Ion-Mediated Configuration Regulation and Chiralization in Cu(I) Cluster-Based Metallic Cages

Emulating the well-controlled conformational switching of biomacromolecules within artificial supramolecular assemblies remains a long-recognized challenge, especially exploring the synergy effects of metal clusters within metalloproteins. Herein, three types of copper cluster-based metallacages (helical Cu8-X, trigonal Cu12-Cl, and tetrahedral Cu16-SO4) were synthesized through a ligand isolation and anion-templated strategy, in which anion-dependent ligand arrangements and cluster distortions dictated configuration differences, while precise modulation of environmental anions could trigger structural transformations accompanied by significant luminescence modulation. Notably, Cu16SO4 exhibits a dual inner-outer binding mode: when using the highly negatively charged anion (SO42-) as a template, the four counterions are bound in the grooves near the four faces of the tetrahedron, significantly enhancing structural stability. Furthermore, anchoring chiral cations can effectively transfer chirality to the cage framework, endowing it with circularly polarized luminescence property. This work provides a novel strategy for the construction of cluster-based metallacages, and this integrated system of controllable synthesis, stimulus-responsive transformation, and tunable functionality provides inspiration for exploring the dynamic regulation mechanisms of biomolecules.