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Merging polyacenes and cationic helicenes: from weak to intense chiroptical properties in the far red region.

ABSTRACT: A series of helical tetracenes and pentacenes was synthesized from cationic [6] and [4]helicene precursors. These colorful acenes fluoresce in the far red region. While [4]helicene-based pentacenes exhibit chiroptical properties mainly in the UV region, [6]helicene-derived tetracenes show enhanced ECD in the visible range, in addition to clear CPL responses. This difference is rationalized using first principles.

SUBMITTER: Duwald R

PROVIDER: S-EPMC8145434 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Merging polyacenes and cationic helicenes: from weak to intense chiroptical properties in the far red region.

Duwald Romain R Bosson Johann J Pascal Simon S Grass Stéphane S Zinna Francesco F Besnard Céline C Di Bari Lorenzo L Jacquemin Denis D Lacour Jérôme J

Chemical science 20191205 4

A series of helical tetracenes and pentacenes was synthesized from cationic [6] and [4]helicene precursors. These colorful acenes fluoresce in the far red region. While [4]helicene-based pentacenes exhibit chiroptical properties mainly in the UV region, [6]helicene-derived tetracenes show enhanced ECD in the visible range, in addition to clear CPL responses. This difference is rationalized using first principles. ...[more]

PMID: 34084373

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