Wang Yiliang, Liu Taotao, Zhang Yang-Yang, Li Bin, Tan Liting, Li Chunju, Shen Xing-Can, Li Jun
State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin, 541004, PR China.
Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518005, PR China.
Nat Commun. 2024 Feb 14;15(1):1363. doi: 10.1038/s41467-024-45681-6.
The study of cross-catenated metallacages, which are complex self-assembly systems arising from multiple supramolecular interactions and hierarchical assembly processes, is currently lacking but could provide facile insights into achieving more precise control over low-symmetry/high-complexity hierarchical assembly systems. Here, we report a cross-catenane formed between two position-isomeric Pt(II) metallacages in the solid state. These two metallacages formed [2]catenanes in solution, whereas a 1:1 mixture selectively formed a cross-catenane in crystals. Varied temperature nuclear magnetic resonance experiments and time-of-flight mass spectra are employed to characterize the cross-catenation in solutions, and the dynamic library of [2]catenanes are shown. Additionally, we searched for the global-minimum structures of three [2]catenanes and re-optimized the low-lying structures using density functional theory calculations. Our results suggest that the binding energy of cross-catenanes is significantly larger than that of self-catenanes within the dynamic library, and the selectivity in crystallization of cross-catenanes is thermodynamic. This study presents a cross-catenated assembly from different metallacages, which may provide a facile insight for the development of low-symmetry/high-complexity self-assemble systems.
交叉连环金属笼的研究目前尚属空白，这类金属笼是由多种超分子相互作用和分级组装过程产生的复杂自组装体系，但它可能为实现对低对称性/高复杂性分级组装体系的更精确控制提供便捷的见解。在此，我们报道了两种位置异构的Pt(II)金属笼在固态下形成的交叉连环烷。这两种金属笼在溶液中形成了[2]连环烷，而1:1的混合物在晶体中选择性地形成了交叉连环烷。采用变温核磁共振实验和飞行时间质谱对溶液中的交叉连环化进行了表征，并展示了[2]连环烷的动态库。此外，我们搜索了三种[2]连环烷的全局最小结构，并使用密度泛函理论计算对低能结构进行了重新优化。我们的结果表明，在动态库中，交叉连环烷的结合能明显大于自连环烷，交叉连环烷结晶的选择性是热力学性质的。这项研究展示了一种由不同金属笼构成的交叉连环组装，这可能为低对称性/高复杂性自组装体系的发展提供便捷的见解。
