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A [2]Rotaxane-Based Circularly Polarized Luminescence Switch.

ABSTRACT: A rotaxane-based molecular shuttle has been synthesized in which the switching of the position of a fluorescent macrocycle on the thread turns "on" or "off" the circularly polarized luminescence (CPL) of the system while maintaining similar fluorescence profiles and quantum yields in both states. The chiroptical activity relies on the chiral information transfer from an ammonium salt incorporating d- or l-phenylalanine residues as chiral stereogenic covalent units to an otherwise achiral crown ether macrocycle bearing a luminescent 2,2'-bipyrene unit when they interact through hydrogen bonding. Each enantiomeric thread induces CPL responses of opposite signs on the macrocycle. Upon addition of base, the switching of the position of the macrocycle to a triazolium group disables the chiral information transfer to the macrocycle, switching "off" the CPL response. The in situ switching upon several acid/base cycles is also demonstrated.

SUBMITTER: David AHG

PROVIDER: S-EPMC6975276 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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A [2]Rotaxane-Based Circularly Polarized Luminescence Switch.

David Arthur H G AHG Casares Raquel R Cuerva Juan M JM Campaña Araceli G AG Blanco Victor V

Journal of the American Chemical Society 20191101 45

A rotaxane-based molecular shuttle has been synthesized in which the switching of the position of a fluorescent macrocycle on the thread turns "on" or "off" the circularly polarized luminescence (CPL) of the system while maintaining similar fluorescence profiles and quantum yields in both states. The chiroptical activity relies on the chiral information transfer from an ammonium salt incorporating d- or l-phenylalanine residues as chiral stereogenic covalent units to an otherwise achiral crown e ...[more]

PMID: 31638802

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