Highly Anisotropic PdL L and PdL L Type Cages by Heteromeric Completive Self-Sorting.

Pd(II)-based low-symmetry coordination cages possessing anisotropic cavities are of great interest. The common strategies employed to achieve such cages utilize either more than one type of symmetrical ligands (e.g., L, L etc.) or only one type of unsymmetrical ligand (e.g., L). To significantly enhance the anisotropy, we have designed two unsymmetrical bidentate ligands i.e., L and L, aiming at a low-symmetry PdL L -type cage. It was accomplished by high-fidelity integrative self-sorting of two different low-symmetry cages having PdL and PdL -type architectures (homoleptic complexes of the designed ligands). Structural constraints and geometry complementarity in the ligand design drive the non-statistical exclusive self-assembly of the PdL L -type cage. By taking advantage of the complemental geometries between ligands, a low-symmetry PdL L -type cage was also obtained. Heteromeric completive self-sorting of three homoleptic assemblies (PdL , PdL and PdL -type cages) into an exclusive mixture of PdL L and PdL L -type mixed ligated assemblies was demonstrated through cage-to-cage transformations.