A phenanthroline–terpyridine hybrid as a chameleon-type ligand in a reversible metallosupramolecular rearrangement

Abstract

Phenanthroline–terpyridine hybrid 1 was designed as a chameleon-type ligand to satisfy both HETPHEN and HETTAP coordination modes. In the presence of Cu⁺, 1 exclusively self-assembled to triangle T1, whereas Zn²⁺ addition produced a 2 : 1 mixture of triangle T2 and square S2. Interconversion between T1 and (T2 + S2) states was triggered by the addition of Zn²⁺ and reversed by selectively removing Zn²⁺ with ligand 7.