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Reversible reduction drives anion ejection and C₆₀ binding within an Fe^II ₄L₆ cage.

ABSTRACT: Fe^II ₄L₆ 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.

SUBMITTER: Lu Z

PROVIDER: S-EPMC8146419 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Reversible reduction drives anion ejection and C60 binding within an FeII 4L6 cage.

Lu Zhenpin Z Ronson Tanya K TK Nitschke Jonathan R JR

Chemical science 20191205 4

FeII 4L6 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. T ...[more]

PMID: 34084365

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