Theoretical and experimental investigation of 4-[(2-hydroxy-3-methylbenzylidene)amino]benzenesulfonamide: Structural and spectroscopic properties, NBO, NLO and NPA analysis

Abstract

The sulfonamide compound, 4-[(2-hydroxy-3-methylbenzylidene)amino]benzenesulfonamide was synthesized and grown as a high quality single crystal by the slow evaporation solution growth technique. The structure of the compound was characterized by FT-IR, 1H and 13C NMR, UV–Vis and X-ray single crystal techniques. The compound crystallizes in the monoclinic space group Cc with a=4.9690 (4)Å, b=29.3068 (14)Å, c=9.4490 (8)Å, and β=97.174 (6)°, and Z=4 in the unit cell. Density functional theory (DFT) calculations were carried out for the title compound by utilizing DFT level of theory using B3LYP/6-311++G(d,p) as basis set. The theoretical vibrational frequencies, 1H and 13C NMR chemical shifts, absorption wavelengths and optimized geometric parameters such as bond lengths and bond angles were calculated by using quantum chemical methods. In addition, DFT calculations of the title compound, Molecular Electrostatic Potential (MEP), Natural Bond Orbital (NBO), Frontier Molecular Orbital (FMO) analysis, thermodynamic properties, dipole moments, and HOMO–LUMO energy were also computed. The calculated results show that the optimized geometry can well reproduce the crystal structure parameters, and the theoretical vibrational frequencies, 1H and 13C NMR chemical shifts and absorption wavelengths show good agreement with experimental values of the molecule.