title: Zwitterionic [4]helicene: a water-soluble and reversible pH-triggered ECD/CPL chiroptical switch in the UV and red spectral regions.
abstract: 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.
authors.affiliation: University of Geneva, Department of Organic Chemistry, quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland. Jerome.lacour@unige.ch.
authors.forename: Simon
authors.initials: S
authors.lastname: Pascal
authors.affiliation: Laboratory of Crystallography, University of Geneva, quai Ernest Ansermet 24, CH-1211 Geneva 4, Switzerland.
authors.forename: Céline
authors.initials: C
authors.lastname: Besnard
authors.affiliation: Università di Pisa, Dipartimento di Chimica e Chimica Industriale, Via G. Moruzzi 13, 56124 Pisa, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Zinna
authors.affiliation: Università di Pisa, Dipartimento di Chimica e Chimica Industriale, Via G. Moruzzi 13, 56124 Pisa, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Di Bari
authors.affiliation: Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes 1, 263 avenue du Général Leclerc, 35042 Rennes Cedex, France.
authors.forename: Boris
authors.initials: B
authors.lastname: Le Guennic
authors.affiliation: Laboratoire CEISAM, UMR 6230 CNRS, Université de Nantes, 2 rue de la Houssinière, BP 92208, 44322 Nantes Cedex 3, France and Institut Universitaire de France, 1, rue Descartes, F-75005 Paris Cedex 05, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Jacquemin
authors.affiliation: University of Geneva, Department of Organic Chemistry, quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland. Jerome.lacour@unige.ch.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Lacour