Jump to main content
Jump to site search

Issue 40, 2018
Previous Article Next Article

Luminescent copper(i) complexes with bisphosphane and halogen-substituted 2,2′-bipyridine ligands

Author affiliations


Heteroleptic [Cu(P^P)(N^N)][PF6] complexes, where N^N is a halo-substituted 2,2′-bipyridine (bpy) and P^P is either bis(2-(diphenylphosphino)phenyl)ether (POP) or 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (xantphos) have been synthesized and investigated. To stabilize the tetrahedral geometry of the copper(I) complexes, the steric demands of the bpy ligands have been increased by introducing 6- or 6,6′-halo-substituents in 6,6′-dichloro-2,2′-bipyridine (6,6′-Cl2bpy), 6-bromo-2,2′-bipyridine (6-Brbpy) and 6,6′-dibromo-2,2′-bipyridine (6,6′-Br2bpy). The solid-state structures of [Cu(POP)(6,6′-Cl2bpy)][PF6], [Cu(xantphos)(6,6′-Cl2bpy)][PF6]·CH2Cl2, [Cu(POP)(6-Brbpy)][PF6] and [Cu(xantphos)(6-Brbpy)][PF6]·0.7Et2O obtained from single crystal X-ray diffraction are described including the pressure dependence of the structure of [Cu(POP)(6-Brbpy)][PF6]. The copper(I) complexes with either POP or xantphos and 6,6′-Cl2bpy, 6-Brbpy and 6,6′-Br2bpy are orange-to-red emitters in solution and yellow-to-orange emitters in the solid state, and their electrochemical and photophysical properties have been evaluated with the help of density functional theory (DFT) calculations. The emission properties are strongly influenced by the substitution pattern that largely affects the geometry of the emitting triplet state. [Cu(POP)(6,6′-Cl2bpy)][PF6] and [Cu(xantphos)(6,6′-Cl2bpy)][PF6] show photoluminescence quantum yields of 15 and 17%, respectively, in the solid state, and these compounds were tested as luminophores in light-emitting electrochemical cells (LECs). The devices exhibit orange electroluminescence and very short turn-on times (<5 to 12 s). Maximum luminance values of 121 and 259 cd m−2 for [Cu(POP)(6,6′-Cl2bpy)][PF6] and [Cu(xantphos)(6,6′-Cl2bpy)][PF6], respectively, were achieved at an average current density of 100 A m−2. External quantum efficiencies of 1.2% were recorded for both complexes.

Graphical abstract: Luminescent copper(i) complexes with bisphosphane and halogen-substituted 2,2′-bipyridine ligands

Back to tab navigation

Supplementary files

Article information

06 Apr 2018
16 May 2018
First published
17 May 2018

Dalton Trans., 2018,47, 14263-14276
Article type

Luminescent copper(I) complexes with bisphosphane and halogen-substituted 2,2′-bipyridine ligands

S. Keller, A. Prescimone, H. Bolink, M. Sessolo, G. Longo, L. Martínez-Sarti, J. M. Junquera-Hernández, E. C. Constable, E. Ortí and C. E. Housecroft, Dalton Trans., 2018, 47, 14263
DOI: 10.1039/C8DT01338A

Social activity

Search articles by author