Journal of Nanomedicine & Nanotechnology

Homoleptic triscyclometalated iridium(III) complexes based on highly luminescent 2,4-diarylsubstituted quinolines containing 4-fluorophenylvinyl moieties: Potential materials for organic light emitting diodes (OLEDs)

4^th International Conference on Nanotek & Expo

December 01-03, 2014 DoubleTree by Hilton Hotel San Francisco Airport, USA

Adewale O Adeloye, Malose J Mphahlele and Abolanle S Adekunle

Accepted Abstracts: J Nanomed Nanotechnol

Abstract:

In the present work, four new series of highly luminescent cationic homoleptic iridium (III) cyclometalated complexes of the type [Ir(NΛC)3]PF6 based on derivatives of 4-fluoro- phenylvinylquinolines containing electron donating and withdrawing groups as aryl-substituents at 2-position of the quinoline scaffold were synthesized and characterized. While the ligands were initially prepared via palladium catalyzed Suzuki-Miyaura cross-coupling of the 2-aryl-4-chloroquinoline, cyclometalation of Ir(III) complex is accomplished in one-pot reaction method. The spectroscopic and photophysical properties of the compounds were determined using FT-IR, NMR, UV-Vis absorption, PL spectroscopy. Strong singlet metal-to-ligand charge transfer (1MLCT) absorption peaks were found between 338-410 nm in methanol. The photoluminescence properties of the ligands measured in solvents of different polarity were tuned by modification with wavelengths displaying a red-shift emission from 440-490 nm when compared to 480?550 nm in the complexes, and maximum enhanced fluorescence intensities and high quantum yield observed in chloroform and methanol unlike in dimethylformamide (DMF), suggesting the intramolecular charge transfer (ICT) character of the emission state. Electrochemical properties show the complexes to be redox-active in nature. The high emission intensity of the complexes endear them to be applied as new materials in the area of OLEDs, temperature and oxygen sensors.