Crystal structure and Hirshfeld surface analysis of dimethyl 3,3′-{[(1E,2E)-ethane-1,2-diyl­idene]bis(aza­nylyl­idene)}bis­(4-methyl­benzoate)

The title Schiff base compound, C20H20N2O4, synthesized by the condensation reaction of methyl 3-amino-4-methyl­benzoat and glyoxal in ethanol, crystallizes in the the monoclinic space group P21/n. The mol­ecule is Z-shaped with the C—N—C—C torsion angle being 47.58 (18)°. In the crystal, pairs of mol­ecules are linked via C—H⋯N hydrogen bonds, forming centrosymetric dimers with an R22(8) ring motif; this connectivity leads to the formation of columns running along the a-axis direction. Hirshfeld surface analysis and two-dimensional fingerprint plots were used to explore the inter­molecular inter­actions and revealed that the most significant contributions to the crystal packing are from H⋯H (49.4%), H⋯O/O⋯H (19.0%) and H⋯C/C⋯H (17.5%) contacts. Energy frameworks were constructed through different inter­molecular inter­action energies to investigate the stability of the compound. The net inter­action energies for the title compound were found to be electrostatic (Eele = −48.4 kJ mol−1), polarization (Epol = −9.7 kJ mol−1), dispersion (Edis = −186.9 kJ mol−1) and repulsion (Erep = 94.9 kJ mol−1) with a total inter­action energy, Etot, of −162.4 kJ mol−1.