Antioxidant potential and secondary reactivity of bis{diphenyl(2-pyridyl)phosphino}copper(II) complex

Abstract

Copper-based complexes with the general formulas lbrack $Cu{(L)}_2;rbrack Cl_2$ (1) and $lbrack Cu_2;L_2;(µ_2-L)µ_2-;Cl_2;rbrack$ (2) anda mixed-ligand anionic complex [Cu(L) 2 dedtc][LCl] (3b), where L = diphenyl(2-pyridyl)phosphine and dedtc = diethyldithiocarbamate, were synthesized and structurally characterized. X-ray analysis revealed that the coordinationenvironment around the copper atom in complexes 1–3 is distorted tetrahedral. In monomeric complexes 1 and 3bboth diphenyl(2-pyridyl) phosphine ligands are monodentate and are coordinated through the P-atom. In complex 3btwo phosphine ligands are attached to copper through the P-atom. The third phosphine ligand acts as a bridged ligand,coordinated to the metal centers through the P-atom and N-atom. Complexes 1 and 3b were tested for radical scavenging activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) as a free radical. A prominent color change after mixing thesolution of complex 1 and DPPH was observed, indicating the efficiency of the compound as antioxidant.