Alkali-Cation-Selective Arylation Promoted by Ion Recognition of Foldamers

Abstract

To explore alkali-cation selectivity at the chemical reaction level, in this work, we for the first time focused on the different behaviors of potassium and sodium ions in intra- and intermolecular arylation. We prepared a series of aromatic foldamers based on pyridine/oxadiazole alternating sequences as the catalysts for the arylation. Our studies revealed that foldamers can selectively recognize K⁺ over Na⁺ and the interactions between foldamers and K⁺ drive the arylation with a significant yield. In contrast, no trace of the product can be found with Na⁺. Furthermore, foldamers, with biased handedness, can afford products with optical activity. The balance between two enantiomers of products can be freely controlled by the different conformations of foldamers.