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1.
Complex formation and self-association in the system alkylated polyethyleneimine-calix[4]resorcinarene-chloroform were studied by UV spectrophotometry, dilecometry, and light scattering. The constant of complex formation of polyethyleneimine with calixarene was found to depend on the hydrophobicity of the components of the system and presence of surfactants.  相似文献   

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Aggregation of 1-hexadecyl-4-aza-1-azoniabicyclo[2.2.2]octane bromide in the presence of diethyl 4-nitrophenyl phosphate was studied using 1H NMR spectroscopy. The quantitative characteristics of the aggregation were determined. The data obtained were used to explain the catalytic effect of micelles on the hydrolysis of the phosphate. It was found that the aggregation properties and biological activity of alkylated mono- and dicationic 1,4-diazabicyclo-[2.2.2]octanes are correlated.  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   

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[reaction: see text] Three extended [4]radialenes with two tricyclic rings connected with exocyclic butatriene units have been synthesized. The compounds, possessing thioxanthene and dihydroanthracene moieties as the terminal substituents, show a fast rotation around the butatriene bonds at ambient temperatures (DeltaG() = 13.7 and 14.9 kcal/mol, respectively). In contrast, the fluorene-substituted analogue shows a much higher rotational barrier (DeltaG() = 17.8 kcal/mol) of the butatriene bonds due to the reduced steric repulsion between the two fluorene moieties at the ground state.  相似文献   

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About the Na5[GaO4]-Relationship: KNa4[GaO4] and CsK4[GaO4] KNa4[GaO4] was newly prepared from binary oxides (powders) and also from KGaO2/Na2O/K2O (colourless columnar single crystals) in a closed Ag-cylinder at 600 and 650°C. Space group Pbca with a = 1046.1(2), b = 596.3(1), c = 1871.1(3) pm, Z = 8 [Four-circle-diffractometer data, 1138 I0(hkl), MoKα, R = 8.29, Rw = 6.76%, anisotropic refinement] (Parameter s. text). Colourless cubic single crystals of hitherto unknown CsK4[GaO4] are formed by reaction of K2O, CsGaO2, and Cs2O (surplus) in a closed Au-tube at 580°C. Space group Pbca with a = 1154.7, b = 667.7, c = 2096.6 pm, Z = 8 [Four-circle-diffractometer data, 1798 I0(hkl), MoKα, R = 7.62, Rw = 7.68%, anisotropic refinement] (Parameter s. text). Both crystal structures belong to the Na5[GaO4] type. Structural aspects, ECoN, and MAPLE of KNa4[GaO4] and CsK4[GaO4] in relation with Na5[GaO4] are discussed.  相似文献   

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The condensations of 1-(2-hydroxyphenyl) pyrroles with a variety of carbonyl compounds are shown to give new 4-substituted-4H-4-methylpyrrolo[2,1-c][1,4]benzoxazines. Some of the products were further functionalized. The ir, uv, and pmr spectra of the title heterocyclic system are discussed. Reaction of 1-(2-hydroxyphenyl) pyrrole with dimethyl acetylenedicarboxylate yielded dimethyl 3-(2-hydroxyanilino) phthalale; a mechanistic rationale which accounts for the result involves a rearrangement of the hypothetical Diels-Alder adduct.  相似文献   

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4H-[1]benzopyrano[3,4-c][1,2,5]selenodiazol-4-one has been synthesized by the reaction of 3,4-diaminocoumarin with selenous acid and its reaction with several nucleophiles (alkali, ammonia, amines, hydrazine hydrate) and its nitration have been studied. Using PMR spectroscopy, a comparative kinetic study of the opening of the lactone ring in 6,8-dinitro-4H-[1]benzopyrano[3,4-c][1,2,5]seleno- and thiadiazol-4-ones has been carried out.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 128–133, January, 1991.  相似文献   

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Calix[4]azulene     
Azulene reacts with paraformaldehyde in the presence of florisil to give excellent yields of calix[4]azulene.  相似文献   

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Synchrotron radiation X-ray powder diffraction data (SPDD) have been obtained for Ag[AgF4]2, Au[AuF4]2, Ag[AuF4], and Ag[AuF6]. Ag[AgF4]2 and Au[AuF4]2 are isostructural with Ag[AuF4]2, space group (SG) P2(1)/n, Z = 2, with the following: for Ag[AgF4]2 a = 5.04664(8), b = 11.0542(2), c = 5.44914(9) A, beta = 97.170(2) degrees; for Au[AuF4]2 a = 5.203(2), b = 11.186(3), c = 5.531(2) A, beta = 90.55(2) degrees. The structure of Ag[AgF4]2 was refined successfully (SPDD) applying the Rietveld method, yielding the following interatomic distances (A): AgII-F = 2.056(12), 2.200(13), 2.558(13); AgIII-F = two at 1.846(12), others = 1.887(12), 1.909(13), 2.786-(12), 2.796(12), 2.855(12). AgAuF4, like other AA'F4 salts (A = Na-Rb; A' = Ag, Au), crystallizes in the KBrF4 structure type, SG I4/mcm (140), Z = 4 with a = 5.79109(6), c = 10.81676(7) A. SPDD gave (in A) four AuIII-F = 1.89(1) and eight AgI-F = 2.577(7). SPDD for AgAuF6 confirmed that it has the LiSbF6 structure, SG R3, Z = 3, with a = 5.2840(2), c = 15.0451(6) A.  相似文献   

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The review deals with the synthesis, chemical modification, and complexing properties of a new class of molecular receptors, porphyrin-calix[4]arene conjugates.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 807–826.Original Russian Text Copyright © 2005 by Mamardashvili, Koifman.  相似文献   

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The First Oxide with the Formula Type K5[MO4]: K5[TlO4] Light yellow powder and pale yellow transparent single crystals of K5[TlO4] were newly prepared from mixtures of binary oxides (K2O/Tl2O3) preheated and levigated several times [closed Ag-cylinder, 580°C, 24 h and 600°C, 20 d]. Space group Pbca with a = 1170.4(3), b = 686.1(1), c = 2079.2(5) pm, Z = 8 [four-circle-diffraktometer data, 997 I0(hkl), R = 7.87%, Rw = 5.63%, MoKα] (parameter s. text). The crystal structure belongs to the Na5[GaO4] type. Structural aspects, ECoN and MAPLE are discussed.  相似文献   

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