Origin of Enantioselectivity Reversal in Lewis Acid-Catalyzed Michael Additions Relying on the Same Chiral Source

Enantiodivergence is an important concept in asymmetric catalysis that enables access to both enantiomers of a product relying on the same chiral source. This strategy is particularly appealing as an alternate approach when only one enantiomer of the required chiral ligand is readily accessible but both enantiomers of the product are desired. Despite their potential significance, general catalytic methods to induce reversal in enantioselectivity remain underdeveloped. Herein we report our studies focused on elucidating the origin of enantioselectivity reversal in Lewis acid-catalyzed Michael additions relying on the same enantiomer of ligand as the chiral source. Our results provide a detailed mechanistic understanding of this transformation based on experimental and computational investigations which reveal the important interplay between kinetics and thermodynamics responsible for the observed enantiodivergence.