A Highly Sensitive and Selective Fluorescence Chemosensor for Cu2+ and Zn2+ Based on Solvent Effect

A novel fluorescence chemosensor 1 based on (R)-binaphthyl-salen can exhibit highly sensitive and selective recognition responses toward Cu2+ by turn-off fluorescence quench type in THF/H2O, and Zn2+ by turn-on fluorescence enhancement type in CHCl3/CH3CN, respectively, suggesting that solvents can dramatically affect the responsive properties of salen-based chemosensor. In addition, Cu2+ can lead to the most pronounced changes of CD spectra without the influence of solvents, which indicates this kind chemosensor can also be used as a sole Cu2+ probe based on CD spectra.