Efficient Self‐Sorting Behaviours of Metallacages with Subtle Structural Differences

Abstract Investigating the self‐sorting behaviour of assemblies with subtle structural differences is a captivating yet challenging endeavour. Herein, we elucidate the unusual self‐sorting behaviour of metallacages with subtle structural differences in batch reactors and microdroplets. Narcissistic self‐sorting of metallacages has been observed for two ligands with identical sizes, shapes, and symmetries, with only minor differences in the substituted groups. In particular, the self‐sorting process in microdroplets occurs within 1 min at room temperature, in stark contrast to batch reactors, which require equilibration for 30 min. To reveal the mechanism of self‐sorting and the role of microdroplets, we conducted a series of experiments and theoretical calculations, including competitive self‐assembly, cage‐to‐cage transformation, control experiments involving model metallacages with larger cavities, noncovalent interaction analysis, and root mean square deviation (RMSD) analysis. This research demonstrates an unusual case of self‐sorting of very similar assemblies and provides a new strategy for facilitating the self‐sorting efficiency of supramolecular systems.