Synthesis And Characterization Of Catalytic Functional Ionic Liquids

Ionic liquids?English for room temperature ionic liquids,abbreviated as RTILS?refer to the room temperature or near room temperature liquid composed of ions,also known as room temperature molten salt.Ionic liquids are widely used in many fields,such as electrochemistry,organic synthesis,catalysis,extraction,separation,polymerization and so on.The ionic liquids are widely used in electrochemistry,organic synthesis,catalysis,extraction and separation and other fields,is the hotspot of the concern of researchers in recent years.This thesis mainly main work is as follows:?1?synthesized by two kinds of imidazoles based ionic liquids.The first category is N,N '-dialkyl imidazole cation,Br^-?PF₆^-?BF₄^-,for preparation of anionic single imidazole cation liquid out of the nine.The second type is based on double imidazole cation,Br^-for preparation of anionic out of the three pairs of imidazole ionic liquids.?2?on the synthesis of 12 kinds of ionic liquid density,surface tension,as well as the physical properties such as viscosity,it is concluded that affect the quality of the density of the main and anionic radius of volume and the volume of the positive and negative ions,the surface tension mainly depends on the size of the electrostatic interaction between cation and anion,the size of the melting point and the size of the cation and anion,the symmetry,viscosity between the main cation and anion to the size of the van der Waals force and coulomb force.And using elemental analysis,IR,UV,and nuclear magnetic resonance?NMR?methods are analyzed.?3?examined the imidazole ionic liquids used in catalytic cycloaddition of carbon dioxide with propylene oxide.In the reaction conditions of 100?,reaction under 1.5 MPa 1 h,12 kinds of ionic liquid catalytic properties are obtained.The results showed that: when determining cationic [emim]⁺,the anion of Br^-,PF₆^-and BF₄^-get anion on the catalytic effect order PF₆^-<Br^-<BF₄^-.When determining anionic Br^-,cationic [emim]⁺,[bmim]⁺,[hmim]⁺cationic size order for the function of catalytic effect [emim]⁺<bmim]⁺<[hmim]⁺,it is concluded that the catalytic performance as cationic replace increases with the increase of alkyl chain,?3?when determining anion of Br^-double imidazole ionic liquids,thecationic[C₂?mim?₂]²⁺,[C₄?mim?₂]²⁺,[C₆?mim?₂]²⁺,cationic size order for the function of catalytic effect [C₂?mim?₂]²⁺<[C₄?mim?₂]²⁺<[C₆?mim?₂]²⁺,at the same time,through the above the catalytic reaction of double cation liquid catalytic performance is higher than single cation catalytic performance.The cycloaddition reaction conditions are optimized,and examines the different dosage of catalyst,temperature,pressure,reaction time on the catalytic reaction,the effect of catalytic reaction is given the best conditions,1,1'-dimethyl-3,3'-the hexyl base two imidazole two bromide catalyst is at 80?,1.5 MPa,without using any solvent reactions were the best for 60 min,the yield of product could reach 78%.At the end of this paper,the structure optimization and frequency calculation of four ionic liquids [bmim]Br,[bmim][BF4],[bmim][PF6]and C6?mim?2Br2 were carried out at the molecular and electronic levels.The atomic NBO charge distribution and molecular orbital quantum Chemical calculation.