Mixed-ligand complex formation in the copper(I)-2,9-dimethyl-1,10-phenanthroline-3,3′-bonded biquinoline system according to 1H NMR data

Abstract

The reaction of the copper(I) 2,9-dimethyl-1,10-phenanthroline (neocuproine, DMP) complex with 2,3,8,9-dibenzo-4,7-dimethyl-5,6-dihydro-1,10-phenanthroline (cuprotest, DMQ) in a CD3OD solution has been studied by 1H NMR spectroscopy. The substitution of DMQ for the DMP liqand in the inner coordination sphere of the Cu+ complex has been observed. A model of the process including the formation of a mixed-ligand complex, presumably of bridged structure, is proposed to describe the observed experimental dependences of integrated intensities of the NMR signals in the spectrum on the concentrations of the components of the solution.