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1.
Acid-base properties of newly and previously synthesized phosphorylated azapodands and ??,??-diamines and their amine precursors were studied. We found that they differ in the same range as has been found previously for the other aminophosphoryl compounds. The investigation of the processes of passive membrane ion transport of a series of metals of I?CIII groups by these reactants showed with all diphosphoryl diamines higher values of the transfer flow of the ions Sc(III), Nd(III), and Sm(III), than the ions of alkali and alkaline earth metals. Under the conditions of active membrane transport the azapodand IV exhibits high efficiency in the ion transport of Sr(II) and Ba(II), while diphosphoryldiamine III exhibits effective transport of Nd(III) ions. The factors that determine the efficiency and selectivity of the membrane extraction of the I?CIII groups metal ions by these diphosphoryl diamines are discussed.  相似文献   

2.
New cesium-selective electrodes containing as an electrode active substance biphosphorylated azapodands: 1,8-bis(dioctylphosphorylmethylamino)-3,6-dioxaoctane (I), 1,10-bis(dioctylphosphorylmethylamino)-4,7-dioxadecane (II), and 1-(dioctylphosphorylmethylamino)-10-[(dioctylphosphorylmethyl)benzylamino]-4,7-dioxadecane (III) were developed, and the composition of the membranes of these electrodes was optimized. The high selectivity of electrodes based on the ionophores I–III toward Cs(I) ion, which can be determined on the background of the majority of the other ions of alkali and alkaline earth metals, including the close to it by size Rb(I) ion, was established.  相似文献   

3.
《European Polymer Journal》1996,32(9):1037-1044
The synthesis of a functional polysilane, α,ω-dichloro-polymethylphenylsilane (α,ω-dichloro-PMPS), based on the Wurtz-type reductive coupling, has been considered. A study of some reaction parameters shows that both yield and molecular weight distribution of α,ω-dichloro-PMPS can be greatly influenced by the work-up conditions, reaction time, monomer concentration and temperature during the initiation of the polymerization. By varying the synthesis conditions, different ratios of high and low molecular weight fractions were obtained. Samples of different molecular weight were isolated by fractional precipitation of the crude polymers. The chlorine-end functionalization was confirmed by 29Si NMR spectroscopy and the concentration of end-groups was quantitatively determined by elemental analysis of chlorine.  相似文献   

4.
《European Polymer Journal》1986,22(11):877-887
α-Amino (MAO) and α,ω-diamino (DAO) oligoamides were prepared using dodecylamine or 1,6 diaminohexane as a chain limitator. These were characterized by GPC, 1H-NMR and 13C-NMR; molecular models: N-dodecyldodecanamide and 1,6 bis dodecylaminohexane; trifluoroacetylation was used to dissolve the oligoamides. DAO prepared in the melt contains two types of chains, depending on the position of the limitator. When oligomers were prepared in solution using the Yamazaki method, the presence of residual phosphorus derivatives in the oligoamides could not be avoided.  相似文献   

5.
Summary By the action of sodium in xylene on polychloro hydrocarbons containing -CCl2-CCl2- or- CC1=CC1-, groupings the corresponding symmetrical acetylenic hydrocarbons containing 10,14, and 18 carbon atoms in the molecule were obtained. From ,-disubstituted tetrachloroalkanes by the same method 1,10-diethoxy-5-decyne, 1,14-diethoxy-7-tetradecyne, and 1,14-bisdiethylamino-7-tetradecyne were obtained.The spectra were determined in the Optical Laboratory of the Institute of Heteroorganic Compounds of the USSR by N. A. Chumaevskii, who we thank.  相似文献   

6.
7.
A novel set of dimers derived from 9-amino acridine was prepared and characterized by1H and13CNMR. These derivatives are bridged at several different positions of the heterocyclic moieties, by the way of ,-diamido or ,-diamino side-chains. Additionally the preparation of some bi-bridged compounds was achieved.
Neue ,-Dimaido- und ,-Diamino-Mono- und Bi-überbrückte Acridin-Dimere
Zusammenfassung Es wurde eine neue Reihe von Dimeren des 9-Aminoacridins hergestellt und mittels1H und13C-NMR charakterisiert. Diese Derivate sind an verschiedenen Positionen des Heterocyclus mit ,-Diamido- oder ,-Diamino-Seitenketten überbrückt. Zusätzlich wurden auch einige zweifachüberbrückte Verbindungen hergestellt.
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8.
A series of α-N,N-dihydroxyethylaminopropyl-ω-butylpolydimethylsiloxanes with different molecular weight were synthesized. The preparation included five steps which were hydroxyl protection, alkylation, anionic ring-opening polymerization, hydrosilylation and deprotection. The structure of reaction products was characterized by FT-IR, GC, 1H NMR. 2007 Qing Si Zhang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.  相似文献   

9.
Liquid extraction from the aqueous solutions of perchloric acid with neutral azapodand extractant N,N′-bis(dioctylphosphorylmethyl)-1,8-diamino-3,6-dioxaoctane has been highly efficient in the cases of uranyl ions and some metals of groups II and III. To estimate the synergic effect of organophosphorus extractants, the neutral extractant was applied in the mixture with an acidic component, bis(pentadecyl)phosphoric acid. The synergic effect has exclusively been observed in the extraction of zinc and cadmium ions.  相似文献   

10.
Abstract

ω-Vinylpolydimethylsiloxanes (ω-PDMS) and α,ω-divynilpolydimethylsiloxanes (α,ω-PDMS) have been synthesized by anionic polymerization of hexamethylcyclotrisiloxane (D3). The reactions were carried out in n-hexane and tetrahydrofuran (THF), respectively. The initiator was n-butyl-lithium (n-BuLi); tetrahydrofuran was used as an electron donor compound to promote the polymerization of D3. The synthesized polymers have been characterized by infrared (FTIR), proton nuclear magnetic resonance spectroscopy (NMR), light scattering (LALLS), and gel permeation chromatography (GPC). Molecular weights ranging from 20,000 to 100,000 were obtained with relatively narrow molecular weight distributions; Mw/Mn < 1.25.  相似文献   

11.
Processes of extraction of ions of the I–IV group metals from acidic water solutions with paraffin quasiliquid emulsions containing neutral phosphorylazapodand, bis(dioctylphosphorylmethyl)-1,8-diamino-3,6-dioxaoctane I, and acidic components, bispentadecylphosphoric II and hexadecylsulfonic acid III is studied. High effectiveness of extraction of metal ions with these extraction compositions is established. It significantly exceeds the effectiveness of liquid extraction in the same systems, especially of ions of the II group metals. The extraction of three-charged ions proceeds more effectively by the mixture of organophosphorus reagents I and II, than with the composition consisting of azapodand I and organosulfur acid III.  相似文献   

12.
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15.
Cyclization of esters of butane-1,1,4,4- and pentane-1,1,5,5-tetracarboxylic acids during electrolysis in methanol in the presence of Nal produces, with a yield of 95%, the esters of cyclobutane-1,1,2,2- and cyclopentane-1,1,2,2-tetracarboxylic acids. Under similar conditions, esters of the highest ,,,-alkanetetracarboxylic acids undergo iodation and hydroxymethylation due to electrical oxidation of methanol to formaldehyde. During electrolysis in methanol in the presence of NaOAc, the esters of ,,,-alkanetetracarboxylic acids undergo effective hydroxymethylation, followed by cyclization into substituted five- and six-member lactones, or tetrahydrofurans when structurally possible.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2332–2339, October, 1992.  相似文献   

16.
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18.
《Tetrahedron》1987,43(2):361-364
The synthesis of some α,α,ω,ω-tetrachloro and tetrabromo-derivatives of the hypolipidemic 3,3,14,14-tetramethylhexadecanedioic acid from α,ω-dihalo-esters, carbon tetrahalides and lithium diisopropyl amide has been described. Interaction of α,ω-dichloro esters with CBr4 was shown to give the expected α,ω-dibromo-α,ω-dichloro compounds, but treatment of bis(l-methylethyl) 2,15-dibromo-3,3,14,14-tetramethylhexa-decanedioatewith CCl4 was found to result in halogen exchange yielding the tetrachloro-diester as the major product.  相似文献   

19.
The stability of Si-Si bonds in linear and cyclic permethyloligosilanes and in ,-divinyloligosilanes under conditions of hydrosilylation in the presence of the Speier's catalyst was studied. Polycarbosilanes containing silylene fragments in their backbone chains were prepared by the reaction of 1,4-bis(dimethylsilyl)benzene with ,-divinyloligosilanes. It was found that the structure of these polymers is disturbed due to the side reaction involving the cleavage of the Si-Si bond in vinyloligosilanes under the action of H2PtCl6.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2547–2549, October, 1996.  相似文献   

20.
Abstract

Molar excess enthalpies, H E m, at 298.15K and atmospheric pressure have been determined for three binary liquid mixtures [x{1,3-dichloropropane or 1,4-dichlorobutane and 1,6-dichlorohexane} + (1 - x) tetrachloromethane]. These experimental results along with the data available in the literature on molar excess Gibbs energies, G E m, activity coefficients at infinite dilution, In γ i , and molar excess enthalpies, H E m, for α,ω-dihaloalkanes + benzene or + tetrachloromethane mixtures are examined on the basis of the DISQUAC group contribution model.  相似文献   

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