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

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 (similar to 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 x 10(-9) M in aqueous medium.