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1.
The following reactions of pyrylium salts with amines are described: (1)bis(pyrylium salts) with amines; (2) diamines with pyrylium salts; and (3) bis(pyrylium salts) with diamines. Both (1) and (2) give bis(pyridinium salts) in high yields, and (3) gives the corresponding polymers which are isolated and characterized. This procedure was applied to cationic bis(pyrylium salts) to give cationic dimers and polymers, and further to zwitterionic bis(pyrylium salts) to yield the corresponding zwitterionic dimers and polymers.  相似文献   

2.
含能盐和含能离子液体   总被引:15,自引:0,他引:15  
近年来含能盐和含能离子液体由于其独特的性质而受到广泛关注。本文综述了多种含能盐和含能离子液体(阳离子包括三唑、四唑、双环唑、六次甲基四胺等;阴离子包括硝酸根、高氯酸根、硝基唑、叠氮根、四硝基铝、多腈基化合物、二硝基尿素等)的合成;结合其表征结果分析了阳离子上的取代基以及阴阳离子对它们的性能如熔点、生成焓、密度等的影响。对含能盐和含能离子液体在炸药和推进剂方面的应用进行了展望。  相似文献   

3.
硝基四唑及其高氮化合物*   总被引:6,自引:0,他引:6  
硝基四唑及其高氮化合物是指分子中含有5-硝基四唑结构的一类高氮化合物,优越的性能和突出的特点使其成为含能材料领域的研究热点之一,在起爆药、推进剂及其燃速催化剂、高能炸药、气体发生剂等领域有着广泛的应用前景。本文对硝基四唑的结构与热分解机理进行了分析介绍;全面系统地综述评价了硝基四唑及其盐类和配合物类衍生物的合成、性能表征与应用前景。根据其成盐阳离子的不同,硝基四唑盐类主要包括碱金属盐、碱土金属盐、过渡金属盐、胺盐和高氮杂环阳离子盐。根据配位方式的不同,其配合物可分为配阴离子型和配阳离子型。在此基础上,对硝基四唑及其高氮化合物的未来发展及应用提出了展望。  相似文献   

4.
Poly(o‐methoxyaniline) (POMA) and poly(o‐toluidine) (POT) salts doped with different acids (methanesulphonic acid (MeSA), trifluoroacetic acid (TFA), and hydrochloric acid (HCl)) were synthesized by using solid‐state polymerization method. The polymers were characterized by Fourier transform infrared (FTIR) spectra, ultraviolet–visible (UV–Vis) spectrometry, X‐ray diffraction (XRD), cyclic voltammetry (CV), and conductivity measurements. Transmission electron microscopy (TEM) was done to study the morphologies of POMA and POT salts. The FTIR and UV‐Vis absorption spectra revealed that the reduced phase was predominant in POMA salts, and the pernigraniline phase was predominant in POT salts. It was found that POMA salts displayed higher doping level and conductivity. In contrast, POT salts were lower at doping levels and conductivity. In accordance with these results, the electrochemical activity was also found to be lower in POT salts. The XRD patterns showed that the POMA salts displayed higher crystallinity than POT salts. The results from TEM revealed that the morphologies of POMA salts were different from those of POT salts. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

5.
Acidic 1,3-azolium salts are prepared from Brønsted acids and 1,3-azoles such as imidazole, thiazole, and oxazole. Acidic imidazolium salts are frequently employed as promoters for the synthesis of nucleotides using the phosphoramidite method in a solution phase. Recently, it was revealed that thiazolium and oxazolium salts catalyzed Vorbrüggen-type N-glycosylation reactions to give nucleosides. These reactivities are attributed to the stronger Brønsted acidities of the thiazolium and oxazolium salts relative to those of the imidazolium salts. This digest focuses on recent progress in the applicability of acidic 1,3-azolium salts as promoters in the solution-phase synthesis of nucleosides and nucleotides.  相似文献   

6.
Abstract

The synthesis of 1, 2 vinylene bisphosphonium salts 1 has now been enlarged to the vinylogous 1, 4-butadienylene bisphosphonium salts 2. The salts 2, a new class of unsaturated disalts, have also been prepared through a two-step isomerisation of acetylenic salts. New aspects of the reactivity of salts 1 and the comparative study of salts 2 (selective cleavage reactions of P-C bonds and reactions with nucleophiles having a mobile hydrogen) are described. This reactivity allows the preparation of new series of phosphonium salts substituted by heteroatomic groups.  相似文献   

7.
Thermal ionization on the surface of a heated wire is applied to the volatilization products of alkali salts of carboxylic and sulfonic acids, and to quaternary ammonium salts. The mass spectra of the alkali salts exhibit almost exclusively cationized molecules. They provide evidence for the evaporation of intact clustered molecules even under conditions of a slow rate of evaporation of the salts. The method appears to be of interest for selective detection of alkali salts from complex mixtures. With the ammonium salts [R4N]+ ions are formed by thermal surface ionization of intact salt molecules. The evaporation of these molecules could be detected at rather low temperatures.  相似文献   

8.
Novel dialkylaminocarbenium salts with metallocomplex counter ions were prepared by the reaction of phosgene with either DMF or tetramethylurea in the presence of metal chlorides. Reactions of organosilicon amides with phosgene gave corresponding carbenium salts, while organosilicon ureas yielded aminoiminocarbenium salts. Dialkylaminochlorocarbenium salts were reduced with hydrosilanes to give dialkylaminocarbenium, salts and can be easily hydrolyzed to afford either amides or ureas. Pathways of the reaction with water and alcohols depend on the nature of reagent and the reaction conditions. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1035–1040, May 1997.  相似文献   

9.
In this paper, a separation method of radionuclides (Ba, Sr) from LiCl salt wastes generated from the electroreduction process of spent nuclear fuel was studied to recover pure LiCl salts and reduce radioactive wastes. The method consisted of chemical conversion process of BaCl2 and SrCl2 in LiCl molten salts by using lithium compounds and vacuum distillation process of LiCl salts. In the chemical conversion, BaCl2 and SrCl2 in LiCl molten salts were mainly converted into (Ba,Sr)CO3 or (Ba,Sr)SO4. Contents of Ba and Sr in LiCl salts recovered from the vacuum distillation process were equal to about 0.01 of initial concentrations of Ba and Sr in LiCl molten salts. These results will be utilized to recycle the LiCl salt wastes.  相似文献   

10.
Iodonium butyltriphenylborate salts (A I+ Ar′Ph3B R), (Bu) were found to be more efficient than iodonium tetraphenylborate salts (RPh) when used as photoinitiators for the polymerization of acrylates. Relative photodecomposition rates were also different. It was found from a study of the photoreaction of iodonium borate salts with a model monomer, methyl methacrylate, that iodonium butyltriphenylborate salts simultaneously produce a butyl radical from the borate anion and an aryl radical from the iodonium cation upon irradiation. Both radicals initiate polymerization. Iodonium tetraphenylborate salts were found to release an aryl radical, but only from the iodonium cation. Iodonium borate salts exhibit strong absorption below 300 nm with a tail absorption above 400 nm. Thus, iodonium butyltriphenyl borate salts are efficient photoinitiators even when used with visible light. When a photosensitizer such as 5,7-diiodo-3-butoxy-6-fluorone is employed, iodonium butyltriphenylborate salts are rendered much more efficient for visible light photopolymerization. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1667–1677, 1998  相似文献   

11.
The reaction of orthoesters with α- and γ-methylpyrylium salts gives 2- and 4-alkoxyvinyl-pyrylium salts the acid hydrolysis of which leads to 2- and 4-hydroxyvinylpyrylium salts and the alkaline hydrolysis to pyranylideneacetaldehydes.  相似文献   

12.
Two methods for the preparation of anilinopyrylium salts are described. The conversion of these salts to pyrans, pyridines, and nitrobenzenes is discussed. Azepines, benzimidazoles, and benxotriazoles are readily obtained from the o-aminoanilinopyrylium salts.  相似文献   

13.
Electron impulse in counts per second (CPS) of innermost electrons of solid salts, with water (aq) and aqueous glycine and DL-α-alanine with 0.5 M alkali salts solutions, at 35 kV and 1.5 mA were studied with Energy Dispersive Polarized X-ray Fluorescence (EDPXRF or XRF) around 0 to 12.5 keV energies. The CPS values derived from XRF spectra were regressed against concentrations for limiting CPS0 values. Different CPS values for each composition of salts and amino acids were noted due to hydration and salt-amino acid interaction. The XRF values illustrate ion-water-amino acid interactions. The CPS0 values are higher for solid salts(s) than those of aqueous and amino acids enhanced the CPS0 values of aq salts with stronger hydration energies (ΔG HE) due to perturbation of ion-dipole and ion-dipole-amino acid interactions. A quantum treatment for a response of innermost electron of salts is used to explain an ionic hydration. The CPS values of solid salts vary at a rate of 11944 as compared to aqueous solutions. The article is published in the original.  相似文献   

14.
Tetraalkyl ammonium (TAA) salts are of great importance in many areas of chemistry (organic, physical etc.). Tetraalkylammonium (TAA) chlorides, bromides or iodides are usually prepared by direct quaternization of trial-kyl amines with the corresponding alkyl halides. However other tetraalkylammonium (TAA) salts - cyanides, rhoda-nides, azides etc. cannot be prepared in this direct way. A typical method of preparation of these salts consists in ion exchange between available TAA halides and various salts containing the required anions. In some instances simply treating the TAA halides with aqueous solution of silver salts can be applied. This procedure, however, besides being costly is limited to the cases when the required silver salts are soluble in water1.  相似文献   

15.
36 kinds of mixed carbonate molten salts were prepared by mixing potassium carbonate, lithium carbonate, sodium carbonate in accordance with different proportions. The data of melting point and latent heat are measured by the analysis of DSC curves of 36 kinds of salts, which show that the majority of ternary carbonate’s melting points are close at around 400 °C. 24 kinds of eutectic molten salts were selected among 36 kinds of molten salts. With high latent heat, ternary carbonate salt has the potential to be employed for phase change thermal storage. The costs for phase change thermal storage of 24 kinds of carbonate salts are calculated. Finally, 13 kinds of ternary carbonate salts with lower cost for phase change thermal storage are recommended, where there are 6 kinds of mixed carbonates have the considerably larger latent heat of melting.  相似文献   

16.
Many alkali metal carboxylates when dissolved in poly(ethylene oxide) (PEO) oligomers, are phaseseparated by heating. These were revealed to be the crystals of the initially dissolved corresponding salts from the X-ray diffraction patterns. Some acetate salts achieve the lower limit of the lattice energy for phase separation of ordinary inorganic salts by heating in PEO oligomers. These carboxylate salts were therefore expected to show crystallization behavior in PEO oligomers by heating. The effects of cation size, alkyl chain length and molecular weight of PEO on the solubility are summarized. Negative temperature dependence of solubility of these acetate salts is seen in the PEO oligomers only when the salts have long alkyl chains. The salts containing larger cations needed a longer chain length of PEOs for crystallization by heating. These salts with longer alkyl chains showed positive temperautred dependence in lower molecular weight polyethers, but negative temperature dependence in solubility in PEO with molecular weights higher than 400. In PEO400, all the carboxylates with longer alkyl chains were phase separated by heating.  相似文献   

17.
A series of amino‐triazolium salts based on 4,5‐dicyano‐1,2,3‐triazolate (C4N5) anion were synthesized for first time by means of facile deprotonation reactions. The ionic compounds were characterized by single‐crystal X‐ray diffraction, vibrational spectroscopy, and elemental analysis. The thermal stability of the salts was assessed by differential scanning calorimetry, which showed good thermal stabilities up to above 180 °C. The heats of formation of these salts were computed using the methods of isodesmic reactions. In addition, the sensitivities of the studied salts toward impact and friction were determined, and all salts were found to be neither impact (> 40 J) nor friction sensitive (> 360 N).  相似文献   

18.
As a fundamental study on the development of dismantlable adhesives containing chemically reactive materials, the thermal behavior and dismantlability of an epoxy adhesive containing one of the twenty-seven inorganic salts (chlorides, perchlorates, and nitrates) were observed. In the thermal behavior measured by the differential scanning calorimetry, epoxy adhesives with inorganic salts containing iron, copper, zinc, and aluminum cations released heats of reaction at lower temperatures than the adhesive alone or the adhesives with other inorganic salts. Since such inorganic salts were considered to be effective candidates as fillers in dismantlable adhesives, the adhesion strengths of their mixtures with the adhesive were observed after heat aging at 270 °C for 30 min. The results showed that both chloride and perchlorate salts specifically decreased the adhesion strength after heating. On the other hand, the effect of nitrate salts on the decrease in adhesion strength was low in comparison with the chloride and perchlorate salts.  相似文献   

19.
The interaction between two modified ??-cyclodextrins and bile salts, common for rat, dog and man, was studied using isothermal titration calorimetry. The structural differences in the interaction were investigated by 13C NMR. The two modified ??-cyclodextrins were chosen because of their frequent use as oral excipients in drug formulation and in marketed products. All the investigated bile salts had an affinity for the ??-cyclodextrins, although there were large variations in the stability constants. The variations in the enthalpic and entropic contributions to the overall Gibbs free energy revealed differences in the binding mode to the investigated bile salts, i.e. the bile salts with a hydroxyl group at C12 interacted differently than bile salts without this hydroxyl group. These observations were supported by 13C NMR, which suggested binding to the D-ring of the steroid structure for bile salts with a hydroxyl group at C12 and to the C-ring for the bile salts without this hydroxyl group. The type of substitution of ??-cyclodextrin had significant effects on the thermodynamics of the interaction where especially the entropic changed were affected.  相似文献   

20.
Summary By the reaction of phosphorous acid and its salts and of hypophosphorous salts with paraform, hydroxymethylphosphonic acid and its salts and bishydroxymethylphosphinic salts were obtained in 90–93% yield.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1230–1233, July, 1964  相似文献   

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