Crystal structure analysis of (E)‐N‐(3, 5‐dimethylphenyl)‐2‐(substituted benzylidene)thiosemicarbazone: Experimental and theoretical studies. (21st September 2020)

• Record Type: Journal Article
• Authors: Wang, Sifan; Zhang, Xing; Qi, Fan; Huang, Jie; Wei, Chenli; Guo, Zeyu
• Is Part Of: Journal of physical organic chemistry. Volume 34:Number 2(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-09-21
• Subjects: crystal structure -- quantum chemical calculations -- RDG function -- thiosemicarbazone -- UV‐visible spectroscopy; Chemistry, Physical organic -- Periodicals; 547.1
• DOI: 10.1002/poc.4138
• Languages: English
• ISSNs: 0894-3230

Abstract

Abstract: Two novel thiosemicarbazone derivatives ( E )‐ N ‐(3, 5‐dimethylphenyl)‐2‐(3‐methylbenzylidene)thiosemicar‐bazone (1 ) and ( E )‐ N ‐(3, 5‐dimethylphenyl)‐2‐(3‐fluorobenzylidene)thiosemicarbazone (2 ) had been synthesized and characterized by FT‐IR, nuclear magnetic resonance, and elemental analysis. Single crystal X‐ray diffraction analysis showed that compound 1 belongs to triclinic system in P‐1 space group and compound 2 belongs to monoclinic system in C2/c space group. It could be seen from the determined crystal structure that the central skeleton NNHC(S)NH of both thiosemicarbazone compounds have good planarity. Density functional theory (DFT) calculations were done using B3LYP/6‐31+G(d, p) basis set and the calculated results are in good agreement with the experimental data. In addition, the UV‐visible absorption spectrum was estimated based on TD‐DFT quantum chemistry calculations. Likewise, the simulated absorption spectrum is very consistent with the experimental data. Combining Hirshfeld surface analysis and molecular structure, it was found that the intermolecular hydrogen bond NH···SC constitutes central symmetric dimer S 2 2 8 . Through quantum chemical calculation, we investigated the reduced density gradient function and the independent gradient model, which provided a deeper insight into the intermolecular and intramolecular interaction force of the compounds. The frontier molecular orbital analysis and molecular electrostatic potential were also discussed by theoretical calculations. Abstract : A series of novel thiosemicarbazone derivative ( E )‐ N ‐(3, 5‐dimethylphenyl)‐2‐(3‐methylbenzylidene)thios emicarbazone have been synthesized and characterized. The differences of intermolecular hydrogen bonds and their interactions contribute to the crystal packing by Hirshfeld surfaces, the reduced density gradient function and the Independent Gradient Model analysis. UV‐vis spectroscopy, Various chemical properties, the frontier molecular orbital (FMO) and molecular electrostatic potential (MEP) of these title compounds are also investigated by theoretical calculations.