Reactivity of mercury(II) halides with the α-keto stabilized sulfonium ylides: Crystal structures of two new polymer and binuclear complexes and in vitro antibacterial study

Reaction of α-keto stabilized sulfonium ylides (Me)2SCHC(O)C6H4R (R = p-NO2 (Y) and p-Br(Y′)) with HgX2 (X = Cl, Br and I) in equimolar ratios using methanol as solvent leads to two types of products. Single crystal X-ray diffraction analysis reveals (i) binuclear complex of [HgI2(Y)]2 (3) with an asymmetric halide-bridged structure and (ii) one-dimensional polymer of [HgI2(Y′)]n (6) that the monomeric –Hg–I–Hg– bridging leads to a zig-zag polymeric chain in which mercury assumes a distorted tetrahedral geometry. Characterization of the compounds by IR, 1H and 13C NMR spectroscopy confirmed coordination of the ylide to the metal through the carbon atom. Analytical data indicate a 1:1 stoichiometry between the ylide and Hg(II) halide in all of products. The Hg(II) complexes with different ligands evaluated for their antibacterial activity using disc diffusion method. The results show that all complexes represent antibacterial activity against bacteria tested especially on Gram positive ones.

Reaction of α-keto stabilized sulfonium ylides (Me)2SCHC(O)C6H4R (R = p-NO2 and p-Br) with HgX2 (X = Cl, Br and I) leads to binuclear and polymer products of the type [HgX2(Ylide)]2 and [{HgI(Ylide)]n. The infrared, NMR data and the X-ray crystal structures of the complexes 1 and 2 demonstrate C-coordination of the ylide to the metal and presence of the asymmetric halide-bridged binuclear and the zig-zag polymeric chain structures, respectively. In addition, the antibacterial effects of the DMSO-solutions of the complexes were investigated by disc diffusion method against three Gram positive and three negative bacteria.Figure optionsDownload as PowerPoint slide