Switchable Divergent Synthesis of Inherently Chiral Calixarenes via Palladium-Catalyzed Asymmetric Hydroarylation of Alkynes

Inherently chiral calixarenes (ICCs) offer promise for enantioselective recognition, asymmetric catalysis, and optoelectronic materials, while their advancement remains hindered by synthetic limitations. Herein, we develop a regiodivergent protocol to access ICCs via Pd-catalyzed asymmetric intramolecular hydroarylation. Switchable 5-exo-dig and 6-endo-dig selectivities are achieved by simply tuning some catalytic parameters, affording an array of 3-methylene oxindole-embedded ICCs (up to 98% ee) and quinolinone-fused ICCs (up to 97% ee), respectively. Mechanistic studies uncover that 6-endo-cyclization occurs in a Friedel–Crafts-type arylation mode under dual Pd(II) π-acid and Brønsted acid catalysis, while 5-exo-cyclization is initiated by C−H activation, followed by migratory insertion under basic conditions. Critically, quinolinone-bearing ICCs exhibit photophysical and chiroptical properties, highlighting the utility of inherent chirality for chiral optoelectronics.