Bridge, N-heterocyclic Carbene Complexes with Silver (I) and Palladium (II): Synthesis and Biological Activity

The present study describes synthesis, characterization (UV-Vis, FT-IR, 1HNMR, CHN analysis and melting point) and biological activity of new substituted benzimidazolium salt and their N-heterocycliccarbene (NHC) respective Ag(I) and Pd(II) complexes. The benzimidazole reacted with acetamide substituents at 90oC to form variety substituted of benzimidazolium salt to yield unsymmetrically substituted salt. Silver(I) complex was synthesized from the reaction of unsymmetrical substituted benzimidazolium salt with Ag₂O using in-situ deprotonation technique to give derived structures in good yield.The use of Ag(I)-NHC complex is as transfer reagents by using the transmetallation technique to prepare respective Pd(II)-NHC. The biological activity. of the formed substituted benzimidazolium salts, Ag(I) and Pd(II) complexes was estimated against some bacteria strains S. aureus. And E.coli. The Ag(I)showed good activity while their corresponding salt and Pd(II)-NHC complex show less activity.