4373-60-8Relevant articles and documents
The dependence of oxygen sensitivity on the molecular structures of Ir(iii) complexes and their application for photostable and reversible luminescent oxygen sensing
Xing, Yang,Qiao, Chengfang,Li, Xinmin,Li, Chun,Wang, Honghao,Li, Fayun,Di, Ling,Yang, Zhanxu
, p. 15370 - 15380 (2019)
Three Ir(iii) complexes IrC1, IrC2, and IrC3 substituted with 4-(diphenylamino)phenyl (TPA), 4-(9H-carbazol-9-yl)phenyl (Cz1), and 9-phenyl-9H-carbazol-3-yl (Cz2) moieties were prepared and fully characterized as phosphorescent emitters. In comparison with Ir(ppy)3, introduction of TPA, Cz1, and Cz2 moieties strongly improved the oxygen sensitivities of IrC1-IrC3. Short-decayed IrC1 with I0/I100 of 168.6 and KappSV of 202.2 bar-1 in THF exhibited the highest sensitivity for oxygen. TPA and Cz moieties caused remarkable collision radius variations of the Ir(iii) complexes with 2.13 ± 0.08 for σIrC1/σIr(ppy)3, 1.24 ± 0.06 for σIrC2σIr(ppy)3, and 1.54 ± 0.08 for σIrC3σIr(ppy)3. For demonstrating the dependence of oxygen sensitivity on the molecular structure of the oxygen-sensitive probes (OSPs), the delocalization of spin populations (DSPs) has been applied for the first time to confirm the collision radius variations of Ir(iii) complexes. Remarkable DSPs were found on the TPA, Cz1, and Cz2 moieties with the spin population (percentage of the spin population) of 0.23210 (11.61%), 0.08862 (4.43%), and 0.13201 (6.60%), respectively. And strong linear correlations (R2 = 0.997) between the collision radius variations and spin population on TPA and Cz moieties were apparent. The DSPs could be used to describe the dependence of oxygen sensitivity on the molecular structure of the OSPs. For achieving real-time oxygen sensing, the photostability, oxygen sensing performance, and operational stability of IrC1-IrC3 and Ir(ppy)3 immobilized in ethyl cellulose (EC) were investigated. The IrC1-EC film demonstrated outstanding photostability after 60 min of irradiation and excellent operational stability for continuous oxygen monitoring with no attenuation of the original emission intensity in 4000 s. This study quantified and analyzed the dependence of oxygen sensitivity on the molecular structure of Ir(iii) complexes for the first time and illustrated a feasible approach to achieve high-efficiency sensors for real-time monitoring of oxygen.
Recyclable Ruthenium Catalyst for Distal meta-C?H Activation
Choi, Isaac,Müller, Valentin,Wang, Yanhui,Xue, Kai,Kuniyil, Rositha,Andreas, Loren B.,Karius, Volker,Alauzun, Johan G.,Ackermann, Lutz
, p. 15290 - 15297 (2020)
We disclose the unprecedented hybrid-ruthenium catalysis for distal meta-C?H activation. The hybrid-ruthenium catalyst was recyclable, as was proven by various heterogeneity tests, and fully characterized with various microscopic and spectroscopic techniques, highlighting the physical and chemical stability. Thereby, the hybrid-ruthenium catalysis proved broadly applicable for meta-C?H alkylations of among others purine-based nucleosides and natural product conjugates. Additionally, its versatility was further reflected by meta-C?H activations through visible-light irradiation, as well as para-selective C?H activations.
Chromium-Catalyzed Reductive Cleavage of Unactivated Aromatic and Benzylic C-O Bonds
Yuan, Shuqing,Ling, Liang,Tang, Jinghua,Luo, Meiming,Zeng, Xiaoming
, p. 3343 - 3350 (2021/07/02)
Reductive cleavage of aromatic and benzylic C-O bonds by chromium catalysis is reported. This deoxygenative reaction was promoted by low-cost CrCl 2precatalyst combined with poly(methyl hydrogen siloxane) as the mild reducing agent, providing a strategy in forming reduced motifs by cleavage of unactivated C-O bonds. A range of functional groups such as bromide, chloride, fluoride, hydroxyl, amino, and alkoxycarbonyl can be retained in the reduction.
Manipulating MLCT transition character with ppy-type four-coordinate organoboron skeleton for highly efficient long-wavelength Ir-based phosphors in organic light-emitting diodes
Deng, Xuming,Feng, Zhao,Sun, Yuanhui,Wu, Zhaoxin,Yang, Xiaolong,Yu, Yue,Zhong, Daokun,Zhou, Guijiang
supporting information, p. 12650 - 12660 (2021/10/06)
Inspired by the intriguing optoelectronic characteristics of the 2-phenylpyridine-type (ppy-type) four-coordinate organoboron skeleton, we envisage a molecular design strategy by manipulating the MLCT transition character to develop high-performance long-wavelength Ir-based phosphors with a ppy-type four-coordinate organoboron skeleton for organic light-emitting diodes (OLEDs). Three ppy-type cyclometalated Ir(iii) complexes are successfully prepared.IrOBNandIrPBNexhibit the expected long-wavelength phosphorescent emission at 620 and 604 nm, respectively, due to the electron-accepting ability of the pyridine coordinated with the boron atom (pyd(B)) in extending the π-conjugated length for the LUMO, thus leading to stabilization of the LUMO. Interestingly,IrMBNshows a green phosphorescence at 514 nm. The more electron-deficient pyd(B) inIrMBNleads to a reorganized and localized LUMO distribution pattern mainly on pyd(B) rather than the pyridine coordinated with the Ir atom (pyd(Ir)), shortening the π-conjugation length for the LUMO, hence resulting in an elevated LUMO. Benefiting from the high rigidity of the ppy-type four-coordinate organoboron skeleton, these three ppy-type cyclometalated Ir(iii) complexes show high PLQY (ca.0.6-1). Beneficially, we can achieve impressive electroluminescence (EL) performance based onIrPBNwith the highest efficiencies of a maximum external quantum efficiency (ηext) of 26.0%, a maximum current efficiency (ηL) of 42.0 cd A?1, and a maximum power efficiency (ηP) of 38.5 lm W?1, respectively. All these excellent results convincingly demonstrate the effectiveness of our molecular design strategy and the great potential of the ppy-type four-coordinate organoboron skeleton in developing high-performance Ir-based phosphors.
