Preparation Of Amino Acid Ionic Liquids And Their Applications For The Synthesis Of Cyclic Carbonates

Carbon dioxide is the main greenhouse gas,but CO₂ is also an important C1 resources,with a wide range of recyclable,non-toxic,cheap and other advantages.The synthesis of cyclic carbonates is an important way to use CO₂ efficiently,and has received a lot of attention in recent years.Cyclic carbonates can be used in many fields such as industrial raw materials,anionic polar solvents,lithium secondary battery electrolytes,synthetic polycarbonate monomers,pharmaceutical and fine chemical industry intermediates.However,there are many problems such as the lack of catalytic activity,the need for solvent or cocatalyst,the difficulty of separation and the harsh reaction conditions.Therefore,the use of amino acid ionic liquid in the field of synthesis of cyclic carbonate,and trying to develop an economic,green synthetic route.The research is as follows:The amino acid ionic liquids of 1-butyl-3-methylimidazolium aspartic acid[Bmim][ASP],1-butyl-3-methylimidazolium glutamic acid [Bmim][Glu],N-octyl-N-methylmorpholinium glutamic acid [mor1,8][Glu] and N-hexylisoquinolinium aspartic acid [HiQuin][ASP] have been synthesized.The synthesized ILs were characterized by NMR and IR.The corresponding cyclic carbonate was synthesized by using amino acid ionic liquid as catalyst.Under the optimum reaction conditions?130 ?,0.5 MPa,12 h?,the yield of cyclic carbonate was above 96% and the selectivity was 99%.In the present study,the dual amino-functionalised amino acid ionic liquids of1-?3-aminopropyl?-3-butylimidazolium glutamic acid [APbim][Glu],1-?3-aminopropyl?-3-butylimidazolium Glycine [APbim][Gly] have been synthesized.The synthesized ILs were characterized by NMR and IR.The corresponding cyclic carbonate was synthesized by using dual amino-functionalised amino acid ionic liquids as catalyst.Under the optimum reaction conditions?105 ?,0.5 MPa,13 h?,the yield of the cyclic carbonate was above 93% and the selectivity was 99%.A series of amino acid ILs were synthesized in this paper have good yield and selectivity.They are used in the synthesis of cyclic carbonates of CO₂ and epoxide without the need for additional organic solvents and halogen-free,which can be recycled for several times.It has broad prospects in industrial application.