Liquid-crystalline Metallomacrocycles Composed of Bis(hydroxypyridono)toluene Ligand and Cu Ions.

A series of π-extended chelating scaffolds incorporating two hydroxypyridone moieties were synthesized. X-ray crystallographic analysis revealed that a bis(hydroxypyridono)toluene ligand possessed a unique π-extended structure and exhibited efficient phase segregation from the aliphatic chains attached at the heterocyclic nitrogen. The bis-bidentate ligand formed a metal-coordination-induced macrocycle with Cu ions.