Dual channel receptor based on diketopyrrolopyrrole alkyne conjugate for detection of Hg2+/Cu2+ by “naked eye” and fluorescence

A fluorescent probe 4 based on a diketopyrrolopyrrole alkyne conjugate structure was designed and synthesized, and its selective signaling behaviors toward Hg2+ and Cu2+ were investigated. Selective recognition of Hg2+ ion in aqueous solution was mediated through a reaction-based (Kucherov reaction) approach. Compound 4 selectively recognized Hg2+ as indicated by a color change from pink to blue and Cu2+ by a remarkable ratiometric absorption change accompanied by a color change from pink to colorless by utilizing the two reaction sites in compound 4.