Different intermolecular interactions in solvated and unsolvated isatin-based dithiocarbazate imine derivatives

The syntheses and structures of 2-fluoro-benzyl (<i>Z</i>)-2-(2-oxoindolin-3-yl-idene)hydrazine-1-carbodi-thio-ate dimethyl sulfoxide monosolvate, C₁₆H₁₂FN₃OS₂·C₂H₆OS (<b>1</b>) and 2-fluoro-benzyl (<i>Z</i>)-2-(5-bromo-2-oxoindolin-3-yl-idene)hydrazine-1-carbodi-thio-ate, C₁₆H₁₁BrFN₃OS₂ (<b>2</b>) are reported. Both structures feature a <i>Z</i>-configuration with respect to the C=N bond and the fluoro-benzyl ring is approximately orthogonal to the isatin moiety. For <b>1</b>, the crystal packing features weak C_ar-H⋯S (ar = aromatic) hydrogen bonds that link adjacent mol-ecules in a <i>C</i>(10) fashion to form pleated chains propagating along [001] and short S⋯O contacts between dimethyl sulfoxide solvent mol-ecules forming chains along [010]. The N-H hydrogen bond donors in <b>1</b> form either intra-molecular or discrete N-H⋯O_(DMSO) hydrogen bonds. In <b>2</b>, alternating <i>R</i> ² ₂(8)-type pairwise N-H⋯O hydrogen bonds and short F⋯Br contacts link the mol-ecules into chains propagating along [210]. The later unsolvated structure is of notably poorer quality and exhibits disorder in its <i>o</i>-fluoro-benzyl group, with a 180° flip and a small twist around the S-C bond. These findings are consistent with the results of Hirshfeld surface analyses.