2-{(1E)-[(E)-2-(2,6-Dichlorobenzylidene)hydrazin-1-ylidene]methyl}phenol: crystal structure, Hirshfeld surface analysis and computational study

Abstract

The title Schiff base compound, C14H10Cl2N2O, features an E configuration about each of the C=N imine bonds. Overall, the molecule is approximately planar with the dihedral angle between the central C2N2 residue (r.m.s. deviation = 0.0371 Å) and the peripheral hydroxybenzene and chlorobenzene rings being 4.9 (3) and 7.5 (3)°, respectively. Nevertheless, a small twist is evident about the central N—N bond [the C—N—N—C torsion angle = −172.7 (2)°]. An intramolecular hydroxy-O—H...N(imine) hydrogen bond closes an S(6) loop. In the crystal, π–π stacking interactions between hydroxy- and chlorobenzene rings [inter-centroid separation = 3.6939 (13) Å] lead to a helical supramolecular chain propagating along the b-axis direction; the chains pack without directional interactions between them. The calculated Hirshfeld surfaces point to the importance of H...H and Cl...H/H...Cl contacts to the overall surface, each contributing approximately 29% of all contacts. However, of these only Cl...H contacts occur at separations less than the sum of the van der Waals radii. The aforementioned π–π stacking interactions contribute 12.0% to the overall surface contacts. The calculation of the interaction energies in the crystal indicates significant contributions from the dispersion term.

Keywords

• crystal structure
• Schiff base
• Hirshfeld surface analysis
• computational chemistry