The Synthesis, Structure, and Supramolecular Chemistry of Anthracene Rings and Cages

Abstract

Macrocyclic rings and cages were constructed by assembling anthracene units to create novel aromatic compounds. Key building units, 2,7─ dibromoanthrcene derivatives, were prepared by classical methods or using an improved method via the Hartwig─ Miyaura borylation. Tripodal triptycene units required for the cage structures were prepared by regioselective bromination. Macrocyclization of the anthracene units by the Yamamoto coupling afforded cyclic hexamers having disk─ shaped nonplanar frameworks. A hexameric ring without inner substituents formed Saturn─ shaped supramolecular host─ guest complexes with fullerene guests C 60 and C 70 via multipoint C-H…π interactions. Cages prepared by coupling reactions also formed stable complexes with the fullerene guests. Some related studies of the anthracene─ based rings and cages are introduced. The signi cance of and perspectives for the chemistry of anthracene rings and cages are reviewed.