Synthesis Of Functional Ionic Liquids And Their Application In Basic Catalysis

Recently, with the development of ionic liquids, functional ionic liquids endowed with catalytically active groups have been attracted more and more attention due to their unique features, and have been successfully applied to catalyze a number of chemical transformations.This thesis is mainly about synthesis of functional ionic liquids and their application in basic catalysis. It involves three sections. The first section is about the synthesis of Lewis-Br(o|¨)nsted combined basic ionic liquids and their solvent effect in Knoevenagel condensation; the second section is about basic ionic liquid [Bmim]OAc catalyzed Michael addition of active methylene to conjugated ketones; the third section is about the synthesis of ionic liquid involving hydroxy and its application in Knoevenagel condensation.In the first section, Lewis-Br(o|¨)nsted combined basic ionic liquids are successfully synthesized. Their catalytic activity for the condensation of aldehydes/ketones with ethyl cyanoacetate was also investigated. The results show that these combined basic ionic liquids have very high activity for Knoevenagel condensation. Different aromatic aldehydes react with cyanoacetate to give the corresponding products in the yields of 85-99%. It is found that protonated solvents such as ethanol and glycol have higher activity than other solvents. The combined basic ionic liquids can be reused for 3 times without decrease of activity.In the second section, catalytic amount basic ionic liquid, [Bmim]OAc, was used as catalyst for the Michael addition reation of ethyl cyanoacetate withα,β-unsaturated compound. The results show that [Bmim]OAc has good catalytic ability to Michael addition under mild condition in short time. Different solvents are also used for comparison, DMSO gives the highest reactivity and the corresponding products are afforded in the yields of 71-97%.In the third section, ionic liquids 1-(2, 3-dihydroxy) propyl-3-methylimidazolium acetate and 1-(2, 3-dihydroxy) propyl-3-methylimidazolium hydroxide are synthesized by ion-exchange. These ionic liquids are used as catalyst in Knoevenagel reaction. The two ionic liquids show acid-base cooperitivity in the condensation of benaldehyde and ethyl cyanoacetate in ethyl alcohol. The coorperative effect probably attributes the activation of the carbonyl group of benzaldehyde by diol group in the acid-base bifunctional ionic liquid through double hydrogen bonding, while the OAc~- group was responsible for the deprotonation of ethyl cyanoacetate.