A Catenated Strut in a Catenated Metal-Organic Framework

摘要

The integration of mechanically interlocked molecules (MIMs) into metal-organic frameworks (MOFs) provides a way of coupling the workings and addressability of the former to the robustness and modularity of the latter. When MIMs are covalently linked to MOFs in such a well-defined fashion, the incoherent translational motion, which is observed in solution for the MIM progenitors, is eliminated. Although we have already shown that struts (2 nm in length) bearing components of MIMs, such as crown ethers, pseudorotaxanes, and catenanes, can be reticulated into open MOFs, when we attempted to build MOFs with three-dimensional structures incorporating catenane struts at this length scale, the only structure obtained was a two-dimensional one. Herein, we report the synthesis of a strut of exceptional length (3.3 nm) and describe its assembly into a three-dimensional MOF structure with vast openness, allowing bulky MIMs to be anchored at precise locations and with uniform relative orientations throughout the framework as a whole.