Structural Characterization, DFT, Hirshfeld Surface Analysis and Antibacterial Activity of a Schiff Base Derived from Cyclohexanediamine

• Published in: Journal of molecular structure Vol. 1232; p. 130066
• Main Authors: Nasaruddin, Nur Husnina, Ahmad, Shahrul Nizam, Sirat, Siti Syaida, Wai, Tan Kong, Zakaria, Nurul Aili, Bahron, Hadariah
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.05.2021
• Subjects: crystal structure; DFT calculations; Hirshfeld surface analysis; Schiff base; Schiff base; crystal structure; Hirshfeld surface analysis; DFT calculations
• ISSN: 0022-2860; 1872-8014
• DOI: 10.1016/j.molstruc.2021.130066

•Synthesis and characterization of a Schiff base, AD2Me, are reported.•Molecular structure is confirmed through x-ray crystallography.•DFT analysis on frontier molecular orbital revealed a large HOMO-LUMO energy gap.•Hirshfeld analysis revealed dominant C•••H and H•••H intermolecular interactions.•No significant bactericidal activity against ATCC 6538 and ATCC 700610. A new Schiff base derived from cyclohexanediamine and 3-methylsalicylaldehyde was obtained. The Schiff base, 6,6′-((1E,1′E)-(cyclohexane-1,2-diylbis(azanylylidene))bis(methanylylidene))bis(2-methylphenol), (AD2Me) was characterized through elemental analysis, infrared, UV-Vis, 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. The structure of the grown crystal was elucidated by using single crystal X-ray diffraction technique. The compound crystallized in the triclinic system, P-1 space group. The cell length and volume for AD2Me are a = 10.4582(11) Å, b =10.8141(9) Å, c =18.7472(14) Å, α = 90.629(7)°, β = 92.444(7)°, γ = 109.561(9)° and V =1995.3(3) Å3, respectively. The crystal structure is stabilized by intramolecular hydrogen bond O˗H•••N and intermolecular hydrogen bonds C˗H•••O, C˗H•••π and π•••π. The B3LYP method was used to calculate the optimized structure of the molecule through density functional theory (DFT) using the 6-311G++(d, p) basis set and the results of the conformation analysis was in good agreement with the crystal structure determined by x-ray single crystal diffraction. Additionally, the molecular electrostatic potential, frontier molecular orbitals and chemical reactivity descriptors of AD2Me were further investigated using DFT, revealing the electronic properties of the compound. A Hirshfeld surface analysis was performed to analyze intermolecular interactions in the crystal structure. The compound showed no significant activity against Staphylococcus aureus subsp. aureus Rosenbach (ATCC 6538) and Streptococcus mutans Clarke (ATCC 700610). [Display omitted]