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Crystalline porous frameworks, such as covalent organic frameworks (COFs), metal–organic frameworks (MOFs), and hydrogen-bonded organic frameworks (HOFs), have demonstrated exceptional potential in diverse applications, including gas adsorption/separation, catalysis, sensing, electronic devices, etc. However, the building blocks for constructing ordered frameworks are typically limited to multisubstituted aromatic small molecules, and uncontrolled interpenetration has remained a long-standing challenge in the field. Shape-persistent macrocycles and molecular cages have garnered significant attention in supramolecular chemistry and materials science due to their unique structures and novel properties. Using such preporous shape-persistent 2D macrocycles or 3D cages as building blocks to construct extended networks is particularly appealing. This macrocycle-to-framework/cage-to-framework hierarchical assembly approach not only mitigates the issue of interpenetration but also enables the integration of diverse properties in an emergent fashion. Since our demonstration of the first organic cage framework (OCF) in 2011 and the first macrocycle-based ionic COFs (ICOFs) in 2015, substantial advancements have been made over the past decade. In this Account, we will summarize our contributions to the development of crystalline porous frameworks, consisting of shape-persistent macrocycles and molecular cages as preporous building blocks, via hierarchical dynamic covalent assembly. We will begin by reviewing representative design strategies and the synthesis of shape-persistent macrocycles and molecular cages from small molecule-based primary building blocks, emphasizing the critical role of dynamic covalent chemistry (DCvC). Next, we will discuss the further assembly of preporous macrocycle/cage-based secondary building blocks into extended frameworks, followed by an overview of their properties and applications. Finally, we will highlight the current challenges and future directions for this hierarchical assembly approach in the synthesis of crystalline porous frameworks. This Account offers valuable insights into the design and synthesis of functional porous frameworks, contributing to the advancement of this important field. 

Abstract Within the past two decades, covalent adaptable networks (CANs) have emerged as a novel class of dynamically crosslinked polymers, combining the benefits of thermosets and thermoplastics. Although some CANs with charged side chains have been reported, CANs with negatively charged backbones remain very limited. The integration of permanent charge into the backbones upon their formation could open up important new applications. Here, we introduce a series of aliphatic spiroborate‐linked ionic covalent adaptable networks (ICANs), representing a new category of dynamic ionomer thermosets. These ICANs were synthesized using a catalyst‐free, scalable, and environment‐friendly method. Incorporating lithium or sodium as counter cations in these networks yielded promising ion conductivity without the need of plasticizers. The dynamic nature of the spiroborate linkages in these materials allows for rapid reprocessing and recycling under moderate conditions. Furthermore, their potential as flexible solid‐state electrolytes is demonstrated in a device that maintained robust conducting performance under extreme physical deformation, coupled with effective self‐healing properties. This research opens new possibilities for future development of dynamic ionomer thermosets and their potential applications in flexible electronic devices.