Insertion of Unsaturated C–C Bonds into the O–H Bond of an Iridium(III)-Hydroxo Complex: Formation of Phosphorescent Emitters with an Asymmetrical β-Diketonate Ligand

Abstract

Structural Analysis of Complexes 4, 5, and 7 S3 Computational Details S5 Energies of Optimized Structures S5 UV-vis Spectra of Complexes 4-7 (Observed and Calculated) S9 Analysis of Computed UV/Vis Data for 4-7 S10 Cyclic Voltammograms of Complexes 4-7 S15 Theoretical Analysis of Molecular Orbitals of Complexes 4-7 S16 Normalized Excitation and Emission Spectra of Complexes 4-7 S25 NMR Spectra of Complexes 2-7 S29 References S42 S3 Experimental Section: General Information. All reactions were carried out with rigorous exclusion of air using Schlenk-tube techniques. Solvents were dried by the usual procedures and distilled under argon prior to use or obtained oxygen-and water-free from an MBraun solvent purification apparatus. C, H, and N analyses were carried out in a Perkin-Elmer 2400B SeriesII-Analyzer. High-resolution (HRMS) were acquired using a MicroTOF-Q hybrid quadrupole time-of-flight spectrometer (Bruker Daltonics, Bremen, Germany). MALDI-TOF mass spectra were acquired using a Bruker Autoflex III, MALDI-TOF/TOF equipped with a DCTB matrix. IR spectra were measured using a PerkinElmer Spectrum 100 FT-IR spectrometer, equipped with an ATR accessory, as pure solids. 1 H and 13 C{ 1 H} NMR spectra were recorded on a Bruker Avance 300 or 400 MHz instrument. Chemical shifts (expressed in parts per million) are referenced to residual solvent peaks. Coupling constants J are given in hertz. UV-visible spectra were registered on an Evolution 600 spectrophotomer. Steady-state photoluminescence spectra were recorded on a Jobin-Yvon Horiba Fluorolog FL-3-11 spectrofluorimeter. Lifetimes were measured using an IBH 5000F coaxial nanosecond flash lamp. Quantum yields were measured using the Hamamatsu Absolute PL Quantum Yield Measurement System C11347-11. Cyclic voltammetry measurements were performed using a Voltalab PST050 potentiostat with Pt wire as working electrode, Pt wire as counter electrode, and saturated calomel (SCE) as reference electrode. The experiments were carried out under argon in dichloromethane or acetonitrile solutions (10-3 M), with Bu 4 NPF 6 as supporting electrolyte (0.1 M). Scan rate was 100 mV s-1. The potentials were referenced to the ferrocene/ferrocenium (Fc/Fc +) couple. Preparation of [Ir(μ-Cl)(κ 2-C,N-C 6 H 4-isoqui) 2 (1). A suspension of [Ir(μ-Cl)(η 2-COE) 2 ] 2 (500 mg, 0.56 mmol) in 10 mL of 2-ethoxyethanol was treated with 1phenylisoquinoline (470 mg, 2.30 mmol) and the mixture was refluxed for 12 h. The resulting suspension was filtered and the red solid was washed with diethyl ether (3 x 10 mL). Yield: 620 mg (87%). 1 H NMR (300 MHz, CD 2 Cl 2 , 298 K): δ 9.00 (m, 4H), 8.20 (d,

Dissimilarity in the Chemical Behavior of Osmaoxazolium Salts and Osmaoxazoles: Two Different Aromatic Metalladiheterocycles

“… 28 However, in spite of the small number of transformations carried out with these compounds, some of them have proved to display catalytic ability to promote relevant organic transformations 29 and to perform reactions of interest in connection with materials science. 30 Hydroxide compounds of platinum-group metals have especially been scarcely studied; the number of known osmium species is particularly small. 31 Among the reported complexes, hydride-osmium-hydroxy derivatives are the most surprising and fascinating, 32 since the reductive elimination of water is a reaction generally favored from a thermodynamic point of view.…”

Red‐to‐NIR Iridium(III) Emitters: Synthesis, Photophysical and Computational Study, the Effects of Cyclometallating and β‐Diketonate Ligands

“…[1,9,17,23,24,26,27] The complexes containing β-diketonate ligands as L^L chelates are an important part of this family of emitters. [5,[28][29][30][31][32] These type of compounds differ from the other complexes containing neutral chelates (for example, aromatic diimines) by zero complex charge and stronger (covalent/electrostatic) binding to metal center. The simplest from the synthetic viewpoint and widely used β-diketonate ligands are symmetrical and do not contain the substituents with developed aromatic systems, [8,29,32,33] that prevents effective contribution of these ligands into MLCT or LC excited states due to high energy of their LUMO orbitals.…”

Phosphorescent Ir(iii) complexes derived from purine nucleobases

“…The weak absorption tails after 540 nm can be assigned to formally spin-forbidden 3 MLCT transitions caused by the large spin–orbit coupling introduced by the iridium center. 70,71,74…”