Abstract
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.