title: A Ratiometric Luminescent Switch Based on Platinum Complexes Tethered to a Crown-Ether Scaffold.
abstract: A ratiometric chemosensor for potassium is reported, based on phosphorescent dinuclear cyclometalated Pt(II) complexes featuring a cis-crown ether as the cation-recognition unit. The metal complexes are blue luminescent in a non-aggregated state but become strongly orange emissive when in a close physical proximity, as is the case when the macrocycle is in the folded state. Upon binding of the cation, unfolding occurs, resulting in a pronounced change in the emission properties (e.g. emission wavelength), which can be used for ratiometric sensing applications. The reversibility of the binding was confirmed by competitive titration experiments with unsubstituted 18-crown-6; the system shows supramolecular switching behavior.
authors.affiliation: Institut de Science et d'Ingénierie Supramoléculaires (ISIS), Université de Strasbourg & CNRS, 8 Rue Gaspard Monge, 67083, Strasbourg, France.
authors.forename: Stephan
authors.initials: S
authors.lastname: Sinn
authors.affiliation: Institute for Nanotechnology (INT), Karlsruhe Institut für Technologie, Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Biedermann
authors.affiliation: Organic Chemistry Department, University of Geneva, Quai Ernest Ansermet 30, 1211, Geneva 4, Switzerland.
authors.forename: Mahesh
authors.initials: M
authors.lastname: Vishe
authors.affiliation: Institut de Science et d'Ingénierie Supramoléculaires (ISIS), Université de Strasbourg & CNRS, 8 Rue Gaspard Monge, 67083, Strasbourg, France.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Aliprandi
authors.affiliation: Laboratory of Crystallography, University of Geneva, Quai Ernest Ansermet 24, 1211, Geneva 4, Switzerland.
authors.forename: Céline
authors.initials: C
authors.lastname: Besnard
authors.affiliation: Organic Chemistry Department, University of Geneva, Quai Ernest Ansermet 30, 1211, Geneva 4, Switzerland. jerome.lacour@unige.ch.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Lacour
authors.affiliation: Institut de Science et d'Ingénierie Supramoléculaires (ISIS), Université de Strasbourg & CNRS, 8 Rue Gaspard Monge, 67083, Strasbourg, France. decola@unistra.fr.|Institute for Nanotechnology (INT), Karlsruhe Institut für Technologie, Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany. decola@unistra.fr.
authors.forename: Luisa
authors.initials: L
authors.lastname: De Cola
keywords: emission-based sensing; host-guest systems; luminescent metal complexes; molecular switches; supramolecular chemistry