Synthesis, Crystal Structures, and Preliminary Antibacterial Activities of Zinc(II) Complexes With a Tetradentate Schiff Base N,N′-Bis(1-pyridin-2-ylethylidene)propane-1,2- diamine

Two new mononuclear Schiff base zinc(II) complexes with the formula [ZnXL]·BF4 [X = Cl for (1) and X = Br for (2); L = N,N′-bis(1-pyridin-2-ylethylidene)propane-1,2-diamine] have been prepared. The complexes have been characterized by physicochemical methods and single-crystal X-ray determination. Each compound contains a mononuclear zinc(II) complex cation and a disordered fluoroborate anion. The zinc(II) atoms in both complexes are five-coordinated by the four N atoms of L, and by one halide atom, forming a square-pyramidal coordination. The Schiff base ligand and the zinc(II) complexes showed potent antibacterial activities.