A new coumarin-carbonothioate-based turn-on fluorescent chemodosimeter for selective detection of Hg2+

A new fluorescent chemodosimeter 1 comprising coumarin as a fluorophore and a carbonothioate group as recognition unit was designed and synthesized. Its structure was confirmed by single crystal X-ray crystallography. The compound 1 shows almost no fluorescence in HEPES buffer (10 mM, pH 7.0), while displays obvious fluorescence enhancement after addition of Hg2+ over other metal ions. The recognition mechanism is attributed to the Hg2+-promoted hydrolysis reaction. In addition, 1 could be successfully applied to detect the concentrations of Hg2+ in real water samples by fluorescence turn-on response.