Non-covalent interactions abetted supramolecular arrangements of N-Substituted benzylidene acetohydrazide to direct its solid-state network

Abstract

Intra-molecular hydrogen bond modulation of compounds positively impacts their solubility, permeability and as well as potency in the field of medicinal chemistry. Herein, N-substituted benzylidene acetohydrazide derivative: (Z)-2-((6-chloropyridin-2-yl)oxy)-N'-(2-hydroxy-3-methoxybenzylidene)acetohydrazide (HOBAH), a novel solid state network was synthesized efficiently via sono-chemical approach. The structural characterization of HOBAH was achieved by single crystal analysis which exposed intra-molecular NH…O, OH…N bonding and intermolecular NH…O, OH…O and comparatively weak CH…O hydrogen bonding being responsible for the crystal packing. Theoretical calculations by applying the density functional theory (DFT) at DFT/B3LYP/6–311G(d,p) were completed. The characteristic of HOBAH was evaluated from a relaxed PES scan analysis and the HOBAH conformations with minimum energy have been identified. Hirshfeld surface (HS) and the quantum theory of atoms in molecules (QT-AIM) analyses bolstered in quantifying the existing non-covalent interactions. QT-AIM analysis unveiled that strong NH…O-H and CO…H-O hydrogen bonds (HBs) and other van der Waals interactions were responsible for the stabilization of these solid state networks. All non-covalent interactions with positive laplacian of electron density (∇2ρ) values from QT-AIM analysis corroborated well with the internal charge transfer and the hyper-conjugative interactions explored by NBO analysis. Moreover, all significant results were endorsed by both NPA and FMO evaluations. FMO analysis later assisted in the calculation of global reactivity indices. However, local reactivity indices were computed with Fukui function calculations. Lastly, molecular electrostatic potential (MEP) was plotted which confirmed the nucleophilic and electrophilic sites of HOBAH as elaborated by the reactivity indices.