Chiral Cages With Asymmetric π‐Clefts Enable Catalytic Enantioconvergent S _N 1 Transformation via Synergistic Cation–π and Anion–π Interactions

ABSTRACT Understanding and exploiting noncovalent interactions are essential for advancing chemical transformations and catalysis. While both cation–π and anion–π interactions have attracted growing attention, their deliberate use as a dominant design element remains elusive. Here, we present an ion–π catalysis strategy employing both π interactions as the key driving force to steer challenging stereoselective carbocation transformation, enabling catalytic enantioconvergent S N 1 reactions. Through straightforward one‐pot synthesis, we efficiently constructed a series of chiral cages composed solely of aromatic units, featuring electron‐rich asymmetric π clefts and electron‐deficient π exterior surfaces. This all‐π system leverages strong cation–π interactions to trap and stabilize carbocation intermediates within its chiral V‐cleft, while simultaneously engaging the counteranion via anion–π interactions on its exterior surface. This synergistic π network drives a highly enantioconvergent S N 1 process, enabling asymmetric allylation of propargyl acetates to form congested quaternary stereocenters. This system shows considerable sensitivity to subtle electronic and steric changes, resembling enzymatic behavior. This work provides a strategic approach for harnessing noncovalent π interactions to address challenging transformations.