Structure and non-covalent interactions of (E,Z)3-benzoyl-1,5-bis(4-ethoxyphenyl)formazan: A Crystallographic and DFT/TD-DFT study

• Published in: Journal of molecular structure 2022-10, Vol.1266, p.133501, Article 133501
• Main Authors: K, Rajeena C, C, Sumayya P, T, Shalina Begum, Kb, Muraleedharan
• Format: Article
• Language: English
• Subjects: Crystal structure; Density Functional Theory; Formazan; Hirshfeld surface analysis; Intermolecular interaction energy; π– π stacking
• ISSN: 0022-2860; 1872-8014
• DOI: 10.1016/j.molstruc.2022.133501

•The formazan derivative is characterized by spectroscopic and SCXRD methods.•The experimental and theoretical spectroscopic studies are carried out.•Hirshfeld surface analysis and fingerprint plots are recorded.•MEPS studies predicted sites for electrophilic/ nucleophilic attack.•Energy-framework diagrams showed interactions are mostly dispersion in nature. Formazans, an important class of compounds are known for their intense color and high complexing capability. Herein we report the synthesis and structure of 3-benzoyl-1,5-bis(4-ethoxyphenyl)formazan, compound 1 along with the detailed analysis of non-covalent interactions in its crystalline state. The chemical structure of compound 1 was characterized using various spectroscopic techniques and single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic, P 21/c space group with a single molecule in the asymmetric unit. The molecular structure of 1 was further investigated using DFT/TD-DFT methods at the CAM-B3LYP/6-31+G (d, p) level of theory. The ground state geometrical parameters along with NMR, vibrational and electronic absorption spectra calculated are in accordance with the experimental data. The spectral and theoretical results revealed that compound 1 exists as amine-imine tautomeric forms. Hirshfeld surface and fingerprint analysis were employed to explore the surface characteristics of the molecules in the crystal. Hirshfeld surface studies reflected that the molecular arrangement in the crystal is stabilized by various intermolecular interactions such as hydrogen bonding and π - π stacking. Among various interactions, the dispersion forces play a dominant role in crystal packing as evident from the molecular interaction energy calculations. The compound, 3-benzoyl-1,5-bis(4-ethoxyphenyl)formazan exhibits amine-imine tautomerism through strong N4H4…N1 hydrogen bonding. The molecule possesses potential C19H19…O5 intermolecular interactions as evident from SCXRD and DFT studies [Display omitted] .