Abstract: Schiff-base receptors have been of recent interest as colorimetric chemical sensors for detection of anions and cations due to their generally simple method of synthesis [1]. Herein, we report the condensation product of azo-coupled precursor (2-hydroxy-5-(naphthalen-1-yldiazenyl) benzaldehyde) and 4-Chloro-3(trifluoromethyl)benzylamine, 2-((E)-((4-chloro-3-(trifluoromethyl)phenyl)imino)methyl)-4-((E)-naphthalen-1-yldiazenyl)phenol (L) acts as a colorimetric chemical sensor. The structure of (L) (Fig 1) was studied with the help of UV–Vis, FT-IR and1H-NMR techniques [2]. The synthesized compound was introduced for the selective detection of anions in organic and semi-organic media. The interaction between the ionophores and anions was investigated by NMR and UV–Vis methods [3]. Fig 1.Structure of Schiff-base receptor