Solvent-Directed Supramolecular Reconstruction Through Coupled Coordination-Bond Dynamics and Covalent-Bond Formation

Abstract Understanding how external stimuli actively direct bond reorganization and supramolecular reconstruction remains a fundamental challenge in adaptive self-assembly. Although solvent-induced transformations are widely observed in supramolecular systems, the molecular mechanisms by which solvents simultaneously regulate coordination-bond dynamics and covalent-bond formation remain poorly understood. Herein, we report a rare cluster-based triply interlocked [2]catenane, [(Tp*WS3Cu3)8(L)12(OTf)8](OTf)8 ([1(OTf)8], Tp* = tris(3,5-dimethylpyrazolyl)borate; L = (Z)-4,4′-(but-1-en-3-yne-1,4-diyl)dipyridine; OTf– = trifluoromethanesulfonate), which undergoes methanol-directed supramolecular reconstruction into an octahedral cage. Single-crystal X-ray diffraction establishes the structures of both the interlocked precursor and the reconstructed product, while solution-state NMR spectroscopy and control experiments reveal a rapid and highly selective reconstruction process. Density functional theory calculations propose key intermediates and elucidate the dual mechanistic role of methanol during the reconstruction. Methanol promotes displacement of weakly coordinated triflate ligands and perturbs the local coordination environment, thereby initiating coordination-bond reorganization. Subsequent methanol coordination further recognizes the coordination framework and facilitates alkyne-sulfide addition that stabilizes the emerging octahedral architecture. The reconstruction therefore proceeds through coupled coordination-bond dynamics and covalent-bond formation rather than simple cage dissociation and reassembly. These findings provide a molecular-level mechanistic framework for understanding how solvent molecules can actively direct supramolecular reconstruction through the interplay of coordination chemistry and chemical reactivity.