Synthesis and theoretical studies of two new Co(III) and Cu(II) macroacyclic Schiff-base complexes containing piperazine moiety

The new Schiff base H2L1, has been prepared from the condensation of 2-hydroxybenzaldehyde with 2,2 -(piperazine-1,4-diylbis (methylene))dianiline (A). In the presence of appropriate metal ions and in methanolic/ethanolic solution two Cobalt (III) and Copper (II) macroacyclic Schiff-base complexes were prepared. the crystal structure of [CoL1](ClO4) complex have been revealed by single-crystal X-ray crystallography. The geometries of the [CoL1]+ and [CuL1] complexes have been optimized at the BP86/def2-SVP level of theory. Also the nature of the metal-ligand bond in the complexes is analyzed with NBO and EDA analysis