Tailor‐Made Pd_nL_2n Metal‐Organic Cages through Covalent Post‐Synthetic Modification

Abstract

Post-synthetic modification (PSM) is an effective approach for the tailored functionalization of metalorganic architectures, but its generalizability remains challenging. Herein we report a general covalent PSM strategy to functionalize Pd n L 2n 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 Pd 12 L 24 in common solvents can be greatly improved. Interestingly, concentration-dependent circular dichroism and aggregation-induced emission are achieved with chiral binaphthol (BINOL)-and tetraphenylethylenemodified Pd 12 L 24 , respectively. Furthermore, Pd 12 L 24 can be introduced with two different functional groups (e.g., chiral BINOL and achiral pyrene) through a step-bystep PSM route to obtain chirality-induced circularly polarized luminescence. Moreover, similar results are readily observed with a smaller Pd 2 L 4 system.

Anthracene-Functionalized Metallacage with Fluorescence Response Behavior to Anions

“…28 Moreover, the attachment of chiral motifs onto ligands permits the construction of chiral cages, thus facilitating chiral recognition or chiral catalysis. 29 The fabrication of metallacages containing fluorescent motifs 30,31 imparts unique optical properties to the cages. Therefore, we envisioned a new type of fluorescent metallacage might be successfully constructed by using a ligand decorated with fluorescent motifs.…”

(Bio)Functionalisation of Metal–Organic Polyhedra by Using Click Chemistry

“…[1] As such, as in inorganic nanoparticles, most of its physicochemical properties (e. g. solubility, recognition, and assembly) rely on its surface chemistry. [2][3][4][5][6][7][8][9][10][11] For instance, on its outer surface this cuboctahedral MOP contains up to 84 potential sites that can be used to introduce new functionalities: 72 that stem from positions 4, 5, and 6 of the aromatic organic linkers, and 12 that belong to the axial metal sites.…”

Helical Cage Rotors Switched on by Brake Molecule with Variable Fluorescence and Circularly Polarized Luminescence

“…Fujita et al have constructed a homologous series of coordination molecular cages with different-sized cavities to selectively enclose one or two dye molecules, realizing the accuracy control of monomeric, excimer, and charge-transfer luminescence in solution . Therefore, luminescent molecular cages would be suitable candidates for CPL materials while an appropriate chiral elements was rationally incorporated in them. ,− However, in comparison with ordinary small organic molecules or coordination supramolecular molecules, it is still a great challenge to effectively couple emissive and chiral elements in one cage-type molecule, and consequently, the study of CPL performance of molecular cages is still in its infancy.…”

“…So far, the explorations of CPL performance of molecular cages are mainly focused on the chirality induction using chiral species in the molecular states. ,− The CPL activity in the aggregation states seldom refers to cage molecules . Also, the manipulation of the CPL performance of cages by achiral factors is scarcely reported.…”