ChemInform Abstract: Insertion-Coupling-Cycloisomerization Domino Synthesis and Cation-Induced Halochromic Fluorescence of 2,4-Diarylpyrano[2,3-b]indoles.

Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, D-40225 Düsseldorf, Germany.
Organic Letters (Impact Factor: 6.36). 09/2010; 12(18):4122-5. DOI: 10.1021/ol101709p
Source: PubMed

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.

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