Title：Asymmetric Transformation of Activated Methylidene Derivatives

Speaker：Dr.Huang Chongxing(Assistant Professor,The University of Hong Kong)

Time：Friday,May 16,2025,15:30–16:30

Inviter：Professor Zhu Chuanle

Venue：Room 401 of the Shaw Engineering Building

Organizing Unit：School of Chemistry and Chemical Engineering/Guangdong Provincial Key Laboratory of Functional Molecular Engineering

Speaker Profile:

Dr.Huang Chongxing obtained his Bachelor's degree from Peking University in 2012,under the guidance of Professors Wang Jianbo and Zhang Yan.He subsequently pursued his studies at the University of Texas at Austin and the University of Chicago,where he completed his Ph.D.in 2017 under the supervision of Professor Guangbin Dong. From 2017 to 2019,he conducted postdoctoral research in the group of Professor Barry M.Trost at Stanford University.In 2019,Dr.Huang joined the Department of Chemistry at The University of Hong Kong as an Assistant Professor and doctoral supervisor.His primary research focus is on the asymmetric transformation of activated methylidene derivatives.

Abstract:

Activated methyl compounds are a class of readily available molecules that can be rapidly derivatized to yield complex structures.In particular,di-substituted activated methylidene derivatives can be asymmetrically transformed to quickly generate high-value tetrasubstituted chiral centers.This presentation will focus on a series of tetradentate ligands derived from proline or piperidine methanol that can accommodate two zinc centers or a single magnesium atom to catalyze the desymmetrization reactions of malonates and 1,3-diketones.Specifically,through the desymmetrization of di-substituted malonates via hydrosilane reduction,we have achieved the stereoselective synthesis of various highly chiral pure synthetic building blocks,including all-carbon quaternary chiral centers,tertiary alkyl halides,α-tertiary amines,and tertiary alcohols.Based on these desymmetrized products,we have also designed some novel and rapid methods for synthesizing bioactive molecules and natural products.Additionally,using the same ligand framework,we can perform magnesium-catalyzed desymmetrization of ring-opening 1,3-diketones to achieve vicinal tetrasubstituted carbons.The chiral cyanohydrin products containing multiple functional groups can also be rapidly derivatized into more complex molecules,especially those with contiguous chiral centers.