Spectroscopic and electrochemical study of dinuclear and mononuclear copper complexes with the bidentate ligand of the 2,2′-diquinoline series

Abstract

The newly synthesized complex (2) of copper(I) chloride with di n hexyl 2,2´ biquinoline 4,4´ dicarboxylate (L) was spectroscopically and electrochemically characterized. The X ray diffraction study showed that the crystals of complex 2 consist of the dinuclear moieties [L 2 Cu I 2 (μ Cl) 2 ] containing Cu 2 (μ Cl) 2 clusters. Spectrophotometric studies and ESI mass spec trometric measurements showed that after the dissolution of complex 2 in acetonitrile (AN) and N methyl 2 pyrrolidone (NMP), the solution contained not only the dinuclear complexes [L 2 Cu I 2 (μ Cl) 2 ] but also [L 2 Cu I ]Cl, [LCu I Cl(Sol)], and [Cu I Cl(Sol)] (Sol is the solvent). The electrochemical data also confirm the conclusion that bridged dinuclear chloride complex 2 dissociates both in NMP and AN to form the tetrahedral bis biquinoline complex [L 2 Cu I ]Cl. In solutions of complex 2 in alcohols and N,N dimethylformamide (DMF), only [L 2 Cu I ]Cl and [Cu I Cl(Sol)] are present. In EtOH, AN, and DMF, [Cu I Cl(Sol)] undergoes disproportionation to [Cu II Cl(Sol)] and Cu 0 .

Di-μ-iodido-bis[(dimethyl 2,2′-biquinoline-4,4′-dicarboxylate-κ2 N,N′)copper(I)]

“…Copper(I) complexes are a subject of high interest and have been extensively studied during the past two decades because of their diversified photo-physical properties (Lavie-Cambot et al, 2008;Vorontsov et al, 2009;Hashimoto et al, 2011). The title complex is similar to other copper(I) complexes with halides and aromatic diimines: [Cu 2 I 2 (1,10-phenanthroline) 2 ] and Cu 2 X 2 (2,9-dimethyl-1,10-phenanthroline) 2 ], where X = I, Br, Cl (Healy et al, 1985); [Cu 2 X 2 (1,10-phenanthroline) 2 ], where X = Cl and I (Yu et al, 2004); [Cu 2 X 2 (NN) 2 ], where X = Br, I and NN = bidentate imino nitroxides (Oshio et al, 1996) (Vatsadze et al, 2010). For the preparation of the dimethyl-2,2 0 -biquinoline-4,4 0 -dicarboxylate ligand, see: Pucci et al (2011) and of the P(CH 2 N(CH 2 CH 2 ) 2 O) 3 phosphane ligand, see: Starosta et al (2010).…”

Synthesis, crystal structure and Hirshfeld surface analysis of di-μ2-iodido-bis[(2,2′-biquinoline-κ2 N,N′)copper(I)]

“…Copper(I) bypiridine complexes are of interest because of their structural peculiarities, cuprophilic interactions, and important photochemical properties. Therefore, bypyridine-type systems are often the ligands of choice to explore new metal complexes with potentially useful properties (Ferraro et al, 2022;Starosta et al, 2012;Vatsadze et al, 2010). 2,2 0 -Biquinoline is an important and widely employed diimine ligand.…”

“…All compounds crystallize in the triclinic space group P1. In IRIVIP (Vatsadze et al, 2010), n-hexyl carboxylate groups are attached to the quinoline rings at position 4. In YIJFAA, YIJFEE, and YIJFII (Sun et al, 2013), ethyl carboxylate fragments are attached, and in PAYKIL (Starosta et al, 2012), there are methyl carboxylate fragments.…”

Investigation of a copper(i) biquinoline complex for application in dye-sensitized solar cells

“…The peak oxidation potential, E ox p , was +0.78 V and the peak reduction potential, E red p , was +0.33 V. Vatsadze et al reported the electrochemistry of the similar complex [CuL 2 ][Cl] where L ¼ di-nhexyl 2,2 0 -biquinoline-4,4 0 -dicarboxylate. 44 The Cu(I) to (II) oxidation occurred at E ox p ¼ +0.74 V versus Ag/AgCl (sat. KCl), which is in good agreement with our ndings.…”