Design And Synthesis Novel Lewis Acid-Lewis Base Bifunctional Catalysts Derived From BINOLs And Imidazoles And Their Applications In Asymmetric Catalysis

The design and development of new high-performance catalysts for applications in asymmetric catalysis is of ongoing interest in organic chemistry. The mechanism of action of many enzymes involves the cooperation of two or more reactive centres. It is considered that by imitating nature, the principle of multifunctional catalysis could offer many advantages over existing strategies. An effective enantioselective synthetic method based on a new concept of double catalytic activation has been developed, in which both electrophile and nucleophile precursors are activated by the use of catalytic amount of chiral Lewis acid and Lewis base, respectively. This method has been successfully applied to enantioselective synthesis. The synergistic activation by two or more reactive centers allows high reaction rates and excellent transfer of stereochemical information.In this thesis, we focused on the enantioselective alkynylzincs addition to aldehydes catalyzed by chiral Lewis acid-Lewis base bifunctional catalysts at ambient temperature, in order to extend the application of the BINOL / Ti(OiPr)₄ / Et₂Zn system to the reaction related with functional alkynes. We discovered that in the presence of N-methyl-imidazole (NMI), Et₂Zn, BINOL and Ti(OiPr)₄, various functional alkynes could add to a wide scope of aldehydes at room temperature in...