Crystal structure, optical properties and electrochemiluminescence of Cu(I), Ag(I) and Au(I) complexes that contain the cyanoacetic acid triphenylamine ligand

A series of novel metal complexes, [Cu-2(dppm)(2)(OOCL)](2)[NO3](2) (1), [Ag-2(dppm)(2)(OOCL)(2)] (2) and [Au-2(dppm)(2)(OOCL)(2)] (3) (dppm = bis(diphenylphosphino)methane, L = 2-cyano-3-(4-(diphenylamino) phenyl)acrylic acid) were prepared and structurally characterized by X-ray crystallography. Their optical properties were investigated by absorption and fluorescence spectra. The fluorescence spectra of the complexes showed red shifts relative to that of L, which exhibited the same tendency as the absorption spectra. In addition, the ability of 1-3 to generate electrochemiluminescence (ECL) were assessed in acetonitrile solutions, they exhibited a highly enhanced stable ECL emission compared to the free ligand (L). Especially, the ECL intensity of 1 was approximately 30 times greater than that of L. (C) 2015 Elsevier Ltd. All rights reserved.