Synthesis, characterization, electrochemical properties and conversions of carbon dioxide to cyclic carbonates mononuclear and multinuclear oxime complexes using as catalyst

Abstract

Abstract Unsymmetrical dioxime ligand and its mono- and multinuclear metal complexes were synthesized and characterized by 1 H and 13 C NMR spectra, FT-IR, UV–Vis, elemental analysis, melting point measurements, LC–MS spectroscopy, molar conductivity measurements and magnetic susceptibility and cyclic voltammetry techniques. We firstly prepared new unsymmetrical dioxime ligand ( 1 ) and its mononuclear [Ni(dioxime) 2 ] complex ( 2 ). Then, the intramolecular O−H⋯O bridges are replaced with Cu(II)(N–N) complex to synthesize multinuclear [Ni(dioxime) 2 Cu 2 (N–N) 2 ](ClO 4 ) 2 oxime complexes ( 3 – 7 ) where N–N = 2,2′-bipyridine (bpy), 1,10-phenanthroline (phen), 3,3′-dicarboxy-2,2′-bipyridine (dcbpy), 4,5-diazafluoren-9-one (dafo) and 1,10-phenanthroline-5,6-dione (dione). The mononuclear complex [Ni(dioxime) 2 ] ( 2 ) was used as a precursor for building multinuclear oxime complexes ( 3 – 7 ). In this paper, our goal is to study spectroscopic, electrochemical and catalytic properties of this new ligand and its metal complexes.