| Ionic liquids(ILs) are composed of inorganic or organic anion andcation, and are liquids at ambient or far below100℃. There are manyunique and attractive physicochemical properties, including negligiblevapor pressure, excellent chemical and thermal stability, largeelectr-ochemical window, high ionic conductivity, solvation interactionswith organic and inorganic compounds. In addition, the physicochemicalproperties such as the viscosity, hydrophobicity, density, and solubilityof ILs can be tuned by simply selecting different combinations of cationsand anions as well as attached substituents to customize ILs for manyspecific demands.This is why ILs have been recognized as"designablesolvents."Worldwide in recent years due to the ionic liquid can no longer meetthe needs of scientific researchers, there formed the boom of functionalizedionic liquids, its main research direction is acidic ionic liquids, chiralionic liquids, coordinated ionic liquid, amino acid ionic liquids andcomposite ionic liquid.Recently, Br(?)nsted acidic ionic liquids, which combine both advantagesof solid acids(e.g. nonvolatility and easy recycle)and that of liquidacids(e.g. greater effective surface area and easy works),have beendesigned and used as dual solvent-catalysts for Fisheresterification,alcohol dehydrodimerization pinacol/benzopinacolrearrangements.Beckmann rearrangement as one of the important organic reactions,generally need to be completed under acidic conditions. In recent years,many organic chemists studied the Beckmann rearrangement in ionic liquid,but they need to add the auxiliary catalyst, such as PCl3, BDMS, Lewis acid, and it did not show the advantages of the ionic liquid as a green reagent.In view of the above analysis of the Br(?)nsted acidic ionic liquid as wellas the development of efficient, economic and environmentally friendlyBeckmann rearrangement catalyst system, in this paper, we synthesized sixkinds of cheap and easy to get Br(?)nsted acidic ionic liquid according tothe literature, to carry out applied research of Br(?)nsted acid ionic liquidsin the Beckmann rearrangement reaction, and got the following conclusions:(1) ionic liquid1a in this reaction has a very good catalytic effect oflow reaction temperature (100°C), short reaction time (1h).(2) In addition to aliphatic ketoxime did not get the desired results, thearomatic oxime to a high yield of rearrangement product (84%-92%), and thecatalytic activity of reused three times without significantly lower (87%,86%,84%).(3) oxime has good yield of dehydration product during the reaction (74%).(4) It didn't need to add any auxiliary catalyst in the catalyst system,the real green Beckmann rearrangement reaction.Enamine of diketone compounds is also the acid-catalyzed reaction,although in recent years there has developed many fast and efficientcatalysts, most of all are trying to enamine of ethyl acetoacetate oracetylacetone. The reports for5,5-methyl-cyclohexanedione is little orpoor catalytic effect, therefore, in this paper, we tried enamine reactionof5,5-dimethyl-cyclohexanedione in the aqueous phase with ionic liquids1a as catalyst. Compared to the traditional one, this catalytic system hasmany advantages:(1) The reaction used the green solvent water, and the experimentalprocedure is simple and high yield (65%-94%).(2) Post-processing is convenient, and can get the crude product withfiltration after the end of the reaction.(3) The filtrate can be reused as a catalytic system, to overcome the shortcomings of traditional ionic liquids which need to be further purified,and truly green.(4) The catalyst system reused for four times while the activity wasunchanged (89%,89%,88%, and88%).Amino acids as a very cheap and easy to get chiral source, ionic liquidsprepared by it has got more and more recognition and attention of scientists.Protic ionic liquids has been an important branch in the research of ionicliquids because of its simple and stable prepare methods. However, afterliterature review, we found that not been reported to the chiral group isintroduced into the anion of protic ionic liquids, the traditional aminoacid preparation of ionic liquids need to go through a complex synthesisprocess, limiting the development of amino acid ionic liquids. Therefore,in this paper, we combine the research status of the amino acid ionic liquidsand protic ionic liquids, made the following work:(1) Using N-BOC amino acids reacted with a variety of guanidine, imidazole,the first time the chiral group is introduced into the proton-type anions,and has got12kinds of novel chiral ionic liquids which were liquid at roomtemperature.(2) The synthetic method is simpler and more convenient than the traditionalamino acid preparation method of the ionic liquid as chiral source is easyto get.(3) We tested and discussed the synthesis of ionic liquids of variousphysical properties, including the glass transition temperature, opticalrotation value, density, viscosity, thermodynamic stability, andsolubility. Which, the state of the ionic liquid glass transitiontemperature is between-42--21℃; viscosity of0.77-30.2×103CP; thermaldecomposition temperature of between87-143℃. All of the ionic liquids aresoluble in polar organic solvent and not soluble in petroleum ether andhexane. In addition, we also studied such ionic liquid-catalyzed asymmetric Michael addition reaction, but did not get the desired results.(4) The first attempt to use the amino acids to prepare16kinds of sub-typeionic liquids and simply studied its melting point, optical activity andthermodynamic stability.Since the Proline cheap and chiral pyrrolidine structure of it showedgood stereoselectivity in the asymmetric Michael addition and the Aldolreaction, various types of small organic molecules catalyst synthesized byproline become hot spots in the asymmetric catalytic study. In this paper,we synthesized a new Prolinamide chiral catalyst containing guanidine, andstudied the catalytic asymmetric Aldol reaction (cyclohexanone andnitrobenzaldehyde), and got satisfactory results (ee:84%, yield:92dr:90:10).
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