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Combined reversible switching of ECD and quenching of CPL with chiral fluorescent macrocycles.

ABSTRACT: Straightforward synthesis and resolution of a series of chiral fluorescent macrocycles are presented, together with their electronic circular dichroism (ECD), strong excimer fluorescence (EF, ? 300 to 650 nm) and allied highly circularly polarized luminescence (CPL, g _lum up to 1.7 × 10^-2). The ECD, EF and CPL responses are strongly affected by the presence of metal ions (Na⁺, Ba²⁺) thanks to deep conformational changes. While ECD signals can be almost completely reversibly inverted upon the complexation/decomplexation of metal ions in a typical binary response, CPL signals are reversibly quenched concomitantly. The designed macrocycles display thus a remarkable combination of both +/- ECD and on/off CPL reversible switching.

SUBMITTER: Homberg A

PROVIDER: S-EPMC6137439 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Combined reversible switching of ECD and quenching of CPL with chiral fluorescent macrocycles.

Homberg Alexandre A Brun Elodie E Zinna Francesco F Pascal Simon S Górecki Marcin M Monnier Luc L Besnard Céline C Pescitelli Gennaro G Di Bari Lorenzo L Lacour Jérôme J

Chemical science 20180801 35

Straightforward synthesis and resolution of a series of chiral fluorescent macrocycles are presented, together with their electronic circular dichroism (ECD), strong excimer fluorescence (EF, λ 300 to 650 nm) and allied highly circularly polarized luminescence (CPL, g lum up to 1.7 × 10-2). The ECD, EF and CPL responses are strongly affected by the presence of metal ions (Na+, Ba2+) thanks to deep conformational changes. While ECD signals ...[more]

PMID: 30310624

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