Temperature-, Concentration-, and Solvent-Dependent <i>M</i> / <i>P</i> Helicity Switching of Double-Helical Monometallofoldamers with Inversion of Circularly Polarized Luminescence
Fluorescent double-helical monometallofoldamers [Ag-(<b>1</b>)<sub>2</sub>]-[PF<sub>6</sub>] were constructed by the mononuclear complexation of two bipyridine strands <b>1</b> featuring two L-shaped dibenzopyrrolo-[1,2-<i>a</i>]-[1,8]-naphthyridine units at both ends with a Ag-(I) cation. These monometallofoldamers exhibited double-helical/open conformational switching. [(<i>R</i>)-Ag-(<b>1c</b>)<sub>2</sub>]-[PF<sub>6</sub>] with chiral side chains induced a single-handed helix sense and enabled precise control of <i>M</i>/<i>P</i> helicity switching in response to a solvent. This complex also exhibited strong fluorescence and circularly polarized luminescence (CPL) inversion switching upon <i>M</i>/<i>P</i> helicity inversion. For instance, [(<i>R</i>)-Ag-(<b>1c</b>)<sub>2</sub>]-[PF<sub>6</sub>] exhibited positive CPL in CH<sub>2</sub>Cl<sub>2</sub> (φ<sub>F</sub> = 0.69, <i>g</i> <sub>lum</sub> = 1.9 × 10<sup>-3</sup>) and negative CPL in toluene (φ<sub>F</sub> = 0.79, <i>g</i> <sub>lum</sub> = -2.0 × 10<sup>-3</sup>). This double helix also aggregated in polar solvents, which led to CPL inversion switching induced by temperature- and concentration-dependent aggregation.
Authors
- Hidetoshi Kawai (ORCID: https://orcid.org/0000-0002-3367-0153)
- Yoshitaka Tsuchido (ORCID: https://orcid.org/0000-0001-8860-0745)
- Kotaro Matsumura
- Daiki Tauchi
- Masashi Hasegawa
Institutions
- Tokyo University of Science (JP)
- Kitasato University (JP)
Publication Details
- Journal
- JACS Au
- Published
- 2026-01-30
- DOI
- https://doi.org/10.1021/jacsau.5c01659
- Primary Topic
- Synthesis and Properties of Aromatic Compounds
- Type
- article
- Field-Weighted Citation Impact
- 0.00