A Simple Fluorescent Chemosensor for Mg2+Based on C=N Isomerization with Highly Selectivity and Sensitivity

A simple fluorescent chemosensor based on naphthalene has been prepared. It was shown to be selective for Mg2+ in acetonitrile based on C=N isomerization. The free ligand showed quite weak fluorescence emission due to the isomerization of C=N double bond in the excited state, however, after addition of Mg2+, fluorescence emission results in a prominent fluorescence enhancement.