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Information × Registration Number 0216U001343, 0115U003539 , R & D reports Title Design of surfactant-based supramolecular aggregates for catalysis and molecular recognition popup.stage_title Head Anatolii F. Popov, Доктор хімічних наук Registration Date 08-02-2016 Organization The L.M.Litvinenko Institute of Physical-Organic Chemistry and Coal Chemistry popup.description2 Objects of the study: supramolecular aggregates based surfactant, a nucleophilic substitution reaction and oxidation in organized molecular systems, inorganic and organic а-nucleophiles. Objective: Based on the analysis of various factors to identify ways to control the effects of micellar catalysis in nucleophilic substitution reactions and oxidation in ensembles of pairs of different types. Methods: UV spectroscopy; potentiometry; conductometry; tensiometry; by IR, 1H NMR, 13C NMR; general preparative methods and synthetic chemistry. The reactions of the alkaline hydrolysis of 4-nitrophenyl dietilfosfonovoy (NFDEFS) diethylphosphoric (NFDEF) and 4-toluenesulphonic (NFTS) acid in the presence of micelles of monomeric and dimeric cationic surfactants. Whatever the structure of the surfactant in the transfer reaction in micelles nucleophilicity hydroxide ion is reduced 2-4 times as compared with water and is 0.06 - 0.03 (NFDEFS) 0.0025 - 0.0035 (NFDEF) and 0.002 - 0.003 (NFTS), l / (mol . s). Effects of concentration of reactants in the micelles thus in all cases to compensate decrease so as to increase the nucleophilicity of the observed reaction rates of 4-20 times (depending on the system). Nature center cationic surfactants (tetraalkilamonievy, imidazolium) does not substantially affect the reactivity of the hydroxide ion. If we compare the effects of micellar surfactant dimeric and monomeric, the use of the latter allows for high reaction rates due to more efficient binding of the substrate and the reagent. Studied the reactivity of stable peroksisolvatov (gidroperit and Persol) in the oxidation metilfenilsulfida (ISF) in the presence of ammonium monocarbonate in water, an aqueous iso-propanol, CTAB micelles and cationic microemulsion. It is established that under the experimental conditions gidroperit reacts with hydrogen peroxide to identical velocities (in solution). This fact allows us to recommend gidroperit as an effective environmentally friendly oxidant for applications in the design of oxidative degassing systems. Displaying Percy not require additional activation carbonates, and is an effective oxidizing agent, is suitable for long-term storage and safe. Defined that CTAB micelles second order rate constant for the oxidation MFS peroksimonokarbonat anion generated from both the hydrogen peroxide and peroksidsolvata with an order of magnitude higher than similar rate constants corresponding noncatalytic processes. In alkaline environments, systems based organocomplexes dibrombromat anion (generated by dissolving in water nucleophilically-oxidant pairs HOBr / BrO-), in the presence of micelles of cationic surfactant increase the reaction rate constants observed cleavage NFEF, NFDEFS and NFTS is ~ 15-90 times. The surfactant micelles, as in water, the anion is BrO- а-nucleophile, and а-out effect in the transfer reaction of the water micelles practically unchanged. Micellar effects depend on the nucleophilicity PAR hypobromite ion into detergent micelles, the efficiency of solubilization of the substrate and the anion BrO-, which significantly affect the concentration of counter ions in the surface layer of the micelles. This determining factor is the observed acceleration of the concentration of the reagents in micellar pseudophase. Kinetic of reactions nemitselloobrazuyuschih oxime (monoizonitrozoatseton, MENA, butane-2,3-dione monooksim; BDMO) with carboxylic esters (p-nitrophenyl acetate, n-nitrofenilbenzoat), phosphorus (bis (2, 4-dinitrophenyl) phosphate) and sulfone (NFTS) dimer acids in micelles of surfactants. Dependence of the observed rate constants of reactions of pseudo the order of the surfactant concentration for the systems studied are typical bimolecular reactions are well described and psevdofaznoy distribution model. Analysis of the results showed that MENA exhibits greater nucleophilicity in spallation ester bonds than BDMO. Product Description popup.authors Аніщенко В.М. Бєлоусова І.О. Бураков М.І. Дикун О.М. Дріжд В.Л. Калафат К.В. Капітанов І.В. Карпічев Є.А. Мітченко О.С. Сердюк Г.О. Фролова І.Б. Чотій К.Ю. Шологон В.І. Шумейко О.Є. popup.nrat_date 2020-04-02 Close