Two Mononuclear Ni(II) and Cu(II) Complexes Containing a Bidentate Schiff Base Ligand: Syntheses, Structures and Antibacterial Activities

The title complexes, Ni(L)(2) (1) and Cu(L)(2) (2) based on HL (HL=N-(3-methylsalicylidene)tryptamine) have been synthesized under solvothermal conditions and characterized structurally by TGA, infrared spectra, elemental analysis and single-crystal X-ray diffraction. Complexes 1 and 2 both crystallize in monoclinic system, and the space groups are P2(1)/n with the unit cell parameters for complex 1: a=1.481 6(7) nm, b =1.310 0(6) nm, c=1.668 7(7) nm, beta=111.346(7)degrees, and for complex 2: a=1.479 7(2) nm, b=1.299 41(19) nm, c=1.667 6(2) nm, beta = 111.537(3)degrees. Complexes 1 and 2 possess the similar mononuclear structures, which are further extended into infinite 3D supramolecular frameworks by intramolecular C-H center dot center dot center dot O hydrogen bonds and intermolecular D-H center dot center dot center dot pi hydrogen bonds, respectively. Furthermore, the complexes and the ligand have been investigated for their preliminary antibacterial activities in detail by agar diffusion method, and the results demonstrate that complexes 1 and 2 display more excellent inhibiting effects than the ligand. CCDC: 1511747, 1; 1511743, 2.