Abstract
(4′-Amino-2′-methyl-5′-pyrimidinylmethylthio) acetic acid, Hamrapta, and the propionic acid analogue, Hammptp, and their copper(II), cobalt(II), zinc(II), palladium(II) and platinum(II) complexes have been synthesized. The pKa values of the acids (at 25°C) are 2.76 (Hammpta) and 2.74 (Hammptp). The complexes were characterized by microanalyses, IR and electronic spectra, conductivity and magnetic susceptibility measurements. While the zinc(II), palladium(II) and platinum(II) complexes exhibit tetrahedral and square-planar geometries, the copper(II) and cobalt(II) complexes exhibit a variety of geometries. One of the copper(II) complexes, [Cu(ammptp)ClH20], and one of the cobalt(II) complexes, [Co(Hammpta)2Cl2], are magnetically concentrated. [Co(Hammpta)2Cl2] is presumed to be low-spin octahedral or square-planar (μ = 2.18 B.M.), whereas the cobalt(II) complexes of Hammptp/ammptp are more prone to being tetrahedral.