Free-radical addition of aliphatic carboxylic acids to dialkyldiallylsilanes

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.     

A study of the surface heterogeneity and catalytic activity of catalysts by means of reaction thermodesorption

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.

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Noncovalent functionalization of multi-walled carbon nanotubes by pyrene containing polymers

Multi-walled carbon nanotubes (MWNTs) have been solubilized in water and in various organic solvents by noncovalent side-wall functionalization by pyrene containing polymers.     

Synthesis and structural characterization of isomeric coumarino‐1,2‐oxaphosphole derivatives

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.     

Selective dimerization of ethylene to but-1-ene under the conditions of industrial process. I. Influence of temperature and pressure on the rate of the process in a bubbling type reactor

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.     

Darstellung,Struktur und Reaktionsfähigkeit einiger Metall(I)- und-(II)-Derivate des Diäthylphosphono-Acetons

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.

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Diese Mitteilung ist z. T. Inhalt der Diplomarbeit vonI. Velinov, Univ. Sofia (1968).     

Radiothermoluminescence of polycrystalline high-temperature superconducting YBa2Cu3O6.94, EuBa2Cu3O6.9, and SmBa2Cu3O6.9 samples

Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, p. 1934, August, 1991.     

Investigation of the effects of hydration and amphiphilic properties of nootropic drugs of piracetam and pramiracetam

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.     

Fabrication of "hairy" colloidosomes with shells of polymeric microrods

Novel colloidosome microcapsules with aqueous gel cores and integral shells of rodlike polymeric particles have been prepared and characterized. The synthesis is based on templating water-in-oil emulsions stabilized by rodlike particles followed by gelling of the aqueous phase, dissolution of the oil phase in ethanol, and redispersion of the obtained colloidosome capsules in water. Such capsules may find applications as vehicles for delivery and controlled release of drugs, cosmetics, and food supplements.