Synthesis, Characterization and Hirshfeld Surface Analysis of Some Thiosemicarbazones Containing a Five-Membered Ring

Thiosemicarbazones, which are multidentate ligands, are considered as one of the most important classes of organic compounds due to their broad spectrum of pharmacological effects and their ability to coordinate easily with metal ions. Four thiosemicarbazones, furan-2-carbaldehyde-N-methyl thiosemicarbazone ( Hfmtsc ), thiophene-2-acetaldehyde thiosemicarbazone ( Hattsc ), thiophene-2-acetaldehyde-N-methyl thiosemicarbazone ( Hatmtsc ) and thiophene-2-acetaldehyde-N-ethyl thiosemicarbazone ( Hatetsc ) were successfully prepared via condensation reaction using substituted aldehyde and (un)substituted thiosemicarbazides. They were characterized by melting point, elemental analysis, molar conductivity, FTIR, UV-Vis, 1 H and 13 C NMR spectroscopic techniques. The crystal structure of them was determined by using single crystal X-ray diffraction study. Intermolecular interactions were investigated by Hirshfeld surface analysis. Molecular structure of compounds was stabilized by N–H⋯S, C–H⋯S, N–H⋯O and C–H⋯O interactions. In each compound, the molecules are connected into dimers via pairs of N–H⋯S interactions.