Gao Zhao, Xie Xuxu, Zhang Juan, Yuan Wei, Yan Hongxia, Tian Wei
School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, 710072, China.
Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore.
Nat Commun. 2024 Dec 30;15(1):10762. doi: 10.1038/s41467-024-55106-z.
Metastable supramolecular polymerization under kinetic control has recently been recognized as a closer way to biosystem than thermodynamic process. While impressive works on metastable supramolecular systems have been reported, the library of available non-covalent driving modes is still small and a simple yet versatile solution is highly desirable to design for easily regulating the energy landscapes of metastable aggregation. Herein, we propose a coopetition-driven metastability strategy for parallel/perpendicular aromatic stacking to construct metastable supramolecular polymers derived from a class of simple monomers consisting of lateral indoles and aromatic core. By subtly increasing the stacking strength of aromatic cores from phenyl to anthryl, the parallel face-to-face stacked aggregates are competitively formed as metastable products, which spontaneously transform into thermodynamically favorable species through the cooperativity of perpendicular edge-to-face stacking and parallel offset stacking. The slow kinetic-to-thermodynamic transformation could be accelerated by adding seeds for realizing the desired living supramolecular polymerization. Besides, this transformation of parallel/perpendicular aromatic stacking accompanied by time-dependent emission change from red to yellow is employed to dynamic cell imaging, largely avoiding the background interferences. The coopetition relationship of different aromatic stacking for metastable supramolecular systems is expected to serve as an effective strategy towards pathway-controlled functional materials.
动力学控制下的亚稳态超分子聚合最近被认为是一种比热力学过程更接近生物系统的方式。虽然已经报道了关于亚稳态超分子系统的令人印象深刻的工作，但可用的非共价驱动模式库仍然很小，因此非常需要一种简单而通用的解决方案来设计用于轻松调节亚稳态聚集的能量景观。在此，我们提出了一种用于平行/垂直芳环堆积的竞争驱动亚稳性策略，以构建由一类由侧向吲哚和芳环核心组成的简单单体衍生的亚稳态超分子聚合物。通过巧妙地将芳环核心的堆积强度从苯基增加到蒽基，平行面对面堆积的聚集体作为亚稳态产物竞争性形成，其通过垂直边对面堆积和平行错位堆积的协同作用自发地转变为热力学上有利的物种。通过添加种子可以加速缓慢的动力学到热力学转变，以实现所需的活性超分子聚合。此外，这种平行/垂直芳环堆积的转变伴随着从红色到黄色的时间依赖性发射变化被用于动态细胞成像，很大程度上避免了背景干扰。不同芳环堆积对亚稳态超分子系统的竞争关系有望成为制备路径可控功能材料的有效策略。
