Topology Interlocking Drives the Construction and Application of Crystalline Porous Materials

Comprehensive Summary Mechanical interlocking has recently emerged as a novel structural design principle for crystalline porous organic materials. Unlike traditional reticular chemistry that relies on covalent or coordination bonding to build rigid lattices, mechanical bonding provides an alternative design space where the structural integrity of the crystal is maintained while the individual components preserve intrinsic mobility. The incorporation of interlocked macrocycles, cages, and framework subunits has enabled new forms of structural order that combine crystallinity with dynamic molecular motion. This review summarizes current progress in the synthesis and structural design of crystalline porous materials driven by topology interlocking. The discussion is organized by increasing structural hierarchy, covering interlocked macrocycles, interlocked cages, mechanically interlocked metal‐organic frameworks, and interlocked covalent organic frameworks. The relationships between interlocking geometry, structural organization, and application area are highlighted. The review concludes with an outlook on the opportunities and challenges associated with mechanical bonding as a programmable element in crystalline porous materials. Key Scientists A brief overview of the leading contributors in the field highlights how topology interlocking has become a powerful design principle for crystalline porous materials. Foundational insights were provided by Sauvage and Stoddart in the 1980s, whose studies on mechanically bonded molecules and molecular machines significantly promoted the development of mechanically interlocked molecules. Fujita advanced the field by showing that metal‐directed self‐assembly can spontaneously produce catenated metal‐organic cages (MOCs) and macrocycles, while Cooper demonstrated that catenated organic cages can arise through dynamic covalent chemistry without metal templates. Mechanical interlocking was extended to frameworks by Yaghi, who realized woven covalent organic frameworks (COFs), and by Loh, who introduced rotaxane‐based COFs with engineered interlayer behavior. Aida and Sato reported the first metal‐organic frameworks constructed from a catenated polymer backbone. Most recently, Cui and co‐workers first reported an interlocked metal peptide macrocycle and hetero‐interlocked MOC. Important contributions from Jin and Guido Clever expanded the scope of interlocked macrocycles and MOCs, respectively. Collectively, these achievements established the foundation of topology interlocked crystalline porous materials.