Methylmercury and dimethylthallium complexes of 5-(4′-dimethylaminobenzylidene)-2-thiohydantoin (HDABTd): The crystal and molecular structures of HDABTd and [TlMe 2(DABTd)(DMSO)

Abstract

The ligand 5-(4′-dimethylaminobenzylidene)-2-thiohydantoin (HDABTd) was prepared and its structure determined by X-ray diffraction. In the crystal, ligand molecules are linked in chains along the [110] direction by intermolecular N(3)–H(3)⋯O(1) I and N(1)–H(1)⋯S ii hydrogen bonds. The complexes [HgMe(DABTd)] and [TlMe 2(DABTd)] were prepared by reaction of the ligand with methylmercury acetate or dimethylthallium hydroxide, and were characterized in the solid state by IR spectroscopy and in solution by conductivity measurements and 1H, 13C, 199Hg and 205Tl NMR spectroscopy. The dimethylthallium complex crystallized in DMSO solution as [TlMe 2(DABTd)(DMSO)], an X-ray diffraction study of which showed its thallium atoms to be coordinated to the two methyl C atoms, the oxygen atom of a DMSO molecule, the S and N(1) atoms of one DABTd ligand and, more weakly, to the oxygen atom of a neighbouring DABTd. This last interaction links the molecules of the complex in chains parallel to the b axis. Crystals of the methylmercury(II) complex contain three [HgMe(DABTd)]·DMSO structures per asymmetric unit, but poor data quality prevented complete refinement.