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.

A pair of chiral metal−organic frameworks based on enantiomers of chiral Zn(salen) ligands have been successfully obtained by solvothermal subcomponent self-assembly. Both chiral MOFs were characterized by Infrared spectroscopy, UV–vis...

To develop a simple and general method for improving the circularly polarized luminescence (CPL) performances of materials is of great significance. In this work, two pairs of CPL-active homochiral metal-organic frameworks (MOFs) P/M-Et and P/M-Et(Cd) with eta topology are reported. In comparison to the reported isomorphic Zn-imidazolate MOFs P-Me and M-Me, both luminescence dissymmetry factor (g lum ) and photoluminescence quantum yields (𝚽 PL ) of P-Et and M-Et are largely improved by simply changing the methyl group to an ethyl group of ligands in P-Et and M-Et. Furthermore, the |g lum | values are significantly amplified up to 0.015 from 0.0057 by introducing the non-luminescent halogenated aromatics, while an enhanced fluorescence efficiency is observed simultaneously (from 27.2% to 47.3%). The figure of merit value is about 40 times larger than that of P-Me and M-Me. Similarly, the CPL performances of P/M-Et(Cd) are improved by about five times after encapsulating fluorobenzene molecules. This work represents a new and simple method for developing CPL-active MOF materials.

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