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Functionalized cationic [4]helicenes with unique tuning of absorption, fluorescence and chiroptical properties up to the far-red range.

ABSTRACT: Unprecedented regioselective post-functionalization of racemic and enantiopure cationic diaza [4]helicenes is afforded. The peripheral auxochrome substituents allow a general tuning of the electrochemical, photophysical and chiroptical properties of the helical dyes (26 examples). For instance, electronic absorption and circular dichroism are modulated from the orange to near-infrared spectral range (575-750 nm), fluorescence quantum efficiency is enhanced up to 0.55 (631 nm) and circularly polarized luminescence is recorded in the red (|g_lum| ∼ 10^-3).

SUBMITTER: Delgado IH

PROVIDER: S-EPMC5772034 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Functionalized cationic [4]helicenes with unique tuning of absorption, fluorescence and chiroptical properties up to the far-red range.

Delgado I Hernández IH Pascal S S Wallabregue A A Duwald R R Besnard C C Guénée L L Nançoz C C Vauthey E E Tovar R C RC Lunkley J L JL Muller G G Lacour J J

Chemical science 20160408 7

Unprecedented regioselective post-functionalization of racemic and enantiopure cationic diaza [4]helicenes is afforded. The peripheral auxochrome substituents allow a general tuning of the electrochemical, photophysical and chiroptical properties of the helical dyes (26 examples). For instance, electronic absorption and circular dichroism are modulated from the orange to near-infrared spectral range (575-750 nm), fluorescence quantum efficiency is enhanced up to 0.55 (631 nm) and circularly pola ...[more]

PMID: 29348909

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