Synthesis of Di(thiophen-2-yl) Substituted Pyrene-Pyridine Conjugated Scaffold and DFT Insights: A Selective and Sensitive Colorimetric, and Ratiometric Fluorescent Sensor for Fe(III) Ions.

In this context, we used the multicomponent Chichibabin pyridine synthesis reaction to synthesize a novel di(thiophen-2-yl) substituted and pyrene-pyridine fluorescent molecular hybrid. The computational (DFT and TD-DFT) and experimental investigations were performed to understand the photophysical properties of the synthesized new structural scaffold. The synthesized ligand displays highly selective fluorescent sensing properties towards Fe ions when compared to other competitive metal ions (Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, Na, Ni, Pb, Sr, Sn and Zn). The photophysical properties studies reveal that the synthesized hybrid molecule has a binding constant of 2.30 × 10 M with limit of detection (LOD) of 4.56 × 10 M (absorbance mode) and 5.84 × 10 M (emission mode) for Fe ions. We believe that the synthesized pyrene-conjugated hybrid ligand can serve as a potential fluorescent chemosensor for the selective and specific detection of Fe ions.