Mononuclear Schiff Base Complexes Derived from 5-Azophenylsalicylaldehyde with Co(II), Ni(II) Ions: Synthesis, Characterization, Electrochemical Study and Antibacterial Properties

Abstract

In the present research, 1,2-di[N-2-phenylthio-5-azophenylsalicylidene]ethane (H 2 L 1), 1,3-di[N-2-phenylthio-5-azophenylsalicylidene]propane(H 2 L 2) and 1,4-di[N-2-phenylthio-5-azophenylsalicylidene]butane (H 2 L 3) were synthesized. ML 1 , ML 2 and ML 3 complexes were prepared through the reaction of H 2 L 1 , H 2 L 2 and H 2 L 3 with Ni(II) and Co(II) acetate salts. The prepared ligands and their complexes were characterized with FT-IR, 1 H-NMR, elemental analysis, conductivity and magnetic measurements, ESI-mass, UV-Vis spectroscopy and cyclic voltammetry. The complexes had monomeric structure according to the mass spectral data. All of the complexes had a six-coordinated octahedral geometry. The electrochemical behavior of the ligands, Ni(II) and Co(II) complexes was investigated by CV in DMF under argon atmosphere. The results show that the coordination of Ni(II) causes the ligands to be deactivated. The voltammogram of Co(II) complexes shows that the reduction of CoL 1 is harder than CoL 3 and CoL 2 is inactive. Their antibacterial activity was investigated and the complexes exhibited better antibacterial activity than the free ligands against selective bacteria.

A new β-cyclodextrin-based nickel as green and water-soluble supramolecular catalysts for aqueous Suzuki reaction

“…Recently, great concentration has been expended on using nickel as a popular option for substitute Pd in cross-coupling reactions 18 – 27 . It is known that nickel has a lower price, heightened reactivity, is more abundant, and can be used in many organic reactions 28 – 37 . The nickel-catalyzed Suzuki reaction has a mechanism similar to that of palladium 38 .…”

Spectral Analysis and In vitro Biological Activity of Cu(II) Complex with Tridentate ONO Schiff Base Ligand

“…Although the Schiff bases are known to be good chelating agents, and easily prepared and characterized, little interest has been given to their uses for analytical purposes because of two serious drawbacks, they are insoluble in aqueous solutions and they decompose easily in acidic solutions, limiting their use to basic conditions [5]. Schiff bases and its metal complexes also exhibit a wide variety of biological activities, including antifungal, antibacterial, antitumor, anti-inflammatory, trypanocidal, anti-HIV, antimalarial, and anti-urease activities [6][7][8][9][10][11][12][13][14][15][16]. The imine group present in these compounds is critical for their biological activities, and thus that moiety has been extensively explored for the development of new bioactive substances [6].…”