报告题目：Catalytic Enantioselective Redox-Neutral Reactions and Divergent Heterocycle Syntheses
The development of economical and selective catalytic processes is essential for the promotion of sustainable chemical synthesis. My research group at National University of Singapore focuses our efforts on the development of catalytic enantioselective redox-neutral transformations to access valuable chiral building blocks in organic synthesis. Such methods have the significant advantage of circumventing the redundant oxidation/reduction steps to reduce waste production in chemical synthesis. In particular, the stereo-convergent preparation of chiral amines and N-heterocycles from readily available racemic alcohols through borrowing hydrogen, and new processes of enantioselective isomerization of alkenyl alcohols will be discussed in details.
Another topic that will also be covered focuses on our recent discoveries of catalytic enantioselective medium-sized heterocycle synthesis. This new application of Pd-catalyzed allylic alkylation provides an efficient access to a range of 8 to 10-membered fused heterocycles using a flexible cycloaddition approach. Such unprecedented fused medium-sized heterocycles also demonstrate unique reactivities involving transannular bond formation and fragmentation.