Synthesis and Characterization of Ortho-Halogen-Substituted Mono- and Bisthiocarbohydrazones: Structural Comparison

Six ortho-substituted halogen derivatives (F, Cl, Br) of mono- and analog bisthiocarbohydrazones were synthesized and fully characterized. Structural characterization was performed through elemental analysis and NMR, FT-IR and UV-Vis spectroscopy. Also, all compounds were successfully isolated in the form of single crystals, and X-ray analysis was applied. Through the comparative structural analysis, similarities and differences of the mono- and bisubstituted derivatives were discussed on the molecular level, but also in terms of crystal packing. Special focus was on the assessment of the influence of the additional condensation and intramolecular interactions on molecular geometry and supramolecular organization. In addition, thermal properties of all compounds were analyzed, and for monosubstituted derivatives, ionization constants of the terminal amino group were determined.