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Alkali-Cation-Selective Arylation Promoted by Ion Recognition of Foldamers
Chenhao Yao1, Zhaocheng Xu1, Jun Tian1
1State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China.
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.
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