Chirality‐Induced Split Personality in Polymer with Intrinsic Microporosity‐Based Artificial Ion Channels

The construction of artificial transmembrane ion channels using polymers has emerged as a promising research avenue in membrane transport. In this study, we have designed and synthesized an intriguing class of intrinsically microporous chiral polyimides (PIM-PIs) employing trans/cis-1,2-diaminocyclohexanes (DACH) as structural building blocks. Remarkably, these chiral PIM-PIs exhibit distinct configurations, leading to contrasting ion transport properties. The cis-DACH-derived chiral polymer 1 demonstrates the hitherto highest Li+ transport activity (>100 pS), along with exceptionally high selectivity ratios for Li+/Na+ (17.1) and Li+/K+ (21.8). In contrast, chiral polymers 2a and 2b, synthesized from (1R,2R)-DACH and (1S,2S)-DACH, respectively, showcase pronounced anion transport capabilities and a remarkably high Cl-/K+ selectivity ratio of 17.6. This work introduces a multifunctional, chiral PIM-based artificial ion channel system with a "split personality" governed by its chiral constituents. It represents the first application of chiral polymers in transmembrane transport, inspiring innovative design strategies for developing polymer-based artificial ion channels.