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Merging polyacenes and cationic helicenes: from weak to intense chiroptical properties in the far red region† † Electronic supplementary information (ESI) available: Experimental conditions, full characterizations, 1H NMR and 13C NMR spectra of all new compounds (PDF); CSP-HPLC traces; UV-vis, ECD, fluorescence and CPL spectra; computational details. In addition, the dataset for this article can be found at the following DOI: 10.26037/yareta:zsmeadwn3vbgpag2jqno3lj554. It will be preserved for 10 years. CCDC 1960498–1960500. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c9sc05407c

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. Helical polyaza acenes, made from cationic [4] and [6]helicenes, display bright fluorescence. Only [6]helicene-derived tetracenes show enhanced ECD and CPL responses in the visible range as rationalized from first principles.

SUBMITTER: Duwald R

PROVIDER: S-EPMC8145434 | biostudies-literature |

REPOSITORIES: biostudies-literature

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