2 H -Pyran-2-one-Functionalized Diketopyrrolopyrrole Dye: Design, Synthesis, and Explosives Sensor.

In this work, a 2 H -pyran-2-one-functionalized diketopyrrolopyrrole (DPP) (coded as receptor 1 ) was designed, synthesized, and fully characterized by various spectroscopic methods. The physical properties of molecular architecture 1 were studied employing theoretical calculations. Receptor 1 was elegantly scrutinized for the sensing of explosive nitroaromatic compounds (NACs). Receptor 1 exhibited detection of nitro explosives, i.e., picric acid (PA), 2,4-dinitrophenol (DNP), and nitrophenol (NP), via the fluorescence quenching mechanism. The Stern-Volmer equation was employed to evaluate the effectiveness of the quenching process. It was found that 1 exhibited a detection limit of about 7.58 × 10 -5 , 8.35 × 10 -5 , and 9.05 × 10 -5 M toward PA, DNP, and NP, respectively. The influence of interfering metal ions and anions on PA detection was investigated thoroughly. Furthermore, receptor 1- based low-cost fluorescent thin-layer chromatography (TLC) plates were developed for the recognition of PA.