近日，武汉科技大学庞青青团队实现了通过配位键重排的大环介导的三维到二维结构转变。相关论文于2025年7月21日发表在《中国化学》杂志上。

金属的结构转变有机框架（MOFs）涉及配位键的重大重排，是构建具有不同功能的新结构的有力策略。虽然这种转化通常是由溶剂、离子或热刺激驱动的，但功能性大环引发框架重构的潜力仍未被探索。

研究组首次揭示了大循环介导的MOF降维，其中引入葫芦b[6] （CB[6]）通过溶解-再结晶机制诱导3d到2d结构转变。这种转变涉及到配位键的断裂和重组，并通过多次外表面相互作用将CB[6]纳入框架。所得到的二维层状框架（CB[6]@Zn-TCA-L）在水溶液中表现出更强的稳定性，这归功于CB[6]大环的有序排列，并在其空腔中包裹了Me₂NH₂⁺阳离子。

此外，CB[6]@Zn-TCA-L的二维层状结构具有可接近的Lewis酸性金属位和CB[6]表面丰富的活性位点，这使得CB[6]@Zn-TCA-L在温和的条件下作为一种高效的催化剂，与各种环氧化物进行CO₂的环加成反应。

附：英文原文

Title: Macrocycle-Mediated 3D-to-2D Structural Transformation of a Metal−Organic Framework through Coordination Bond Rearrangement

Author: Wencai Li, Yinghao Xu, Simin Liu, Qingqing Pang

Issue&Volume: 2025-07-21

Abstract: Structural transformation of metalorganic frameworks (MOFs) involving significant rearrangement of coordination bonds represents a powerful strategy to construct novel structures with distinct functionalities. While such transformations are typically driven by solvent, ion, or heat stimuli, the potential of functional macrocycles to trigger framework reconstruction remains unexplored. Herein, we disclose the first macrocycle-mediated dimensional reduction of a MOF, where the introduction of cucurbit[6]uril (CB[6]) induces 3D-to-2D structural transformation through a dissolution-recrystallization mechanism. This transformation involves the breakage and reformation of coordination bonds and the incorporation of CB[6] within the framework through multiple outer-surface interactions. The resultant 2D layered framework (CB[6]@Zn-TCA-L) demonstrates enhanced stability in aqueous solutions, attributed to the ordered arrangement of CB[6] macrocycles with the encapsulation of Me2NH2+ cations in their cavities. Furthermore, the combination of its 2D layered structure featuring accessible Lewis acidic metal sites and abundant active sites on the CB[6] surface enables CB[6]@Zn-TCA-L to function as a highly efficient catalyst for the cycloaddition of CO2 with various epoxides under mild conditions.

DOI: 10.1002/cjoc.70177

Source: https://onlinelibrary.wiley.com/doi/10.1002/cjoc.70177