title: Insertion-coupling-cycloisomerization domino synthesis and cation-induced halochromic fluorescence of 2,4-diarylpyrano[2,3-b]indoles.
abstract: 2,4-Diarylpyrano[2,3-b]indoles are formed via a Pd-Cu-catalyzed insertion-coupling-cycloisomerization domino reaction in moderate yields. Although the tricyclic systems are nonfluorescent in solution, protonation, quaternation, or complexation with metal ions induces intense green luminescence. Most strikingly, selective halochromic fluorescence of zinc and magnesium over calcium ions classify the title compounds as metal-selective luminescence sensors.
authors.affiliation: Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, D-40225 Düsseldorf, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Schönhaber
authors.forename: Walter
authors.initials: W
authors.lastname: Frank
authors.forename: Thomas J J
authors.initials: TJ
authors.lastname: Müller
mesh_terms: D002412:Cations / Q000737:chemistry; D018360:Crystallography, X-Ray; D003500:Cyclization; D005456:Fluorescent Dyes / Q000138:chemical synthesis*; D007211:Indoles / Q000737:chemistry*; D007536:Isomerism; D008745:Methylation; D008958:Models, Molecular; D015394:Molecular Structure
chemical_list: D002412:Cations; D005456:Fluorescent Dyes; D007211:Indoles