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Reversible reduction drives anion ejection and C60 binding within an FeII4L6 cage† † Electronic supplementary information (ESI) available. CCDC 1935513. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c9sc05728e

ABSTRACT: FeII4L6 tetrahedral cage 1 was prepared from a redox-active dicationic naphthalenediimide (NDI) ligand. The +20 charge of the cage makes it a good host for anionic guests, with no binding observed for neutral aromatic molecules. Following reduction by Cp2Co, the cage released anionic guests; subsequent oxidation by AgNTf2 led to re-uptake of anions. In its reduced form, however, 1 was observed to bind neutral C60. The fullerene guest was subsequently ejected following cage re-oxidation. The guest release process was found to be facilitated by anion-mediated transport from organic to aqueous solution. Cage 1 thus employs electron transfer as a stimulus to control the uptake and release of both neutral and charged guests, through distinct pathways. FeII4L6 cage 1 binds anionic guests but not neutral guests. In its reduced form, the cage can bind neutral C60. Reduction and oxidation of the cage could thus be used as a stimulus to control the uptake and release of both neutral and charged guests.

SUBMITTER: Lu Z

PROVIDER: S-EPMC8146419 | biostudies-literature |

REPOSITORIES: biostudies-literature

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