Abstract:

Seamless interactions between chirality of catalyst and prochirality of substrate are essential to transmission of asymmetry. Spatial separation of a prostereogenic element from either the reaction sites or the differential substitutions that reveal prochirality presents a universal hurdle in asymmetric catalysis. In this talk, I will describe an enantioselective, catalytic transformation where both the enantiotopic reaction sites and the prochirality-revealing groups are distant from the prostereogenic element. My research group has overcome the hurdles arising from the twofold spatial separations by innovating a unique class of ionic chiral catalysts and developing a general strategy employing distal electrostatic substrate–catalyst interactions. Contrary to general expectation, it is viable to achieve precise long-range enantioinduction by engaging electrostatic interactions at a remote position. Importantly, the ionic stereocontrol strategy is broadly applicable to construction of quaternary stereocenters, axially chiral biaryls, and mechanically planar chiral rotaxanes—all in settings that would be difficult to achieve through other methods.

Short Biography of the Speaker:

Ye Zhu received his B.Sc. degree from Peking University in 2006, and Ph.D. from The University of Chicago in 2012. His thesis work, with Professor Viresh Rawal, focused on squaramide-catalyzed phospha-Michael addition and Pd-catalyzed indole functionalization reactions. He then moved to the Massachusetts Institute of Technology to pursue postdoctoral studies with Professor Stephen Buchwald, where he worked on ligand-controlled asymmetric arylation of alpha-amino anions. In 2014, Ye joined the chemical process group at Bristol-Myers Squibb. He was a member of the team that developed P(V) reagents for oligonucleotide synthesis, which was awarded Horizon Prize—Robert Robinson Award in Synthetic Organic Chemistry by the Royal Society of Chemistry. In 2018, Ye started his independent academic career in the National University of Singapore. His current research interests lie in developing ionic metal catalysts to control site- and stereoselectivity.