Terphenyl derivatives as “turn on” fluorescent sensors for mercury

Abstract

New terphenyl-based reversible receptors 1−4 with pyrene and quinoline as the fluorophores have been designed, synthesized, and examined for their cation recognition abilities toward various cations (Sm³⁺, Nd³⁺, Pb²⁺, Hg²⁺, Ba²⁺, Cd²⁺, Ag⁺, Zn²⁺, Cu²⁺, Ni²⁺, Co²⁺, Fe²⁺, Fe³⁺, K⁺, Mg²⁺, Na⁺, and Li⁺) by UV−vis, fluorescence, and NMR spectroscopy. The prepared receptors showed the highly selective and sensitive “Off−On” fluorescence signaling behavior for Hg²⁺ ions in THF and mixed aqueous media (THF:H2O, 9.5:0.5).