Synthesis, characterization, antioxidant activities and DFT calculations of 2,4-bis (2-hydroxy-3-methoxy benzaldehyde) diiminotoluene Schiff base

2,4-Bis (2-hydroxy-3-methoxybenzaldehyde) diiminotoluene Schiff base (SB) derived from 2,4-diaminotoluene and 2-hydroxy-3-methoxybenzaldehyde was synthesized and characterized using spectroscopic analysis: the Nuclear Magnetic Resonance (1H, 13C NMR), the Fourier Transform Infrared and the ultraviolet–visible. This synthesized compound was evaluated using the spectrophotometric chemical tests including the β-carotene bleaching test, hydroxyl radical scavenging, reducing power test, DPPH test, ABTS test and the electrochemical test (superoxide radical scavenging test). These tests were used to specify the ability of the ligand SB to scavenge the free radicals. The results illustrate that SB is useful as an antioxidant. Moreover, the structure–activity was explained utilizing the Density Functional Theory to determine the Frontier Molecular Orbital, Mulliken, Natural Bond Orbital atomic charges and Molecular Electrostatic Potential. The cyclic voltammetry was used to set the electrochemical properties of the Schiff base.