Isolation of the Secondary\nBuilding Unit of a 3D Metal–Organic\nFramework through Clip-Off Chemistry, and Its Reuse To Synthesize\nNew Frameworks by Dynamic Covalent Chemistry

Herein, we present a novel methodology for synthesizing\nmetal clusters\nor secondary building units (SBUs) that are subsequently employed\nto construct innovative metal–organic frameworks (MOFs) via\ndynamic covalent chemistry. Our approach entails extraction of SBUs\nfrom preformed MOFs through complete disassembly by clip-off chemistry.\nThe initial MOF precursor is designed to incorporate the desired SBU,\nconnected exclusively by cleavable linkers (in this study, with olefinic\nbonds). Cleavage of all the organic linkers (in this study, via ozonolysis\nunder reductive conditions) liberates the SBUs functionalized with\naldehyde groups. Once synthesized, these SBUs can be further reacted\nwith amines in dynamic covalent chemistry to build new, rationally\ndesigned MOFs.