A novel 3-acetoxy-2-methyl-N-(4-methoxyphenyl)benzamide: Molecular structural describe, antioxidant activity with use X-ray diffractions and DFT calculations

Abstract In this work, the structure of a novel 3-acetoxy-2-methyl- N -(4-methoxyphenyl) benzamide, was analyzed both experimentally and theoretically using three methods, X-ray single crystal diffraction technique, IR spectroscopy, and quantum chemical computation. The X-ray diffraction analysis indicates that 3-acetoxy-2-methyl- N -(4-methoxyphenyl) benzamide molecula crystallizes in a triclinic system (space group P−1) and the calculated lattice constants are, a = 5.1205 ± 0.0004 A, b = 9.8598 ± 0.0008 A, c = 15.3398 ± 0.0013 A, α  = 80.79(7)°, β  = 83.142(6)°, γ = 85.411(6)°, and Z = 2. In addition, the molecular geometry and vibrational frequencies of the title compound in ground state have been calculated using density functional theory (DFT) at B3LYP level 6-31G+(d,p) basis set. The geometrical parameters of the title compound obtained from XRD studies are good in agreement with the calculated values. The electronic properties, such as HOMO and LUMO energies and thermodynamic properties were calculated with DFT (using B3LYP/6-31G+(d,p) basis set) approach. To estimate the chemical reactivity of the molecule, the molecular electrostatic potential (MEP) surface map of the title molecule and PES scan were investigated with theoretical calculations at the B3LYP/6-31+G(d,p) and B3LYP/3-21G levels, respectively. Antioxidant properties are determined using DPPH free radical scavenging test.