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Abstract: Controlling the self‐assembly of giant molecular building blocks into complex architectures with similar hierarchy to biological species remains a major challenge in supramolecular chemistry. Akin to protein structure, here we present the self‐assembly of giant molecular nanocapsules into supramolecular coordination polymers with controlled hierarchy from primary to secondary and tertiary structures. First, we successfully prepared discrete nanocapsules (secondary structures) consisting of multicomponents, such as organic macrocycles and metal‐based secondary building units (primary structures). Second, these nanocapsules can self‐organize into various 2D and 3D supramolecular coordination polymers (tertiary structures) through coordination‐driven assembly. The periphery 24 flexible alkyl chains and 24 metal ions available for potential coordination make these nanocapsules comparable to functionalized solid nanoparticles with non‐specific binding sites at the surface and allow the nanocapsules to self‐adjust their orientations and coordination modes to facilitate the self‐assembly process. This study sheds light on the self‐assembly of giant building units with complex molecular structures and opens up possibilities for the design of new hierarchical architectures with innovative properties and functions in many applications such as biomimics, biomedicine, and molecular devices. [ABSTRACT FROM AUTHOR]

Novel metal-organic nanocapsules have shown great potential in various applications ranging from drug delivery, sensing, gas adsorption/separation, and catalysis. Herein, we provide a brief introduction of pyrogallol[4]arene-based dimeric (M7L2 and M8L2) and hexameric (M12L6 and M24L6) metal-organic nanocapsules. In addition, hierarchical assemblies using dimeric/hexameric nanocapsules as building blocks are introduced. The strategies of direct linking, addition of a bridging linker, and dual function of C-propan-3-ol-pyrogallol[4]arene have been employed to connect these nanocapsules into supramolecular superstructures. In addition, the solution-phase studies of metallopyrogallol[4]arene complexes showing solution-phase stability, rearrangement of nanoassemblies, and magnetic behavior of these nanocapsules are presented. [ABSTRACT FROM AUTHOR]

Novel supramolecular nanocapsules based on metal-directed assembly have captured tremendous interest due to their applications in fields such as catalysis, selective gas adsorption, and biomedicine. Functionalization of metal-organic nanocapsules (MONCs) by using organic ligands with different pendant groups affords more complexity to the structure and may lead to novel properties. In this work, we report the solvothermal synthesis of a group of magnesium-based MONCs using C-alkylpyrogallol[4]arenes with varying alkyl chain lengths. The structures of these nanocapsules are characterized by single-crystal X-ray diffraction analysis. As expected, a progression in size of the nanocapsules is observed as the alkyl chain length increases. The effect of the chain length on the solubility of MONCs in water has been determined. This work shows the generality of the solvothermal approach for the synthesis of MONCs with different organic ligands and demonstrates that surface functionalization of MONCs may serve as an effective way to tailor their properties. The unique biocompatible nature and inherent large cavity of these magnesium-based MONCs make these nanocapsules promising for potential applications in biomedicine. [ABSTRACT FROM AUTHOR]

Considering the rapidly rising CO2 level, there is a constant need for versatile materials which can selectively adsorb CO2 at low cost. The quest for efficient sorptive materials is still on since the practical applications of conventional porous materials possess certain limitations. In that context, we designed, synthesized, and characterized two novel supramolecular organic frameworks based on C-pentylpyrogallol[4]arene (PgC5) with spacer molecules, such as 4,4′-bipyridine (bpy). Highly optimized and symmetric intermolecular hydrogen-bonding interactions between the main building blocks and comparatively weak van der Waals interactions between solvent molecules and PgC5 leads to the formation of robust extended frameworks, which withstand solvent evacuation from the crystal lattice. The evacuated framework shows excellent affinity for carbon dioxide over nitrogen and adsorbs ca. 3 wt % of CO2 at ambient temperature and pressure. [ABSTRACT FROM AUTHOR]