1542275-72-8Relevant academic research and scientific papers
Nickel-Catalyzed Heteroarenes Cross Coupling via Tandem C-H/C-O Activation
Wang, Ting-Hsuan,Ambre, Ram,Wang, Qing,Lee, Wei-Chih,Wang, Pen-Cheng,Liu, Yuhua,Zhao, Lili,Ong, Tiow-Gan
, p. 11368 - 11376 (2018/11/23)
Inert aryl methyl ethers as coupling components via C-O activation have been established with a Ni catalyst for C-H activation of heteroarene. The key to simultaneous C-H/C-O bond activation is the use of sterically demanding o-tolylMgBr. The protocol is effective for a wide scope of substrates including naphthyl methyl ethers, anisoles, and a variety of other heteroarene derivatives. Detailed mechanistic studies indicated that the C-O cleavage is assisted via synergistic effect of nickel and Grignard reagent in this C-H/C-O reaction, which is supported by DFT calculation. At this stage, single-electron transfer can be ruled out as a main operative process for this tandem strategy.
Self-host homoleptic green iridium dendrimers based on diphenylamine dendrons for highly efficient single-layer PhOLEDs
Tian, Wenwen,Yi, Chang,Song, Bo,Qi, Qi,Jiang, Wei,Zheng, Yingping,Qi, Zhengjian,Sun, Yueming
, p. 1104 - 1115 (2014/02/14)
The fabrication of electroluminescent devices that combine high device performance with simple device configuration remains an attractive challenge due to their low cost and simple fabrication processes. In this paper, a new series of electrophosphorescent small molecule iridium(iii) complexes with diphenylamine-based dendrons of good solubility have been designed. The relationships between their dendritic structures and their photophysical, electrochemical, and electrophosphorescent performances have been systematically investigated. With second-generation dendrons, the photoluminescence quantum yields of the neat film of the dendrimers are almost seven times higher than that of their prototype G0 (Ir(LG0)3, LG0 = 1-methyl-2-phenyl-1H- benzimidazole), and three times that of the first-generation dendron G1 (Ir(LG1)3, LG1 = 4-(1-methyl-1H-benzimidazol-2-yl)-N,N- diphenylbenzenamine). High-quality films of the dendrimers G2 (Ir(LG2) 3, LG2 = 1-methyl-2-[4-bis[4-(diphenylamino)phenyl]-aminophenyl]-1H- benzimidazole) and G2Cz (Ir(LG2Cz)3, LG2Cz = 1-methyl-2-[4-bis[4-(9- carbazolyl)phenyl]-aminophenyl]-1H-benzimidazole) have been fabricated by spin-coating, producing highly efficient, non-doped phosphorescent organic light-emitting diodes (PhOLEDs). With a device structure of indium tin oxide/poly(3,4-ethylene-dioxythiophene):poly(styrene sulfonic acid)/neat dendrimer/Cs2CO3/Al, maximum luminous efficiencies of 14.02 cd A-1 and 18.35 cd A-1 have been realized, exhibiting ultrahigh luminous efficiency for single-layer self-host green PhOLEDs. The excellent performances are due to the flower bouquet-shaped iridium dendrimers, which may improve the electron injection and result in greater balance between electron and hole fluxes by the exposure of electron-deficient moieties. The molecular design reported here provides a simple and effective approach to balance charge injection/transporting capacities and develops highly efficient non-doped phosphors suitable for low-cost single-layer device technologies.
