Cellulose is one of the most abundant natural polymers in the nature, which has many attractive advantages, such as renewability,biodegradability, and biocompatibility. However, due to the strong hydrogen bond network and hierarchical structure, cellulose is extremely difficult to be dissolved and processed. More recently, a class of novel eco-friendly solvents, ionic liquids, have been found to be able to efficiently dissolve cellulose, providing a versatile platform for cellulose processing an... 相似文献
Metal sulfides are among the most promising materials for a wide variety of technologically relevant applications ranging from energy to environment and beyond. Incidentally, ionic liquids (ILs) have been among the top research subjects for the same applications and also for inorganic materials synthesis. As a result, the exploitation of the peculiar properties of ILs for metal sulfide synthesis could provide attractive new avenues for the generation of new, highly specific metal sulfides for numerous applications. This article therefore describes current developments in metal sulfide nanoparticle synthesis as exemplified by a number of highlight examples. Moreover, the article demonstrates how ILs have been used in metal sulfide synthesis and discusses the benefits of using ILs over more traditional approaches. Finally, the article demonstrates some technological challenges and how ILs could be used to further advance the production and specific property engineering of metal sulfide nanomaterials, again based on a number of selected examples. 相似文献
Abstract The Knoevenagel condensation of aromatic aldehydes with (2‐thio)barbituric acid proceeded efficiently in reusable ionic liquids, EAN, BmimBF4, and BmimPF6 at room temperature in the absence of any catalyst with high yields. 相似文献
1-(α-Alkoxyalkyl)benzotriazoles are readily synthesized from three-component condensation of benzotriazole with aldehyde and alcohol in ionic liquid [Bmim]PF6. 相似文献
A new type of ionic liquids containing cation of diacetone acrylamide [or N-(1,1-bismethyl-3-oxo-butyl)acrylamide]and anions such as CH3COO^-(Ac),CF3COO^-(TF),BF4^-(BF),PF6^-(PF),HSO4^-(SO) and Cl^-(Cl) were prepared by normal neutralization.The obtained ionic liquids were identified by FT-IR and ^1H NMR spectroscopy.However,their properties such as meliting point,conductivity,viscosity etc,were determined. 相似文献
An efficient esterification of ferrocenecarboxylic acid with substituted phenols has been achieved using DCC / DMAP protocol in ionic liquids. The corresponding esters are produced in high yields. 相似文献
Currently ionic liquids (ILs) are attracting considerable interest as eco-friendly solventsfor the replacement of volatile organic solvents in organic synthesis and catalysis1.Low-melting ILs based on imidazolium cations have dominated this area over the … 相似文献
Novel ionic liquids with dual acidity, of which the cation contains Brφnsted acidity and anions contain Lewis acidity were synthesized. These ionic liquids obtained were identified by NMR, FF-IR, SDT and FAB-MS. Their acidities were determined by pyridine probe on IR spectrography. 相似文献
Room temperature ionic liquids were used as a “green“ recyclable alternative to conventional solvents in the synthesis of pharmaceutically useful compounds 2-arylimidazo[1, 2-a]pyrimidines through Tschotschibabin reaction of a-bromoacetophenones with 2-aminopyrimidine in good yields. 相似文献
Recycling of “green” solvents : Recycling of ionic liquids with high efficiency is of key importance on going from the laboratory‐scale to large‐scale industrial application of these solvents.
The sorption of CO2 is often used to modify the macroscopic properties of liquids and solids. In the particular case of ionic liquids, different from molecular liquids, the sorption of CO2 may not induce volume expansions due to the strong Coulombic interactions between the ions of the fluid. However, a considerable viscosity decrease has been systematically observed. In order to understand the mechanisms of properties modifications in ionic fluids, herein we used Raman spectroscopy to probe the effect of CO2 on the structure of ionic liquids. It is shown that CO2 perturbs the electrostatic interactions between cations and anions, thus inducing a change in the polar domain of ionic liquids. It is observed that ionic liquids having bulkier ions are more prone to be perturbed by CO2 in comparison to ionic liquids having smaller ions. These results reveal new means of controlling the electrostatic forces between the ions and contributes to the mechanistic understanding of the modification of the macroscopic properties of ionic liquids by CO2 sorption. 相似文献
The kosmotropicity of cations and anions in ionic liquids has a strong influence on the enzyme catalytic efficiency in aqueous environments. The kosmotropic anion CF3COO^- seemed to activate the protease, and the chaotropic anions tended to destabilize the enzyme. 相似文献
The surfactant TX-100 can be dissolved in ionic liquid bmimPF6 and decrease the surface tension of 1-buty1-3-methylimidazolium hexafluorophosphate (bmimPF6) solutions. Here, we confirmed that in this new system, the pure solvents need rearrangement at the air-wate rinterface at the initial stage. The dynamic surface tension (DST) study shows that at the initial adsorption stage, the adsorption model of surfactant accords with the diffusion-controlled adsorption mechanism, and the dilute ionic liquids solutions is further close to the diffusion-controlled adsorption. 相似文献
Ionic liquids are credited with a number of unusual properties. These include a low vapor pressure, a wide liquid‐phase range, weakly coordinating properties, and a high thermal/chemical stability. These properties are certainly of great interest for inorganic synthesis and the creation of novel inorganic compounds. On the other hand, the synthesis repertoire for preparing inorganic compounds has always been broad, ranging from syntheses in solutions and melts to solid‐state reactions, and from crystal growth in the gas phase to high‐pressure syntheses. What new aspects can ionic liquids then add to the synthesis of inorganic compounds? This Minireview uses some early examples to show that the use of ionic liquids indeed provides access to unusual inorganic compounds. 相似文献
Lewis acidic ionic liquids have been receiving extensive interest as green substitute for H2SO4, HF and AlCl3 catalysts in chemical processes1. In view of the principles of green chemistry2, ionic liquids themselves are highly expected to be obtained via … 相似文献
On the basis of their characteristic polar nature, phase behavior and lack of vapour pressure, ionic liquids are considered as green solvents and have attracted significant attention as an alternative reaction medium for homogeneous catalysis.[1] However, the "greenness" of typical ionic liquids used in the literature consisted of halogen-containing anions (such as [AlCl4]-, [BF4]- and [PF6]-) was limited in some sense, due to the serious environment concerns if the hydrolysis stability of the anion is poor (e.g. for [AlCl4]-and [PF6]-) or thermal stability of used ionic liquid is undesired. In both cases, the additional effort is needed to avoid the liberation of toxic and corrosive HF or HCl into the environment. 相似文献
Abstract Aromatics nitrate with NO2/air catalyzed by novel Brønsted acidic ionic liquids (ILs) without any volatile chlorinated organic solvent under mild conditions. The ILs employed were caprolactam based, [Caprolactam]X (X?=pTSO?, BSO?, BF4?, NO3?), which are of relatively lower cost and lower toxicity than traditional imidazolium‐based ILs. The nitration reactions were carried out at ?15 to ?0°C first, then at room temperature for a longer time with a little excessive NO2 (ca. 1.4 eqv.) for moderate yield (for toluene). The IL could be reused four times. 相似文献