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Post‐synthetic modification plays a crucial role in precisely adjusting the structure and functions of advanced materials. Herein, we report the self‐assembly of a tubular heterometallic Pd3Cu6L16 capsule that incorporates Pd(II) and CuL1 metalloligands. This capsule undergoes further modification with two tridentate anionic ligands (L2) to afford a bicapped Pd3Cu6L16L22 capsule with an Edshammer polyhedral structure. By employing transition metal ions, acid, and oxidation agents, the bicapped capsule can be converted into an uncapped one. This uncapped form can then revert back to the bicapped structure on the addition of Br− ions and a base. Interestingly, introducing Ag+ ions leads to the removal of one L2 ligand from the bicapped capsule, yielding a mono‐capped Pd3Cu6L16L2 structure. Furthermore, the size of the anions critically influences the precise control over the post‐synthetic modifications of the capsules. It was demonstrated that these capsules selectively encapsulate tetrahedral anions, offering a novel approach for the design of intelligent molecular delivery systems. [ABSTRACT FROM AUTHOR]

Metal‐organic cages (MOCs) are supramolecular coordination complexes that have internal cavities for hosting guest molecules and exhibiting various properties. However, the functions of MOCs are limited by the choice of the building blocks. Post‐synthetic modification (PSM) is a technique that can introduce new functional groups and replace existing ones on the MOCs without changing their geometry. Among many PSM methods, covalent PSM is a promising approach to modify MOCs with tailored structures and functions. Covalent PSM can be applied to either the internal cavity or the external surface of the MOCs, depending on the functionality expected to be customized. However, there are still some challenges and limitations in the field of covalent PSM of MOCs, such as the balance between the stability of MOCs and the harshness of organic reactions involved in covalent PSMs. This concept article introduces the organic reaction types involved in covalent PSM of MOCs, their new applications after modification, and summarizes and provides an outlook of this research field. [ABSTRACT FROM AUTHOR]

Post‐synthetic modification (PSM) is an effective approach for the tailored functionalization of metal‐organic architectures, but its generalizability remains challenging. Herein we report a general covalent PSM strategy to functionalize PdnL2n metal‐organic cages (MOCs, n=2, 12) through an efficient Diels–Alder cycloaddition between peripheral anthracene substituents and various functional motifs bearing a maleimide group. As expected, the solubility of functionalized Pd12L24 in common solvents can be greatly improved. Interestingly, concentration‐dependent circular dichroism and aggregation‐induced emission are achieved with chiral binaphthol (BINOL)‐ and tetraphenylethylene‐modified Pd12L24, respectively. Furthermore, Pd12L24 can be introduced with two different functional groups (e.g. chiral BINOL and achiral pyrene) through a step‐by‐step PSM route to obtain chirality‐induced circularly polarized luminescence. Moreover, similar results are readily observed with a smaller Pd2L4 system. [ABSTRACT FROM AUTHOR]

A variety of planar organic fluorophores (R=phenyl, naphthalenyl, pyrenyl) and luminescence promotors (X=Cl, Br, I) were equipped, respectively, on the alternatively arranged vertices of cubic ZnII‐imidazolate cages through orthogonal subcomponent self‐assembly. It was found that supramolecular interactions, especially weak C−H⋅⋅⋅X interactions, play a key role in activating an efficient radiative pathway, coupled with reduced nonradiative decay rate through metal coordination, therefore significantly boosting the emission quantum yields of the system. This finding provides a strategy that utilizes molecular geometry and supramolecular interactions to modulate the emission efficiency of luminescent cage‐based materials. [ABSTRACT FROM AUTHOR]

Biological function arises by the assembly of individual biomolecular modules into large aggregations or highly complex architectures. A similar strategy is adopted in supramolecular chemistry to assemble complex and highly ordered structures with advanced functions from simple components. Here we report a series of diamond-like supramolecular frameworks featuring mesoporous cavities, which are assembled from metal-imidazolate coordination cages and various anions. Small components (metal ions, amines, aldehydes, and anions) are assembled into the hierarchical complex structures through multiple interactions including covalent bonds, dative bonds, and weak CH⋅⋅⋅X (X=O, F, and π) hydrogen bonds. The mesoporous cavities are large enough to trap organic dye molecules, coordination cages, and vitamin B12. The study is expected to inspire new types of crystalline supramolecular framework materials based on coordination motifs and inorganic ions. [ABSTRACT FROM AUTHOR]

A supramolecular dual emissive system incorporating two classical copper(i)-cluster-based luminophores, namely, Cu4I4and Cu3Pz3(Pz = pyrazolate), is reported. The targeted luminescent coordination polymer exhibits reversible thermochromism spanning from green to orange-red. [ABSTRACT FROM AUTHOR]

[Display omitted] • The edge- and face-directed self-assembly strategies of IMOCs were summarized. • The abundant coordination modes in IMOCs were firstly proposed. • IMOCs with different topologic structures were detailed introduced and analyzed. • Advanced applications of IMOCs were systematacially presented and discussed. The coordination-driven self-assembly provides a favourable methodology for constructing metal–organic architectures with diverse structures and functions. As a classical five-membered heterocyclic ligand, imidazole is widely used in the construction of metal–organic materials with finitely and infinitely structures. In this review, the synthetic methods of imidazole-based metal–organic cages (IMOCs) are introduced and analysed. Subsequently, various type of IMOCs with structure and coordination diversity of imidazole and its polytopic derivatives, including tetrahedron, cube, octahedron, rhombic dodecahedron, tetartoid, bicapped square antiprism, prism, etc., have been rationally categorised by using edge- and face-directed self-assembly strategies. Moreover, the functional applications of these IMOCs, including host–guest chemistry, luminescence, magnetism, catalysis, biological effect, and proton conductivity, are also comprehensively summarized. The relationship between structures and properties of IMOCs are elucidated and concluded, which provides some inspiration for designing new metal–organic cages with advanced functions. [ABSTRACT FROM AUTHOR]