine systems was previously accomplished on the basis of the reaction of o-amino mercapto derivatives of pyridine and pyrimidine with dicarbonyl compounds — halo -keto esters and halo -diketones. In the present paper it is shown that the primary products of this reaction are S--keto-alkylmercapto derivatives, which are subsequently cyclized to the corresponding hydroxy amino compounds. The latter are converted to N-acylamino-S--carbethoxy (keto)alkylmercapto derivatives under the influence of an alkaline agent. The indicated compounds were isolated and characterized [2, 3].See [1] for communication 36.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 250–253, February, 1979.  相似文献   

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