Savastano Matteo, Bazzicalupi Carla, Bianchi Antonio
Dept. of Chemistry "Ugo Schiff", University of Florence, via della Lastruccia 3-13, 50019, Sesto Fiorentino, Italy.
Chemistry. 2020 May 12;26(27):5994-6005. doi: 10.1002/chem.202000505. Epub 2020 Apr 17.
XOFs-type materials (X=M, C, S, that is, metal-organic frameworks, covalent organic frameworks and supramolecular organic frameworks, respectively) share a common unifying feature: mutual spatial orientation of constituting components is strictly directional and unchanging by design. Herein, we illustrate an alternate design for porous architectures, as rigid joints constituted by coordinative (MOFs), covalent (COFs), or hydrogen-donor/acceptor (SOFs) bonds, are replaced by supramolecular ball joints, which confer unprecedented flexibility, especially angular, to porous networks. The obtained frameworks remain highly organized but are also permutable: lacking a forced convergence towards an immutable minimum energy structure, these systems remain able to adjust depending on external conditions. Results of POF (permutable organized framework) synthesis is a family of structures rather than a single pre-determined three-dimensional arrangement, as we demonstrate with an illustrative set of 5 XRD structures.
XOFs 型材料（X = M、C、S，即分别为金属有机框架、共价有机框架和超分子有机框架）具有一个共同的统一特征：构成组件的相互空间取向在设计上严格定向且不变。在此，我们阐述了一种多孔结构的替代设计，即由配位（MOFs）、共价（COFs）或氢供体/受体（SOFs）键构成的刚性节点被超分子球关节所取代，这赋予了多孔网络前所未有的灵活性，尤其是角度方面的灵活性。所得到的框架仍然高度有序，但也具有可置换性：由于缺乏朝着不可变的最低能量结构的强制收敛，这些系统能够根据外部条件进行调整。POF（可置换有序框架）合成的结果是一族结构，而非单一的预定三维排列，正如我们通过一组 5 个 XRD 结构所展示的那样。
