A Coumarin-Derived Fluorescence Chemosensors Selective for Copper(II)

Abstract

Abstract Two different coumarin derivatives have been connected via animine linkage to obtain a new fluorescence signaling system. The coumarin derivative (L) containing a C-N group was designed as an example for illustration. The free ligand L is almost nonfluorescent due to the isomerization of C-N double bond in the excited state. However, in the presence of a Cu(II) ion, this isomerization is stopped because of bonding to the metal ion, resulting in a high-intensity (400-fold) emission. In this way, we designed a new compound for copper-selective and ratiometric chemosensors.