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61.
Summary When reaction is initiated with t-butyl peroxide, carboxylic acids add to one double bond of dialkyldially lsilanes with subsequent homolytic intramolecular cyclization of the intermediately formed free radical with formation of a compound containing a silicon atom in a six-membered ring. 相似文献
62.
Reaction thermodesorption is studied. A generalized wiew is offered regarding the routes along which the transformations take place under the conditions of temperature-programmed desorption.
. , .相似文献
63.
Petrov P Stassin F Pagnoulle C Jérôme R 《Chemical communications (Cambridge, England)》2003,(23):2904-2905
Multi-walled carbon nanotubes (MWNTs) have been solubilized in water and in various organic solvents by noncovalent side-wall functionalization by pyrene containing polymers. 相似文献
64.
Petar J. Petrov Alexi A. Alexiev Galin Petrov Gianluca Giorgi 《Journal of heterocyclic chemistry》2005,42(2):313-317
The coumarino‐[3,4‐c]‐3H‐10‐methyl‐2‐oxo‐2‐phenyl‐1,2‐oxaphosphole was prepared by the addition of PhPCl2 to 3‐acetylcoumarin in the presence of acetic anhydride. Its conversion to the isomeric coumarino‐[3,4‐c]‐9H‐9‐methyl‐2‐oxo‐2‐phenyl‐1,2‐oxaphosphole was studied in different reaction conditions. The structures of the two isomers were determined by X‐ray crystallography and by ab initio molecular orbital calculations. 相似文献
65.
V. I. Zhukov G. V. Val’kovich B. N. Skorik Yu. M. Petrov G. P. Belov 《Russian Journal of Applied Chemistry》2007,80(7):1195-1200
Analysis of mass and heat balance in the reaction node of the process of ethylene dimerization into but-1-ene under the industrial
conditions is performed. It is found that ethylene concentration in the reactor liquid phase by a complex way depends on the
reactor temperature, pressure and but-1-ene concentration in the liquid phase. Optimal process temperature is 80–90°C, operating
pressure in the reactor is 0.6–0.8 MPa. Increase in pressure above 1 MPa practically excludes heat withdraw via but-1-ene
evaporation and makes the system of heat withdrawing ineffective. 相似文献
66.
Metalation of diethylphosphono-acetone (DÄPA) with potassium or lithium in benzene and with KNH2, LiNH2, or calcium in liquid ammonia afforded the metal derivatives ofDEPA, which were isolated in a pure state. Their structure has been investigated by i.r.- and1H n.m.r.-spectroscopy. In solution metallotropic conversion of thecis-enolate chelates intotrans-enolates and C-forms occurs. The reactivity of these metal derivatives towards some alkylating and acylating reagents as well towards carbonyl compounds has been investigated.
Mit 1 Abbildung
Diese Mitteilung ist z. T. Inhalt der Diplomarbeit vonI. Velinov, Univ. Sofia (1968). 相似文献
Mit 1 Abbildung
Diese Mitteilung ist z. T. Inhalt der Diplomarbeit vonI. Velinov, Univ. Sofia (1968). 相似文献
67.
V. P. Kazakov S. V. Lotnik V. N. Korobeinikova V. M. Kalinina L. A. Khamidullina R. G. Bulgakov A. N. Petrov 《Russian Chemical Bulletin》1991,40(8):1720-1720
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, p. 1934, August, 1991. 相似文献
68.
A. A. Shcherbakov I. P. Danilov V. A. Sazhin V. I. Petrov 《Theoretical and Experimental Chemistry》1993,28(4):277-279
An investigation of the hydration and amphiphilic properties of the piracetam and pramiracetam molecules has been conducted by theoretical conformational analysis and the Monte Carlo method; their localization and orientation at the water-lipophilic medium interface have been determined, which made it possible to explain the characteristics of the pharmacological action of the drugs.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 28, No. 4, pp. 355–358, July–August, 1992. 相似文献
69.
At 20–70 °C, the temperature has almost no effect on the semisaturation field,B
1/2, or on the magnetic effects detected by exciplex fluorescence (pyrene/N,N-dimethylaniline) in binary benzene-DMSO mixtures. In individual solvents (ethanol, methanol) heating leads to a noticeable
increase in the magnetic effect, whileB
1/2 decreases. The results obtained corroborate a previously proposed hypothesis that polar microclusters are formed in binary
solvents with components of different polarity.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1821–1823, October, 1993. 相似文献
70.
Appropriately protected guanosine derivatives were successfully converted to the corresponding O6-substituted guanosine derivatives by treatment with dialkyl- or diaryl-phosphoryl halides, dialkyl- or diaryl-phosphinothioyl halides, arenesulfonyl chlorides, and trialkylsilyl chlorides. 相似文献