The synthesis and crystal structure of (E)-2-{[(4-methoxynaphthalen-1-yl)methylidene]amino}-4-methylphenol: Hirshfeld surface analysis, DFT calculations and anticorrosion studies.

Abstract

The title Schiff base compound, (E)-2-{[(4-methoxynaphthalen-1-yl)methylidene]amino}-4-methylphenol, C₁₉H₁₇NO₂ (I), was synthesized via the reaction of 2-amino-4-methylphenol with 4-methoxynaphthalene-1-carbaldehyde. The structure of I was characterized by NMR, IR and UV-Vis spectroscopies in different solvents. The interatomic contacts in the crystal structure were explored using Hirshfeld surface analysis, which, together with the two-dimensional fingerprint plots, confirm the predominance of dispersion forces in the crystal structure. The molecule of I has a twisted conformation, with the mean plane of the naphthalene ring system being inclined to the plane of the phenol ring by 33.41 (4)°. In the crystal, molecules are linked by C-H...O hydrogen bonds to form inversion dimers. There are parallel-displaced π-π interactions present, together with C-H...π interactions, resulting in the formation of a three-dimensional structure. The anticorrosion potential of I was also investigated using density functional theory (DFT) in the gas phase and in various solvents. The compound was shown to exhibit significant anticorrosion properties for iron and copper. The molecular structure of I was determined by DFT calculations at the M062X/6-311+g(d) level of theory and compared with the crystallographically determined structure. Local and global reactivity descriptors were computed to predict the reactivity of I. Excellent agreement was observed between the calculated results and the experimental data.