Cobalt(III) and nickel(II) complexes with 3-hydroxyamino-3-methylbutan-2-one thiosemicarbazone: Synthesis and structures

Condensation of 3-hydroxyamino-3-methylbutan-2-one with thiosemicarbazide afforded 3-hydroxyamino-3-methylbutan-2-one thiosemicarbazone as a new ligand (H2L). Cobalt(III) and nickel(II) complexes with this ligand were obtained. The molecular formulas and structures of the thiosemicarbazone and the complexes [Co(HL)(2)]Cl center dot 2H(2)O (I) and [Ni(H2L)(2)]Cl-2 center dot 2.25H(2)O (II) were confirmed by elemental analysis, IR spectroscopy, and X-ray diffraction (CIF files CCDC nos. 985065 (H2L), 985066 (I), and 985067 (II)). The crystal structures of the ligand H2L and complexes I and II were determined. The way in which the ligand is coordinated to the metal ions, its conformational changes upon the complexation, and the packing patterns in the crystals of H2L, I, and II are discussed.