Design of (NHC) Copper(I) complexes bearing dipyridylamine ligands for application in luminescent materials

Margaux Elie (1) , Fabien Sguerra (2) , Florent Di Meo (3) , Michael D. Weber (4) , Ronan Marion , Jean-Luc Renaud (1) , Mathieu Linares (5) , Matthieu Hamel (2) , Sylvain Gaillard (1) , Rubén D. Costa (6)

1 LCMT - Laboratoire de chimie moléculaire et thioorganique
2 LCAE - Laboratoire Capteurs et Architectures Electroniques
3 LIU - Linköping University
4 Department of Chemistry and Pharmacy, Emil Fischer Center, University of Erlangen-Nuremberg - Schuhstr. 19, 91052 Erlangen DE
5 IFM - Department of Physics, Chemistry and Biology [Linköping]
6 FAU - Friedrich-Alexander Universität Erlangen-Nürnberg

We present in this communication the synthesis of new cationic tricoordinated copper complexes bearing bidentate dipyridylamine (dpa) ligands and NHC as ancillary ligands [Cu(NHC)(HDPA)][X].(1,2) These copper complexes have been fully characterized by NMR, X-ray analysis, electrochemistry, and photophysics. TD-DFT calculations were also undergoneto rationalize the assignment of the photophysical properties. Some of these copper complexes exhibit very bright blue emission with high quantum yield at solid state. A variation of the electronic properties on both NHC and dipyridylamine ligands, has been carried out and permitted to establish a structure – properties relationship, also supported by TD-DFT calculations. A photophysical study at low temperature highlighted a specific luminescence phenomenon of the complexes: Thermally Activated Delayed Flurorescence. Since emissive cationic organometallic complexes can be good candidates for LEC (Light emittingElectrochemical Cells) applications, a selection of copper complexes was achieved for the preparation of those lighting devices. Here is presented the proof of concept that our copper complexes, of general formula [Cu(NHC)(dpa)][X], can be applied for LEC devices. To the best of our knowledge, we are presenting here the first blue emitting LEC device incorporating cationic copper complexes.

Keywords: TD-DFT calculations; electronic properties; Light emitting Electrochemical Cells; Thermally Activated Delayed Flurorescence; cationic tricoordinated copper complexes; photophysics; photophysical properties; X-ray analysis; NHC; electrochemistry; NMR; bidentate dipyridylamine ligands; blue emission; luminescence

Domains: Chemical Sciences; Physics [physics]; Condensed Matter [cond-mat]; Materials Science [cond-mat.mtrl-sci]; Engineering Sciences [physics]; Micro and nanotechnologies/Microelectronics

Margaux Elie, Fabien Sguerra, Florent Di Meo, Michael D. Weber, Ronan Marion, et al.. Design of (NHC) Copper(I) complexes bearing dipyridylamine ligands for application in luminescent materials: (NHC) Cu(I) Complexes bearing Dipyridylamine ligands - Synthesis, Structural, Photoluminescent Studies and Applications in Luminescent Materials. 13th Anglo-Norman Organic Chemistry Colloquium (ANORCQ XIII), Apr 2016, Rouen, France. . ⟨hal-02434048⟩