An anthracene-based fluorescent chemosensor for Zn2+

A new zinc ion sensor 1-(anthracen-9-yl)-N-(pyridin-2-ylmethyl)-N-(quinolin-2-ylmethyl)methanamine 1 was synthesized by incorporating a dipicolylamine derivative as a binding unit and an anthracene group as a fluorescence signaling unit. The anthracene-based receptor 1 was highly selective for Zn2+ with a fluorescence enhancement and a remarkable red shift in aqueous solution, whereas this chemosensor showed no response to other metals, especially Cd2+ ion. The composition of the complex 1-Zn2+ turned out 1:1, based on Job's plot, ESI-mass analysis, and 1H NMR titration.