Preorganized Aryltriazole Foldamers as Effective Transmembrane Transporters for Chloride Anion

Preorganized aryltriazole foldamers 1 and 2 were designed and synthesized. NMR studies and X-ray analysis demonstrate that 1 adopts a crescent conformation driven by a series of continuous hydrogen bonds at the periphery of the foldamer, whereas 2 displays a coil conformation. NMR titrations reveal that the affinities of fully preorganized foldamer 1 for halogen anions are much stronger that those of partially preorganized foldamer 2. Furthermore, it is found that such full preorganization makes 1 an effective transmembrane transporter for the chloride anion across a lipid bilayer.