Synthesis, characterization and thermal decomposition of bivalent transition metal alpha-hydroxyisobutyrates, M(C4H7O3)(2)center dot nH(2)O (M = Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II)), as well as the thermal behaviour of alpha-hydroxyisobutyric acid and its sodium salt were investigated employing simultaneous thermogravimetry and differential scanning calorimetry (TG-DSC), infrared spectroscopy (FTIR), TG-DSC coupled to FTIR, elemental analysis and complexometry. All the compounds were obtained as dihydrated, except the copper one which was obtained in the anhydrous state. The thermal decomposition of the anhydrous compounds occurs in a single or two steps and the final residue up to 235 degrees C (Mn), 300 degrees C (Fe), 305 degrees C (Co), 490 degrees C (Ni), 260 degrees C (Cu) and 430 degrees C (Zn) is Mn2O3, Fe2O3, Co3O4, NiO, CuO and ZnO, respectively. The results also provided information concerning the ligand's denticity and identification of the gaseous products evolved during the thermal decomposition of these compounds. (C) 2013 Elsevier B.V. All rights reserved.