Pyrene Substituted Phthalonitrile Derivative As a Fluorescent Sensor For Detection of Fe3+ Ions in Solutions

Abstract

In this current study, the novel bis[4,5-(pyrene-2-yl)-3,6-(hexyloxy)] phthalonitrile (SPN) fluorophore has been successfully synthesized. Structural characterization of this novel compound was performed by different spectroscopic methods such as FT-IR, MALDI-TOF, H-1-NMR, C-13-NMR and elemental analyses as well. In addition, the photophysical properties were determined using UV-vis absorption, steady-state fluorescence, time-resolved fluorescence spectroscopic methods and quantum chemical calculations. The metal sensing behavior of the SPN was determined in the presence of various metals (Li+, Na+, K+, Mg2+, Ca2+, Ba2+, Mn2+, Fe3+, Cr3+, Co2+, Ni2+, Ag+, Cd2+, Al3+, Hg+ and Zn2+) using fluorescence spectroscopy. The novel pyrene based phthalonitrile (SPN) showed high sensitivity and selectivity towards Fe3+ ion over other examined metal ions. In order to perform the determination of Fe3+ ion in environmental samples, experimental conditions such as selectivity, stability, precision, sensitivity, accuracy and recovery were optimized. Also, the complex stoichiometry of the novel pyrene based phthalonitrile (SPN) and Fe3+ ions was determined by a Job's plot. The compound was also studied via density functional theory calculations revealing the interaction mechanism of the molecule with Fe3+ ions.