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Cata-Annulated Azaacene Bisimides.

ABSTRACT: Ultra-electron-deficient azaacenes were synthesized via Buchwald-Hartwig coupling of ortho-diaminoarenes with chlorinated mellophanic diimide followed by oxidation of the intermediate N,N'-dihydro compounds with MnO₂ or PbO₂ . The resulting cata-annulated bisimide azaacenes have ultrahigh electron affinities with first reduction potentials as low as -0.35 V recorded for a tetraazapentacene. Attempts to prepare a tetrakis(dicarboximide)tetraazaheptacene resulted in the formation of a symmetric butterfly dimer.

SUBMITTER: Elter M

PROVIDER: S-EPMC8457205 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Cata-Annulated Azaacene Bisimides.

Elter Maximilian M Ahrens Lukas L Luo Stella M SM Rominger Frank F Freudenberg Jan J Cao Dennis D DD Bunz Uwe H F UHF

Chemistry (Weinheim an der Bergstrasse, Germany) 20210729 48

Ultra-electron-deficient azaacenes were synthesized via Buchwald-Hartwig coupling of ortho-diaminoarenes with chlorinated mellophanic diimide followed by oxidation of the intermediate N,N'-dihydro compounds with MnO<sub>2</sub> or PbO<sub>2</sub> . The resulting cata-annulated bisimide azaacenes have ultrahigh electron affinities with first reduction potentials as low as -0.35 V recorded for a tetraazapentacene. Attempts to prepare a tetrakis(dicarboximide)tetraazaheptacene resulted in the forma ...[more]

PMID: 34196059

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