Design and Synthesis of Novel Thiophene based Chelator Ligand for Enhanced Sensing of Fe2+ ions: An Experimental and Theoretical Insights

Abstract

In the present study, we have reported the synthesis of a novel thiophene - based dipodal chelator ligand MPT (N1, N3-bis(3-((E)-thiophen-2-yl)methylene)amino)propyl)malonamide). Further, the physio-chemical properties of as-synthesized ligand was analyzed employing state-of-the-art characterization tools such as 1H NMR, 13C NMR, and IR spectroscopy. In order to calculate the protonation constant for the ligand MPT and formation constants for the ligand MPT with Fe2+ metal ion potentiometric and spectrophotometric analysis were carried out. Further, to analyze the coordination behavior of the ligand MPT with Fe2+ metal ion at room temperature in a highly aqueous medium spectrophotometric analysis was carried out. On the other hand, the theoretical studies for the ligand MPT and its complex with Fe2+ ion were performed employing a semi-empirical method and density functional theory. Further, the structure optimization of the ligand MPT was obtained using the PM6 parameter and B3LYP/6-311(d,p) level for ligand and DGDZVP for metal complex calculations respectively.