Synthesis,Characterization, and Structure of Metal(II) (-)-Sparteine Complexes Containing Acetate Ligands

The complexes Co(C₁₅H₂₆N₂)(C₂H₃O₂)₂] (1), Ni(C₁₅H₂₆N₂)(C₂H₃O₂)₂] (2), Cu(C₁₅H₂₆N₂)(C₂H₃O₂)₂] (3) and Zn(C₁₅H₂₆N₂)(C₂H₃O₂)₂] (4) were prepared from reaction of (?)-sparteine with the corresponding metal(II) acetates in ethanol at stoichiometric ligand to metal ratios. The complexes were characterized by UV-Vis and IR spectroscopies, and magnetic susceptibility measurements. The solid-state structures of 1, 2 and 4 have been determined by X-ray crystallography. The Complexes 1 and 2 display a pseudo-octahedral structure around the metal center, where two acetate ligands coordinate to the metal center in a bidentate fashion, whereas the metal centers in 3 and 4 adopt a pseudo-tetrahedral structure and two acetate ligands in these complexes coordinate to the metal center in a monodentate fashion. The whole set of prepared complexes has been used for comparative structural and spectroscopic studies.