Effect of ancillary ligands on the properties of diphenylphosphoryl-substituted cationic Ir(iii) complexes

Abstract

A new class of greenish-blue to blue emitting diphenylphosphoryl-substituted cationic cyclometalated Ir(iii) complexes (POF1–POF6) with different N^N ancillary ligands are reported.

Strategies on Cyclometalating Ligand Substitution of Several Ir(III) Complexes: Theoretical Investigation of Different Molecular Behaviors

“…It is noteworthy that cyclometalated Ir­(III) complexes are frequently considered to be the most promising phOLEDs due to their excellent phosphorescent quantum efficiency, thermal and electrochemical stability, and short lifetimes of the triplet excited state, as well as the tunability in red (700 nm or 1.77 eV) to blue (435.8 nm or 2.85 eV) color transformation, and have been extensively investigated in both experimental − and theoretical domains. − However, it is still a genuine challenge to develop blue-emitting phosphorescent complexes, since the IQE drops severely when the emission turns to blue. ,, The larger energy gap required by blue-emitting Ir­(III) complexes reduces the quantum yield mainly due to a significant increase in nonradiative decay rates. , A seminal sky blue phosphorescent cyclometalated Ir­(III) complex is the well-known iridium­(III) bis­[(4,6-difluorophenyl)-pyridinato- N , C 2′ ] picolinate (FIrpic), which has been demonstrated to be an excellent phosphorescent material in phOLEDs . The introduction of electron-withdrawing fluorine atoms on the ppy (2-phenylpyrdine) ligands, resulting in an enhancement of triplet exciton energy, renders a blue shift of phosphorescence .…”

“…14−18 However, it is still a genuine challenge to develop blue-emitting phosphorescent complexes, since the IQE drops severely when the emission turns to blue. 13,19,20 The larger energy gap required by blue-emitting Ir(III) complexes reduces the quantum yield mainly due to a significant increase in nonradiative decay rates. 21,22 A seminal sky blue phosphorescent cyclometalated Ir(III) complex is the well-known iridium(III) bis[(4,6-difluorophenyl)-pyridinato-N,C 2 ′] picolinate (FIrpic), 23 which has been demonstrated to be an excellent phosphorescent material in phOLEDs.…”

AIPE-active cationic Ir(iii) complexes for efficient detection of 2,4,6-trinitrophenol and oxygen

“…This may be attributed to the different nature of the emissive excited state, which contains much more 3 MLCT/ 3 LLCT character than Ir1 . 56 Compared with the emission of the monomer in CH 2 Cl 2 , both Ir1 and Ir2 have a larger red shift in the solid state. The maximum emission wavelength of Ir2 is bathochromic-shifted 58 nm compared to that of Ir1 , owing to the electron-donating ability of the DPA substituent.…”

A diphenylamino-substituted cationic cyclometalated Ir(iii) complex: its aggregation-induced phosphorescent emission and oxygen sensing properties

“…Both Ir(III) complexes [Ir(C^N) 2 (phen)]PF 6 were prepared using the same procedure according to literature methods. 38 IrCl 3 Á3H 2 O was reacted with 2.5 equiv. cyclometalating C^N ligand in a mixture of 2-ethoxyethanol and water (9 mL/3 mL) at 110 1C under nitrogen for 24 h to afford a cyclometalated iridium bridged-chloride dimer.…”

“…A series of platinum(II) and iridium(III) complexes as efficient OSPs have been synthesized and investigated. 5,[37][38][39][40][41][42] In this paper, a new diphenylamino (DPA)-substituted cationic bis-cyclometalated Ir(III) complex with AIPE properties was synthesized, which was used to explore the effects of the DPA group on the photophysical and electrochemical properties of the corresponding Ir(III) complex. In addition, the oxygen sensitivity and operational stability of the Ir(III) complex were studied.…”