Synthesis and characterization of blue-violet emitting iridium(III) complex coordinated via chlorinated ancillary ligand

Abstract

Refluxing HL [5-chloro-2-((2-hydroxynaphthalen-1-yl)diazenyl)phenyl)(phenyl)methanone] with [(2-ppy)₂Ir(μ-Cl)]₂ in ethanol-dichloromethane mixture in the presence of a base (NEt₃) afforded complex of composition [Ir(2-ppy)₂(L)], where the azo-ligand is coordinated to iridium(III) center as monoanionic bidentate N,O-donors. The ligand and complex were characterized unequivocally. Molecular structures of both the ligand and complex were confirmed by single-crystal X-ray diffraction. The ground and excited-state geometries, absorption, and emission properties of the iridium(III) complex were further examined by DFT and TD-DFT methods. The complex exhibits a blue-violet emission band at 395 nm with quantum yield (Φ) 0.06. Experimental and theoretical studies support the fact that the nature of emission is an admixture of ³IL and ³MLCT state.

Graphical Abstract

Keywords:

• Azo ligand
• heteroleptic iridium(III) complex
• X-ray structure
• photoluminescence
• theoretical investigation

Acknowledgements

S. Debnath thanks DST-inspire and S.P.P. thanks the DST-SERB (New Delhi) for research fellowship. The necessary laboratory and Infrastructural facility is provided by the Department of Chemistry, Jadavpur University.

Disclosure statement

No potential conflict of interest was reported by the authors.