Solvent-Dependent Self-Assembly and Crystal Structures of a Salen-Based Macrocycle

A salen-based macrocycle possessing adamantane units was constructed from two ethylenediamine and two disubstituted adamantane-bearing salicylaldehyde components. The addition of methanol to a tetrahydrofuran solution of the macrocycle afforded the crystals via hollow spherical and fused aggregates, and X-ray crystallographic analysis showed that the macrocycle had a rhomboidal structure. The use of chloroform instead of methanol gave the crystals of a square-shaped macrocycle without the formation of self-assembled materials.