A series of four-coordinate heteroleptic copper(I) complexes with diimine and β-diketiminate ligands

Abstract

In this paper, a series of heteroleptic bis-chelate copper(I) complexes of the general formula Cu(N^N)(NacNacR), where N^N is the diimine ligand and NacNacR is the β-diketiminate ligand are introduced. The complexes are easily prepared by reacting NacNac ligands with CuOtBu in the presence of diimine ligands. The molecular structures of all complexes are characterized by NMR spectroscopy and X-ray crystallography. The studies of cyclic voltammetry and UV–vis absorption spectra show that the HOMO and the LUMO energy level can be tailored by changing the substitution pattern of each ligand. The oxidation potential is dependent on the NacNac ligand, and the reduction potential shows the dependence on the diimine ligand. Tunable redox potentials and a wide range of visible absorption can make these copper(I) complexes promising candidates for applications in solar light harvesting.