Constructing Ultrastable Metallo-Cages via In Situ Deprotonation/Oxidation of Dynamic Supramolecular Assemblies

Coordination-driven self-assembly enables the spontaneousconstructionof metallo-supramolecules with high precision, facilitated by dynamicand reversible metal-ligand interactions. The dynamic natureof coordination, however, results in structural lability in many metallo-supramolecularassembly systems. Consequently, it remains a formidable challengeto achieve self-assembly reversibility and structural stability simultaneouslyin metallo-supramolecular systems. To tackle this issue, herein, weincorporate an acid-/base-responsive tridentate ligand into multitopicbuilding blocks to precisely construct a series of metallo-supramolecularcages through coordination-driven self-assembly. These dynamic cagelikeassemblies can be transformed to their static states through mild in situ deprotonation/oxidation, leading to ultrastableskeletons that can withstand high temperatures, metal ion chelators,and strong acid/base conditions. This in situ transformationprovides a reliable and powerful approach to manipulate the kineticfeatures and stability of metallo-supramolecules and allows for modulationof encapsulation and release behaviors of metallo-cages when utilizingnanoscale quantum dots (QDs) as guest molecules.

Automated summary

Coordination-driven self-assembly allows for the spontaneous construction of highly precise metallo-supramolecules through dynamic and reversible metal-ligand interactions. However, the dynamic nature of coordination often leads to structural instability in many metallo-supramolecular assembly systems. In this study, an acid-/base-responsive tridentate ligand is incorporated into multitopic building blocks to achieve self-assembly reversibility and structural stability in metallo-supramolecular cages. The in situ transformation of these dynamic assemblies provides a reliable approach to manipulate the kinetic features and stability of metallo-supramolecules and enables modulation of encapsulation and release behaviors when utilizing nanoscale quantum dots (QDs) as guest molecules.