Inherently chiral resorcinarene cavitands through ionic catalyst-controlled cross-coupling
Mingfeng Li, Clement Kim Soon Ho, Ivan Keng Wee On, Vincent Gandon, Ye Zhu
Abstract
Cavitands have emerged as privileged architectures in supramolecular chemistry. Nonetheless, achieving structural diversity and tunability through heterofunctionalization along the rims of macrocycles has remained a formidable challenge. As a rudimental example, stepwise conversion of C 4v -symmetric scaffolds to inherently chiral ABCD patterns is synthetically impractical owing to the low theoretical yields (0.8%) and the need for chromatographic enantioseparation. Herein, we report a catalytic desymmetrization strategy to access inherently chiral cavitands. Through engineering ionic chiral palladium catalysts, diverse functionalities, including aryl, alkenyl, alkynyl, and amino groups, can be installed on the large rims with high site- and stereoselectivity. An adaptable stepwise protocol has been established to furnish designer ABCD-type cavitands in accordance with the choreography of coupling partners. Experimental and computational studies reveal synergistic electrostatic steering and electrostatic catalysis by the ionic catalyst–substrate interactions.