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Pyridinium-Functionalized Pyromellitic Diimides with Stabilized Radical Anion States.

ABSTRACT: In this work, we report the stabilization of the reduced states of pyromellitic diimide by charge-balancing the imide radical anions with cationic pyridinium groups attached to the aromatic core. This structural modification is confirmed by single-crystal X-ray diffraction analysis. Characterization by (spectro)electrochemical experiments and computations reveal that the addition of cationic groups to an already electron-deficient ring system results in up to +0.57 V shifts in reduction potentials, largely as a consequence of charge screening and lowest unoccupied molecular orbital-lowering effects. This formal charge-balancing approach to stabilizing the reduced states of electron-deficient pyromellitic diimides will facilitate their incorporation into spin-based optoelectronic materials and devices.

SUBMITTER: Greenlee AJ

PROVIDER: S-EPMC6045377 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Pyridinium-Functionalized Pyromellitic Diimides with Stabilized Radical Anion States.

Greenlee Andrew J AJ Ofosu Charles K CK Xiao Qifan Q Modan Mohammed M MM Janzen Daron E DE Cao Dennis D DD

ACS omega 20180109 1

In this work, we report the stabilization of the reduced states of pyromellitic diimide by charge-balancing the imide radical anions with cationic pyridinium groups attached to the aromatic core. This structural modification is confirmed by single-crystal X-ray diffraction analysis. Characterization by (spectro)electrochemical experiments and computations reveal that the addition of cationic groups to an already electron-deficient ring system results in up to +0.57 V shifts in reduction potentia ...[more]

PMID: 30023774

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