[60]Fullerene‐Based Macrocycle Ligands

Macrocycle ligands have three or more donor sites. Selective replacement of skeleton carbon atoms by heteroatoms and vacancies in C 60 could lead to various macrocycle ligands with a cage‐shaped backbone. Theoretical calculations indicate that such C 60 ‐based macrocycle ligands are as stable as C 60 thermodynamically according to their similar HOMO–LUMO gaps. The synthesis of these ligands is a challenging task. Nevertheless important progresses have been reported. This concept article focuses on the structures of possible C 60 ‐based macrocycle ligands and related synthetic results.