The decarbonylation of a cage-opened C 60 derivative was examined by employing single-electron reductants. During the reaction, an H 2 O molecule was spontaneously encapsulated inside the cage (up to 78%) through the thus-formed 14membered-ring orifice even though the H 2 O encapsulation had long been considered to require an orifice consisting of at least 16 atoms. The crystallographic analysis revealed an orifice shape closer to a circle which significantly contributes to the decreased activation barrier for the H 2 O encapsulation.Letter pubs.acs.org/OrgLett

The amino-functionalized cage-opened [60]fullerene derivatives were synthesized by reactions with phenylenediamine. In this reaction, the diamine undergoes direct addition to the α,β-unsaturated carbonyl moiety. Further C−C bond scission is promoted by the intramolecular S N 2 reaction. These amino-functionalized derivatives possess high-lying highest occupied molecular orbital levels as suggested by electrochemical analyses. These compounds showed intense near-infrared absorption bands that tail to 900 nm, reflecting the optical transition with π−π* and charge transfer character.

The optical resolution of open-[60]­fullerenes has been limited to only one example since 1998, while the recent advances revealed the excellence of fullerenes as revisited chiral functional materials. Different from conventional chiral induction on [60]­fullerene by a multiple-functionalization, a random disruption of the spherical π-conjugation is avoidable for open-[60]­fullerenes. Moreover, the macrocyclic orifices enable a metal coordination which endows modulated electronic structures on chiral chromophores. Herein, we showcase Li+-coordination behavior and optical resolution of three chiral open-[60]­fullerene ligands, showing a giant dissymmetry factor up to 0.20 owing to a congenital topology of the spherical π-conjugation.