Linear aromatic amide foldamer-derived supramolecular architectures and materials

Abstract

Intramolecular hydrogen bonding in oligomeric aromatic amides may induce the backbones to adopt folded, zigzag, or other extended conformations, depending on the positions of the amide units and the hydrogen-bonding sites on the aromatic rings. This article summarizes our efforts in exploring the applications of this family of preorganized oligomers in supramolecular and materials chemistry. Several series of preorganized frameworks or foldamers have been developed as efficient acyclic receptors for binding both neutral and ionic guests. The backbones have been modified with discrete functional groups from the ends or the side chains. The resulting molecules have been applied for designing new molecular tweezers, assembling ordered supramolecular architectures (organogels and vesicles), and directing the formation of complicated macrocyclic and capsular systems. When the hydrogen-bonded folded segments are connected to n-butyl methacrylate copolymers as cross-links, the resulting copolymers display unique reversible mechanical properties owing to the breaking and recovering of the intramolecular hydrogen bonds. When the folded segments are incorporated into the dumbbell components of the donor–acceptor interaction-based pseudo[2]rotaxanes and [2]rotaxanes, they are capable of tuning the slippage/deslippage and switching of the ring component between the discrete “stations” in their dumbbell component.