The Application Of Chiral Semi-Aza-Crown Ether Ligand In The Catalytic Asymmetric Michael Addition Reaction Of 4-Hydroxy-6-methyl-2-pyrone

4-Hydroxy-6-methyl-2-pyrone, as a six-member ring lactone compound, is commonly used as an important donor in asymmetric Michael addition reactions. It is widely used in the synthesis of chiral pyrone compounds with good biological activities and medicinal value, especially in anti-hiv, anti-cancer and anaesthesia, etc.Additionally, semi-aza-crown ether is an important class of chiral ligands for the asymmetric catalysis.This thesis mainly discussed the synthesis of a series of chiral semi-aza-crown ether ligand, and their application in the catalysis of asymmetric Michael addition reactions with 6-methyl-4-hydroxy-2-pyrone and β,γ-unsaturated-α- ketoesters.Based on the screen of the ligand types, solvent, temperature, additives, the optimal reaction conditions for the asymmetric Michael addition reactions was received. With anhydrous dichloromethane as solvent, 10 mol % of chiral ligand L8 and 20 mol % Zn Et2 as catalysts, 15 hours reaction time under 0 ℃, the reaction yield and ee value were obtained as 86% and 84%, respectively. We further studied the scope of application for the substrate β,γ-unsaturated-α- ketoesters under the optimal reaction conditions. In the end, the possible reaction mechanism was proposed.