80635-91-2Relevant articles and documents
Visible Light Induced Rhodium(I)-Catalyzed C?H Borylation
Thongpaen, Jompol,Manguin, Romane,Dorcet, Vincent,Vives, Thomas,Duhayon, Carine,Mauduit, Marc,Baslé, Olivier
supporting information, p. 15244 - 15248 (2019/10/22)
An efficient visible light induced rhodium(I)-catalyzed regioselective borylation of aromatic C?H bonds is reported. The photocatalytic system is based on a single NHC?RhI complex capable of both harvesting visible light and enabling the bond breaking/forming at room temperature. The chelating nature of the NHC-carboxylate ligand was critical to ensure the stability of the RhI complex and to provide excellent photocatalytic activities. Experimental mechanistic studies evidenced a photooxidative ortho C?H bond addition upon irradiation with blue LEDs, leading to a cyclometalated RhIII-hydride intermediate.
Effect of substitution of methyl groups on the luminescence performance of IrIII complexes: Preparation, structures, electrochemistry, photophysical properties and their applications in organic light-emitting diodes (OLEDs)
Jung, Sungouk,Kang, Youngjin,Kim, Hyung-Sun,Kim, Yun-Hi,Lee, Chang-Lyoul,Kim, Jang-Joo,Lee, Sung-Koo,Kwon, Soon-Ki
, p. 3415 - 3423 (2007/10/03)
A series of dimethyl-substituted tris(pyridylphenyl)iridium(III) derivatives [(n-MePy-n′-MePh)3Ir] [n = 3, n′ = 4 (1); n = 4, n′ = 4 (2); n = 4, n′ = 5 (3); n = 5, n′ = 4 (4); n = 5, n′ = 5 (5)] have been synthesized and characterized to investigate the effect of the substitution of methyl groups on the solid-state structure and photo- and electroluminescence. The absorption, emission, cyclic voltammetry and electroluminescent performance of 1-5 have also been systematically evaluated. The structures of 2 and 4 have been determined by a single-crystal X-ray diffraction analysis. Under reflux (> 200 °C) in glycerol solution, fac-type complexes with a distorted octahedral geometry are predominantly formed as the major components in all cases. Electrochemical studies showed much smaller oxidation potentials relative to Ir(ppy)3 (Hppy = 2-phenylpyridine). All complexes exhibit intense green photoluminescence (PL), which has been attributed to metal-to-ligand charge transfer (MLCT) triplet emission. The maximum emission wavelengths of thin films of 1, 3, 4 and 5 at room temperature are in the range 529-536 nm, while 2 displays a blue-shifted emission band (λmax = 512 nm) with a higher PL quantum efficiency (ΦPL = 0.52) than those of complexes 1 and 3-5; this is attributed to a decrease of the intermolecular interactions. Multilayered organic light-emitting diodes (OLEDs) were fabricated by using three (2, 3 and 4) of these IrIII derivatives as dopant materials. The electroluminescence (EL) spectra of the devices, which have the maximum peaks at 509-522 nm, with shoulder peaks near 552 nm, are consistent with the PL spectra in solution at 298 K. The devices show operating voltages at 1 mA/cm 2 of 4,9, 5.6, 5,1, and 4.6 V for Ir(ppy)3, 2, 3, and 4, respectively. In particular, the device with 2 shows a higher external quantum efficiency (ηext = 11% at 1 mA/cm2) and brightness (4543 cd/m2 at 20 mA/cm2) than Ir(ppy)3 (ηext = 6.0% at 1 mA/cm2; 3156 cd/m2 at 20 mA/cm2) and other Ir(dmppy)3 derivatives, (dmppy = dimethyl-substituted ppy), under the same conditions. The methyl groups at the meta (Ph) and para (Py) positions to the Ir metal atom have a great influence on absorption, emission, redox potentials and electroluminescence. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
