Two Ni(ll) Complexes of Schiff Base Ligands Containing Benzimidazole Ring: Syntheses, Crystal Structures and Antibacterial Properties

Two complexes [Ni(L-1)(2)]center dot 2H(2)O (1) and [Ni(L-2)(2)]center dot 2H(2)O (2) have been synthesized using the bezimidazole derived tridentate (NNO donor) potential Schiff base ligands HL1 and HL2, which are prepared from reaction of 2-aminoethy1-1H-benzimidazole with 5-chlorosalicylaldehyde and 5-bromosalicylaldehyde, respectively, and characterized by elemental analysis, FT-IR and UV-Vis spectroscopies and single crystal X-ray crystallography. In 1 and 2, each Ni(II) has a distorted octahedral arrangement with a N4O2 donor set in trichelated fashion of the Schiff base ligands. Furthermore, the complex units in 1 and 2 are linked into 2D and 3D supramolecular networks by H-bonding in the solid state, respectively. The bioactivity studies showed that both the two complexes exhibit moderate to strong antibacterial activities against S. aureus (Gram-positive) and E. coli (Gram-negative) bacteria and were found more active than the corresponding Schiff base ligands. CCDC: 1401182, 1; 1401183. 2.