102362-01-6Relevant articles and documents
A facile color-tuning strategy for constructing a library of Ir(III) complexes with fine-tuned phosphorescence from bluish green to red using a synergetic substituent effect of -OCH3 and -CN at only the C-ring of C∧N ligand
Jiao, Yan,Li, Ming,Wang, Ning,Lu, Tao,Zhou, Liang,Huang, Yan,Lu, Zhiyun,Luo, Daibing,Pu, Xuemei
, p. 4269 - 4277 (2016/06/01)
By simply grafting a -CN group and/or a -OCH3 group onto the meta- and/or para-site of the C-ring, a series of Ir(iii) complexes bearing a similar molecular platform of bis(1,2-diphenyl-1H-benzimidazolato-N,C2′)iridium(iii)(acetylacetonate), but showing fine-tuned phosphorescence covering nearly the whole window of the visible spectrum with a wide color-tuning range of 109 nm was acquired. With the help of DFT calculations, it was revealed that if the C-related arene moiety of the C∧N ligand (C-ring) contributes substantially to both the HOMO and LUMO of an Ir(iii) complex, the concurrent introduction of an electron-donating -OCH3 and an electron-withdrawing -CN groups on the C-ring at the meta- and para-sites relative to the Ir atom may lead to a favorable synergetic substituent effect on the color-tuning direction. This may represent a facile yet effective molecular design strategy for Ir(iii) complexes with a desirous emission color. A bluish green organic light-emitting diode (OLED) based on one of the objective complexes displayed a maximum current efficiency of 62.1 cd A-1, an external quantum efficiency of 19.8%, and a brightness of 48-040 cd m-2, implying that high-performance red and blue OLED phosphors as well as libraries of Ir(iii) complexes bearing similar molecular platforms may be developed through this -OCH3 and -CN synergetic substitution strategy.
