Synthesis and characterization of Cu (II), Co (II), Ni (II), Au (III), complexes with (Z)-1-(4-((3-chlorobenzylidene) amino)phenyl)ethan-1-one ligand

Abstract

Schiff bases are considered privileged ligands, as condensation between aldehydes and amines makes them easy to prepare also in the synthetic design, stereogenic centers, or other chirality elements can be introduced. Schiff base ligands can combine and stabilize with several different metals in different oxidation states, allowing Schiff base metal complexes to be used for a wide range of useful catalytic transformations. The reaction in ethanol of 4-aminoacetophenoneand 3-chlorobenzaldehyde resulted in the formation of Schiff base (Z)-1-(4-((3-chloro benzylidene)amino)phenyl)ethan-1-one. Ligand contact with different di- and trivalent metal ions were observed and ligand complexes are prepared from the reaction of two ligand (Z)-1-(4-(3-chlorobenzylidene) amino) phenyl) ethan-1-one equivalents with one mole of metal salt as the central ion. Physicochemical and spectroscopic methods were put in place to confirm bonding mode and over all complex structure. These results lead to the preparation of four coordinate complexes, and we suggested the structure of the complexes from the above discussions is tetrahedral except Au complex which is square planar geometry. IR, UV, NMR, mass, conductivity, elemental study, and magnetic susceptibility characterized the ligand and its complexes. Materials and Methods: The reaction in ethanol of 4-aminoacetophenone and 3-chlorobenzaldehyde with molar ratio (1:1) in absolute ethanol with just a few drops of acetic acid resulted in the formation of Schiff base (Z)-1-(4-((3-chlorobenzylidene)amino) phenyl) ethan-1-one. Results: The complexes were prepared from the reaction of the ligand L with metal chloride salts (M) in a 2:1 mole ratio heated under reflux in ethanol, where M= Co+2, Ni+2, Cu+2, and Au+3. IR, UV, NMR, mass, conductivity, elemental study, and magnetic susceptibility characterized the ligand and its complexes. These results lead to the preparation of four coordinate complexes: [Co(L)2(Cl)2], [Cu(L)2(Cl)2], [Ni(L)2(Cl)2], and [Au(L)2(Cl)2]Cl. Conclusion: we concluded that the structure of the complexes from the physicochemical and spectroscopic methods is tetrahedral except the Au+3 complex which is square planar geometry