Designing Narcissistic Self-Sorting Terpyridine Moieties with High Coordination Selectivity for Complex Metallo-Supramolecules

Abstract

Coordination-driven self-assembly serves as a powerful approach for the construction of metallo-supramolecules, however, it still remains its infancy in design of coordination moieties with high selectivity and specificity. Herein, two unique ortho-modified terpyridine ligands (MA and MB) were designed and synthesized to form head-to-tail coordination complexes with Zn(II) respectively. Both of them showed excellent narcissistic self-sorting process due to the exquisite design. Further, two multitopic ligands (LA and LB) with narcissistic self-sorting moieties were obtained and used to construct more complex metallo-supramolecules hexagons. More interestingly, because of the non-coaxial structural restrictions in the rotation of terpyridine moieties, the obtained hexagonal macrocycles were able to hierarchically self-assemble into giant cyclic nanostructures via side-to-side stacking rather than face-to-face stacking. Our design of dissymmetrical coordination moieties could pave a new avenue for the development of congested coordination pairs with high selectivity and specificity.