Azine Based Oligoesteric Chemosensors for Cu2+ Ion Detection: Synthesis, Structural Characterization, and Theoretical Investigations

Synthesized monomer and its three oligoester were characterized by technique such as ¹ H, ¹³ C, IR,UV, GPC and applied to chemosensor applications. A series of metal ion was studied with fluorophores to evaluate the sensitivity towards Cu ²⁺ ion. The fluorophores results exhibit the selective and sensitive “turn off” fluorescence response with Cu ²⁺ ion in DMF/H ₂ O (1:1, pH: 7.4, fluorophore: 5µM) solution. Binding stoichiometry and binding constant of fluorophores were calculated using Stern-Volmer equation and Benesi–Hildebrand plots respectively. Structure of fluorophores were studied using DFT, B3LYP/6–311 + + G(d,p) level basis set. Quenching mechanism and electrical properties of fluorophores were explained with theoretical outcomes. Iodine doped and undoped oligoesters electrical conductivity were studied in solid-state and the conductivity was gradually increase with increase the contact time of iodin with oligoesters. At different frequencies and temperatures, the dielectric measurement was calculated using the two-probe method. Among all oligoesters, DMDAP exhibited high electrical conductivity and DMDMP has high dielectric constant value than other oligoesters.