176. Zwitterionic [4]Helicene: a Water-Soluble and Reversible pH Triggered ECD/CPL Chiroptical Switch in the UV and Red Spectral Regions
     Simon Pascal, Céline Besnard, Francesco Zinna, Lorenzo Di Bari, Boris Le Guennic, Denis Jacquemin, Jérôme Lacour
     Org. Biomol. Chem. 2016, 14, 4590-4594

The chiroptical switching properties of a readily accessible and water-soluble diaza [4]helicene are disclosed. This zwitterionic dye displays pH-dependent absorption and emission properties and this enables a reversible turn on/off of electronic circular dichroism at 300 nm and of circularly polarized luminescence in the red region upon protonation/deprotonation.

DOI: 10.1039/C6OB00752J 

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