Environmentally Benign Synthesis, Characterization, and Computational Studies of a Bidentate, Potentially Nonlinearly Optical Schiff Base and Its Transition Metal Complexes

Schiff bases are a significant group of synthetic molecules with widespread applications because they can form stable metal complexes, with conjugated Schiff bases possessing tuneable opto‐electronic properties. Conventional Schiff base syntheses often utilize harsh chemicals and conditions; therefore, an environmentally benign synthesis using natural acid catalysts from fruit juice extract has been reported and compared to a conventional synthesis. The Schiff base ligand (SBL) obtained from p ‐vanillin and 4‐nitro‐ o ‐phenylene diamine was further complexed with transition metals to verify the ligand's metal complexing ability. The resultant metal complexes were stable. The structures of the Schiff base and its metal complexes were deduced based on FTIR, 1 H NMR, electronic absorption spectra, thermogravimetric analysis, and density functional theory (DFT) studies. The reactivity and nonlinear optical (NLO) properties of SBL were studied using computational methods. The results indicate that SBL is a potential NLO material for upcoming opto‐electronic devices.