Selective Synthesis of Discrete Mono‐, Interlocked‐, and Borromean Ring Ensembles Based on a π‐Electron‐Deficient Ligand

Herein, we present a new synthetic approach to achieve selective supramolecular transformations and construct different interlocked metallacycles featuring a π‐electron‐deficient thiazolo5,4‐d]thiazole‐derived ligand. We demonstrate that the formation of mono‐rings, interlocked rings (2]catenanes) and Borromean rings can be controlled by adjusting the length of the binuclear half‐sandwich Rh^III and Ir^III building blocks. Furthermore, a concentration effect or D‐A stacking interaction between the pyrene guest and the thiazolo5,4‐d]thiazole‐based ligand promotes a unique and reversible conversion between catenane structures and metalla‐rectangles. The synthetic results are supported by single‐crystal X‐ray diffraction analysis.