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21.
Russian Journal of Organic Chemistry - Aminomethylation of calix[4]resorcinarenes with (1-hydroxyethane-1,1-diyl)bisphosphonic acid afforded a series of new water soluble onium salts.  相似文献   
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The aggregation in poly(ethylene imine) (poly(ethylene glycol))-calix[4]resorcinarene-water-dimethylformamide (30 vol %) systems and the catalytic activity of these compositions in hydrolysis of 4-nitrophenylbis(chloromethyl)phosphinate are studied by conductometry, tensiometry, lightscattering, and viscometry. Critical association concentrations, hydrodynamic radii of polymer-colloid aggregates, and kinetic parameters of hydrolysis are determined.  相似文献   
23.
Herein we report our studies on the acid-catalyzed cyclisation of N-(4,4-diethoxybutyl)sulfonamides at the presence of polyatomic phenols as an efficient one-pot approach to the synthesis of 1-sulfonyl-2-arylpyrrolidines from the acyclic precursors.  相似文献   
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The methods of cyclic voltammetry, electrolysis, and spectrophotometry were used to study electrochemical properties of (TCAS + Fe3+ + dipy), (CCAS + Fe3+ + dipy), and (CCAS + Fe3+ + [Co(dipy)3]3+) triple systems (where TCAS is n-sulfonatothiacalix[4]arene, CCAS is tetracarboxylate n-sulfonatocalix[4]arene, and dipy = α,α′-dipyridyl) in an aqueous solution. One-electron reduction of Fe(III) in the (TCAS + Fe3+ + dipy) system at pH 2.5 results in electroswitching of iron ions from the lower TCAS ring to the upper ([Fe(dipy)3]2+). Reverse electrochemical switching of the system is impossible due to mediator ([Fe(dipy)3]2+/3+) oxidation of TCAS. Reverse electroswitching of Fe(III) ions from unbound to bound state as ([Fe(dipy)3]2+) with CCAS has been revealed in the system (CCAS + Fe3+ + dipy) (pH 1.7) upon single-electron transfer, whereas reversible electroswitching by the upper rim of CCAS from one complex ion ([Co(dipy)3]3+) to another ([Fe(dipy)3]2+) has been demonstrated in the system ([Co(dipy)3]3+ + CCAS + Fe3+ upon double-electron transfer. In all systems, electric switching was accompanied by synchronous color switching.  相似文献   
25.
Reaction of rhodium trichloride with a new ligand, oxyethylated calix[4]resorcinarene was examined in an inert atmosphere in different solvents (acetone, acetone + chloroform). The product was characterized by IR, Raman, 1H NMR, ESR, ESCA spectroscopy, conductometry. Its composition was proved by the data of elemental and X-ray fluorescent analyses. The solvent used does not affect the composition of the product but only its yield. The structure of the coordination node and the type of coordination of the rhodium-containing fragment was investigated by calculating the model molecules of the ligand and the complex using the molecular mechanics method (MM+).  相似文献   
26.
Phosphorylation of alkylated polyethyleneimine in chloroform in the presence of alkylated calyx[4]-resorcinolarenes with 2-hydroxyethoxy- and phosphorus-containing substituents and cetyl(3-hydroxypropyl)-dimethylammonium bromide was studied by means of the UV spectrophotometry. It was found that the character and the degree of the effect of calyxarene and its mixture with the surfactant depend on the hydrophobicity of macroring and the ratio of concentrations of components in the solution. The increase in the content of calyxarene and decrease in the concentration of polymer leads to the transformation of the catalytic action into the inhibiting one.  相似文献   
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Russian Journal of General Chemistry - The Kabachnik–Fields reaction in a ternary system of 4,4-diethoxybutylamine–dialkyl(tolyl)-phosphine...  相似文献   
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