A novel 2-(2′-aminophenyl)benzothiazole derivative displays ESIPT and permits selective detection of Zn2+ ions: experimental and theoretical studies

Abstract

Synthesis of a novel 2-(2′-aminophenyl)benzothiazole based probe (1) and demonstration of excited state intramolecular proton transfer (ESIPT) with a large Stokes shift (∼246 nm) are presented. Selective interactions of probe 1 with DMSO and Zn²⁺ result in the inhibition of ESIPT operating in 1. Inhibition of ESIPT by only Zn²⁺ and not by other common metal ions permits the selective detection of Zn²⁺ at concentrations as low as 4.5 × 10⁻⁹ M in aqueous medium.