Crystal structure, Hirshfeld surface analysis and DFT studies of (E)-4-methyl-2-{[(2-methyl-3-nitrophenyl)imino]methyl}phenol

The title compound, C15H14N2O3, was prepared by condensation of 2-hydroxy-5-methyl-benzaldehyde and 2-methyl-3-nitro-phenylamine in ethanol. The configuration of the C=N bond is E. An intramolecular O—H...N hydrogen bond is present, forming an S(6) ring motif and inducing the phenol ring and the Schiff base to be nearly coplanar [C—C—N—C torsion angle of 178.53 (13)°]. In the crystal, molecules are linked by C—H...O interactions, forming chains along the b-axis direction. The Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H...H (37.2%), C...H (30.7%) and O...H (24.9%) interactions. The gas phase density functional theory (DFT) optimized structure at the B3LYP/ 6–311 G(d,p) level is compared to the experimentally determined molecular structure in the solid state. The HOMO–LUMO behaviour was elucidated to determine the energy gap.