Columnar liquid-crystalline metallomacrocycles.

We report synthesis of novel macrocyclic molecules and their metal complexes as well as their thermotropic columnar liquid-crystalline behavior. The macrocyclic ligands were prepared size-selectively based on dynamic covalent chemistry. X-ray study of a model macrocycle with short alkyl chains revealed that they were discrete and highly symmetric, with an inner vacant cavity of 9 Å diameter enclosed by a 56π planar ring composed of four bis(salicylidene)-o-phenylenediamine (salphen) moieties alternating with four carbazoles.