Synthesis and characterization of tin(II) complexes of fluorinated Schiff bases derived from amino acids

New tin(II) complexes of general formula Sn(L)2 (L = monoanion of 3-methyl-4-fluoro-acetophenone phenylalanine L1H, 3-methyl-4-fluoro-acetophenone alanine L2H, 3-methyl-4-fluoro acetophenone tryptophan L3H, 3-methyl-4-fluoro-acetophenone valine L4H, 3-methyl-4-fluoro-acetophenone isoleucine L5H and 3-methyl-4-fluoro-acetophenone glycine L6H) have been prepared. It is characterized by elemental analyses, molar conductance measurements and molecular weight determinations. Bonding of these complexes is discussed in terms of their UV–visible, infrared, and nuclear magnetic resonance (1H, 13C, 19F and 119Sn NMR) spectral studies. The ligands act as bidentate towards metal ions, via the azomethine nitrogen and deprotonated oxygen of the respective amino acid. Elemental analyses and NMR spectral data of the ligands with their tin(II) complexes agree with their proposed square pyramidal structures. A few representative ligands and their tin complexes have been screened for their antibacterial activities and found to be quite active in this respect.