Open-cage Fullerenes as Ligands

Abstract

Fullerene chemistry can be divided into “outer”, “inner” and “skeletal” chemistry. “Outer chemistry” is the chemical modifications of fullerenes, and “Inner chemistry” is the chemistry of endohedral metallofullerenes. “Skeletal Chemistry” is represented by the synthesis of a heterofullerene in which the carbon atom of fullerenes is replaced with a heteroatom such as a nitrogen atom, and the synthesis of an open-cage fullerene having an opening site inserted into a skeleton of fullerenes. The open-cage fullerene having a hetero atom in the opening site are expected to be used as ligands having a widely distorted π-conjugated system. In this mini-review, open-cage fullerenes inserted into metal complexes as ligands are introduced from recent studies.