Metallo-Supramolecular Self-Assembly of a Multicomponent Ditrigon Based on Complementary Terpyridine Ligand Pairing

Predesigned complementary complexation
of two 2,2′:6′,2″-terpyridine-based
ligands was established by installing 2,6-dimethoxyphenyl substituents
at the terpyridyl 6,6″-positions, which provided ancillary
ion–dipole interactions in the coordination process and extra
π-stacking stabilization in the resultant heteroleptic complex.
The high-fidelity self-recognition ligation afforded facile access
to the quantitative self-assembly of multicomponent triangle [Cd6L33L43] and ditrigon [Cd15L36L53] (that is, a hexagon with six
120° angles and two alternating edge lengths). It was found that
the linear 6,6″-substituted ditopic motif (L3) would be directed by the ligand geometry of L5 to selectively incorporate into
the parallel homoleptic connections in the bilayered framework.