Electrocatalytic oxygen evolution and antiproliferative activity of Co(III) complexes stabilized by in situ generated bis(5‐furan/phenyl‐1,2,4‐triazole)‐3‐sulfinamide

Abstract

Electrocatalytic water oxidation by transition metal complexes is an emerging area of research. Here, two cobalt(III) complexes [Co(ftsm)NH3(o‐phen)]·H2O (1) {ftsm = bis(5‐furan‐1,2,4‐triazole)‐3‐sulfinamide} and [Co(ptsm)NH3(o‐phen)]·CH3OH (2) {ptsm = bis(5‐phenyl‐1,2,4‐triazole)‐3‐sulfinamide} were synthesized and characterized by various spectroscopic and X‐ray crystallography techniques. Complexes 1 and 2 were found to have admirable electrocatalytic activity towards oxygen evolution reaction (OER). The Tafel slope values for GC/Nf‐Complex‐2 and GC/RuO2 were 53 and 60 mV/dec, respectively. Consequently, complex 2 possesses a better water oxidation response than standard material RuO2. The ligands Haftt, Haptt, o‐phen, and complexes 1 and 2 were also tested for their cytotoxicity against Dalton's lymphoma (DL) cells employing MTT assay and found to have significant cytotoxicity. The IC50 values of Haftt, Haptt, mixed ligands Haftt + o‐phen and Haptt + o‐phen, and complexes 1 and 2 against DL cells were found to be 150, 400, 200, 450, 80, and 5 μM, respectively. The complexes were found to have minimal effect on normal cells. The remarkable IC50 value for complex 2 shows that it can be utilized as a potential anticancer agent against DL cells.