: Potentiometric and computational studies of Cobalt, nickel and copper complexes with bipyridyl and dl-2-amino-N-hydroxy-n-butanamide in aqueous solution
: Mohamed Ismael
: Volume 3 (2016)
: Equilibrium investigations of Co2+, Ni2+, Cu2+ complexes with mixed-ligand of 2,2’-bipyridyl (bipy) and Dl-2-amino N-hydroxy-n-butanamide (ahbt) were performed by potentiometric pH titrations in aqueous solution at room temperature and I = 0.5 mol/dm3 KCl. The obtained data were analyzed using the HYPERQUAD program. The results showed that the complexes has the molecular formula of [M(bipy)(H2ahbt)]3+, [M(bipy)(Hahbt)]2+, [M(bipy)(ahbt)]1+ and [M(bipy)(ahbt)H-1]. In the [M(bipy)(ahbt)]1+ species, the complexes were stabilized by forming five-member ring through the donation of the amino and hydroxomate nitrogens (Namino, Nhydroxom.) of ahbt and the two nitrogen atoms of bipy in the square planar geometry of the complex in basic solution. In the acidic and neutral solutions, protonated ahbt coordinates to [M(bipy)]2+ by the hydroxomate group forming a five- member ring with (O, O) donor atoms. In addition, 3D-structural geometry and electronic structures of Cu complexes were predicted using quantum mechanics calculations.