Spectroscopic and Theoretical Studies and Intramolecular Proton Transfer in (Z)-2-Hydroxy-6-(((2-methoxy-5-(trifluoromethyl)phenyl)amino)methylene)cyclohexa-2,4-dien-1-one

In present work, a new Schiff base compound, (E)-3-(((2-methoxy-5-(trifluoromethyl)phenyl)imino)methyl)benzene-1,2-diol was synthesized and characterized by X-ray diffraction and spectroscopic methods (FT-IR, UV–Vis) and quantum mechanical calculation methods. The obtained structure is monoclinic, space group P 2 1 / c , with unit cell parameters a = 15.1881(10) Å, b = 14.5816(11) Å, c = 6.2023(5) Å, β = 98.008 (6)°, and Z = 4. Theoretical calculations were used to investigate the optimized molecular geometry of the title compound. The calculated and experimental results show the title compound tends to the keto-amine form. Besides, the frontier molecular orbital, non-linear optical properties and electronic structure parameters of the title compound were computed in the solvent media using the theoretical methods. The molecular electrostatic potential surface was obtained at the optimized geometry to predict reactive sites for nucleophilic and electrophilic attack for the studied molecule. Statistical thermodynamic functions for the title compound were calculated at 298.15 K temperature and 1 atm pressure by using the HF and DFT/B3LYP methods with the 6-311++G( d , p ) basis set.