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Synthesis of a peripherally conjugated 5-6-7 nanographene.

ABSTRACT: A heteroaromatic nanographene containing a unique assembly of five-, six- and seven-membered rings is synthesized using oxidative coupling of an indole-containing precursor. Near-infrared absorption and emission properties of the nanographene core are enhanced by peripheral expansion and ring fusion at all oxidation levels. The dicationic state shows distinct aromaticity originating from a peripheral ?-conjugated circuit. A partially coupled intermediate, trapped in the synthesis of the 5-6-7 nanographene, is explored as a reference system, showing an unexpected reduction of the optical band gap due to intramolecular charge transfer.

SUBMITTER: Zyla M

PROVIDER: S-EPMC5952525 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Synthesis of a peripherally conjugated 5-6-7 nanographene.

Żyła Marika M Gońka Elżbieta E Chmielewski Piotr J PJ Cybińska Joanna J Stępień Marcin M

Chemical science 20150929 1

A heteroaromatic nanographene containing a unique assembly of five-, six- and seven-membered rings is synthesized using oxidative coupling of an indole-containing precursor. Near-infrared absorption and emission properties of the nanographene core are enhanced by peripheral expansion and ring fusion at all oxidation levels. The dicationic state shows distinct aromaticity originating from a peripheral π-conjugated circuit. A partially coupled intermediate, trapped in the synthesis of the 5-6-7 na ...[more]

PMID: 29861982

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