Preparation, structure and antioxidant property of manganese(II) and zinc(II) complexes with bis(N-ethylbenzimidazol-2-ylmethyl)allylamine

Bis(N-ethylbenzimidazol-2-ylmethyl)allylamine (EtAIDB) and its two complexes, [Mn(EtAIDB)Cl-2] (1) and [Zn(EtAIDB)Cl-2] (2), have been synthesized and characterized by elemental analyses, molar conductivities, UV-Visible and IR spectra. The crystal structures of both complexes have been determined by X-ray single crystal diffraction. The coordination environment of Mn(II) in 1 is a five-coordinate distorted trigonal bipyramid with a N3Cl2 ligand set, while 2 is a four-coordinate twisted tetrahedral geometry. Structural and Hirshfeld surface analysis reveals that these two complexes are dimers formed by pi center dot center dot center dot pi interactions. The antioxidant activity was determined by superoxide methods in vitro, indicating that 1 exhibited potential antioxidant properties.