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1.
The complexes [Et2NH2] 3 + [BiCl6]3? (I), [NH4]+[BiI4(C5H5N)2]?·2C5H5N (II), [Ph3MeP] 2 + [BiI5]2? (III), [Ph3MeP] 2 + [BiI5(C5H5N)]2?·C5H5N (IV), [Ph3MeP] 3 + [Bi3I12]3? (V), [Ph3(i-Pr)P] 3 + [Bi3I12]3?·2Me2C=O (VI), [Ph3BuP] 2 + [Bi2I8·2Me2C=O]2? (VII), and [Ph3BuP] 2 + [Bi2I8·2Me2S=O]2? (VIII) were obtained by reactions of bismuth iodide with ammonium and phosphonium iodides in acetone, pyridine, or dimethyl sulfoxide.  相似文献   

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3.
From the dependence of the molal osmotic coefficients of (hept)4NX (X = Cl, Br, J), (hept)4NNO3 and (oct)4PNO3, in benzene at 33, 40 and 50°C, on the solute concentration, the dimerization constants of solute ion-pairs and the corresponding thermodynamic functions of dimerization, ΔG°, ΔH° and ΔS° have been calculated. The thermodynamic data are discussed in terms of a simple electrostatic model of association.  相似文献   

4.
Two series of wedge-shaped onium salts, one ammonium and the other phosphonium, having 3,4,5-tris(alkyloxy)benzyl moieties, exhibit thermotropic bicontinuous "gyroid" cubic (Cub(bi)) and hexagonal columnar liquid-crystalline (LC) phases by nanosegregation between ionophilic and ionophobic parts. The alkyl chain lengths on the cationic moieties, anion species, and alkyl chain lengths on the benzyl moieties have crucial effects on their thermotropic phase behavior. For example, triethyl-[3,4,5-tris(dodecyloxy)benzyl]ammonium hexafluorophosphate forms the thermotropic Ia3d Cub(bi) LC phase, whereas an analogous compound with trifluoromethanesulfonate anion shows no LC properties. Synchrotron small-angle diffraction intensities from the Ia3d Cub(bi) LC materials provide electron density maps in the bulk state. The resulting maps show convincingly that the Ia3d Cub(bi) structure is composed of three-dimensionally interconnected ion nanochannel networks surrounded by aliphatic domains. A novel differential mapping technique has been applied successfully. The map of triethyl-[3,4,5-tris(decyloxy)benzyl]ammonium tetrafluoroborate has been subtracted from that of the analogous ammonium salt with hexafluorophosphate anion in the Ia3d Cub(bi) phases. The differential map shows that the counteranions are located in the core of the three-dimensionally interconnected nanochannel networks. Changing from trimethyl- via triethyl- to tripropylammonium cation changes the phase from columnar to Cub(bi) to no mesophase, respectively. This sensitivity to the widened shape for the narrow end of the molecule is explained successfully by the previously proposed semiquantitative geometric model based on the radial distribution of volume in wedge-shaped molecules. The LC onium salts dissolve lithium tetrafluoroborate without losing the Ia3d Cub(bi) LC phase. The Cub(bi) LC materials exhibit efficient ion-transporting behavior as a result of their 3D interconnected ion nanochannel networks. The Ia3d Cub(bi) LC material formed by triethyl-[3,4,5-tris(decyloxy)benzyl]phosphonium tetrafluoroborate shows ionic conductivities higher than the analogous Ia3d Cub(bi) material based on ammonium salts. The present study indicates great potential of Cub(bi) LC nanostructures consisting of ionic molecules for development of transportation nanochannel materials.  相似文献   

5.
A combination of a phosphonium-type-zwitterions-lithium bis(trifluoromethanesulfonyl)imide complex and a hydrophilic ammonium salt provides a nanosegregated liquid-crystalline matrix consisting of hydrophilic ionic liquid (IL) domains and hydrophobic IL domains.  相似文献   

6.
It was shown that it is possible to use a series of ammonium and phosphonium salts as effective catalysts for the preparative synthesis of tris(polyfluoroalkyl) phosphates. The effect of the structure of substituted ammonium salts on their catalytic activity was studied in the phosphorylation of 1,1-dihydroperfluorobutanol by phosphorus oxychloride. It was determined that the reaction rate is affected not only by the solubility of the salt, but also by the nature of the ion pair and the steric access of the onium center for solvation by phosphoryl compounds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2789–2792, December, 1989.  相似文献   

7.
Triphenyl(3-phenylprop-1-ynyl)phosphonium bromide (3) was isolated. This compound is a third isomer for the tautomeric system triphenyl(3-phenylpropadienyl)phosphonium bromide (1) triphenyl(3-phenylprop-2-ynyl)phosphonium bromide (2). Salts 1 and 2 smoothly react with secondary amines to give adducts with an ,-double bond, while salt 3 changes to an allene ylide. Addition of phenylhydrazine and triphenyl(phenylethynyl)phosphonium bromide to salts 1 and 2 and addition of dimethylformamide to salt 2 were performed.  相似文献   

8.
The synthesis and mechanism of formation of phosphonium salts of the type [R3P+CFXY]Z? (where X = F, Cl, Br; Y = Br, Cl; Z = Br, Cl), bis-phosphonium salts of the type [R3P+CF2P+R3]2Br?, and phosphoranium salts of the type [R3P+C?FP+R3]X? (X = Br, Cl) will be presented. The applicability of these substrates in the generation of useful nucleophilic or electrophilic synthetic intermediates will be discussed.  相似文献   

9.
The nickel-catalyzed synthesis of phosphonium salts from aryl halides and triphenylphosphine is reported.The formation of phosphonium salts occurs by the oxidative addition reaction of Ni[P(C6H5)3]3 on the aryl halides and reaction of the coordinated aryl groups with triphenylphosphine.The influence of substituents on the aromatic nucleus is studied.  相似文献   

10.
Bromide and iodide ions were determined simultaneously by capillary isotachophoresis using an aqueous electrolyte system; the separation principle was based on the ion-pairing equilibria between tetradecyldimethylbenzylammonium ion and these anions in the leading electrolyte. The interaction between iodide ion and tetradecyldimethylbenzylammonium ion was stronger than that for bromide ion. Thus complete separation of bromide and iodide ions could be obtained by using a leading electrolyte containing 1.5 mM tetradecyldimethylbenzylammonium ion. The pH of the leading electrolyte was adjusted to 5.0. The relative standard deviations of the zone length for bromide and iodide ions were 1.1 and 1.2%, respectively, when mixture of 3.0 mM of these ions was analysed. A 150-μl volume could be injected for the simultaneous determination of low concentrations of bromide and iodide ions.  相似文献   

11.
The reactions between nitron, quinine, cinchonine, strychnine, sparteine, papaverine, rivanol, acriflavine, phenanthroline, antipyrine and atropine with bismuth nitrate in potassium iodide solution were studied heterometrically. The individual structure of the N-compounds was discussed on the basis of the reactions and the large salt-compounds obtained 0.5 to 1 mg of N-compound was necessary for a determination which lasted 10–15 min. The errors in almost all cases were negligible 0.3–0.5 mg bismuth could also be determined by the titration of bismuth with N-compounds and the error was negligible.  相似文献   

12.
Phosphonium salts have been prepared during high-energy ball-milling of triphenylphosphine with solid organic bromides; the reactions occur at ambient conditions without a solvent; in the case of 2-bromo-2-phenylacetophenone the reaction in a solution usually produces a mixture containing both the C-phosphorylated and O-phosphorylated compounds, while the solvent-free mechanically induced transformation results in the thermodynamically favorable C-phosphorylated product; the occurrence of the observed transformations during mechanical processing of solid reactants is confirmed by the solid-state 31P NMR spectroscopy and X-ray powder diffraction.  相似文献   

13.
《Mendeleev Communications》2020,30(6):700-702
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《Mendeleev Communications》2023,33(4):491-493
gem-Difluorinated phosphonium salts were generated from nitrones by methylation and reaction with (triphenylphosphonio)difluoroacetate. The phosphonium salts were subjected to visible light-induced phosphonium–thiocyanate exchange in the presence of ammonium thiocyanate, copper thiocyanate, and an iridium photocatalyst. The sequence of the reactions was performed in one pot affording thiocyanates attached to the difluoromethylene fragment.  相似文献   

16.
The reaction of 2- or 4-methyl-2,6-diphenylpyrylium perchlorate with tetracyanoethylene (TCNE) in pyridine gives 2- or 4-(2,3,3-tricyanopropylidene)-2,6-diphenylpyran in good yield. Similar results are obtained from 2- or 4-methyl-2,6-diphenylthiapyrylium and 4-methylflavylium perchlorates. In one case a stable charge-transfer salt is isolated from the reaction of a methylene base and TCNE. The reaction mechanism of dye formation is discussed.  相似文献   

17.
Quaternary ammonium salts were synthesized from ammonium salts and dialkyl carbonates over an ionic liquid catalyst 1-ethyl-3-methylimidazolium bromide.  相似文献   

18.
Russian Chemical Bulletin - Earlier unknown crystalline forms of three carboxylate phosphabetaines and conjugated with them phosphonium salts differing by β substituent with respect to the...  相似文献   

19.
The optimum iodide concentration (excess) for the extraction of bismuth as Bil3 into isoamyl acetate from 1—5 N sulfuric acid solution is approximately 5.10-3M. At this iodine concentration the extraction coefficient [Bi] isoamyl acetate/[Bi]H2O is approximately 130 (25-30°) when the ratio of isoamyl acetate to aqueous phase is 1 : 4. Mixturcs of isoamyl acetate and isoamyl alcohol in the proper ratios extract Bil3 to a greater extent than either solvent alone.  相似文献   

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