552861-18-4Relevant articles and documents
Bicarbazoles: Systematic structure-property investigations on a series of conjugated carbazole dimers
Kato, Shin-Ichiro,Noguchi, Hiroto,Kobayashi, Atsushi,Yoshihara, Toshitada,Tobita, Seiji,Nakamura, Yosuke
, p. 9120 - 9133,14 (2012)
A large series of conjugated carbazole dimers, namely bicarbazoles 1-12, were synthesized by Suzuki-Miyaura, Sonogashira, Hay, and McMurry coupling reactions. In 1-12, the two carbazole moieties are linked at the 1-, 2-, or 3-position directly or via an acetylenic or olefinic spacer. The structure-property relationships, particularly the effects of the conjugation connectivity and the π-conjugated spacers on the electronic, photophysical, and electrochemical properties of 1-12, were studied by extensive UV-vis and fluorescence spectroscopic measurements, cyclic voltammetry (CV), and theoretical calculations as well as X-ray crystallographic analyses. The connection at the 1-position of carbazole ensures high extent of π-conjugation, while that at the 3-position enhances the electron-donating ability. Both acetylenic and olefinic spacers allow the extension of π-conjugation, and the latter also causes the increase of the donor ability. Moreover, the structural variations were found to affect the fluorescence quantum yields significantly, which are up to 0.84.
High-efficiency organic light-emitting diodes of phosphorescent PtAg2 heterotrinuclear acetylide complexes supported by triphosphine
Li, Yi-Peng,Fan, Xin-Xia,Wu, Yue,Zeng, Xian-Chong,Wang, Jin-Yun,Wei, Qiao-Hua,Chen, Zhong-Ning
, p. 3072 - 3078 (2017/03/30)
Three PtAg2 heterotrinuclear complexes supported by dpmp [dpmp = bis(diphenylphosphinomethyl)phenylphosphine] were prepared using carbazole-functionalized acetylides with hole-transport character as co-ligands. As established by X-ray crystallography, the PtAg2 array supported by dual dpmp exhibits a centre-symmetric linear arrangement with significant Pt-Ag interaction. They display intense phosphorescence in CH2Cl2 solutions (Φem = 56.9-65.3%) and doping films (Φem = 43.1-71.2%) at room temperature, originating primarily from 3[π(aromatic acetylides) → π*(dpmp)] 3LLCT and 3[π(aromatic acetylides) → s/p(PtAg2)] 3LMCT triplet states mixed with some PtAg2 cluster centred 3[d → s/p] character. Upon doping 8% PtAg2 complexes with blended host materials consisting of hole-transport TCTA and electron-transport OXD-7 as light-emitting layers, high-efficiency solution-processed organic light-emitting diodes were achieved with 67.4 cd A?1 peak current efficiency and 17.4% external quantum efficiency.
Carbazole-BODIPY conjugates: Design, synthesis, structure and properties
Misra, Rajneesh,Jadhav, Thaksen,Dhokale, Bhausaheb,Gautam, Prabhat,Sharma, Rekha,Maragani, Ramesh,Mobin, Shaikh M.
supporting information, p. 13076 - 13086 (2014/08/18)
A set of carbazole substituted BODIPYs 2a-2c were designed and synthesized by the Pd-catalysed Sonogashira cross-coupling reaction. The effects of variation in the donor strength of various carbazoles were investigated by photophysical, electrochemical and computational studies. The electronic absorption spectra of BODIPYs 2a and 2c show charge transfer bands, which show red shift in polar solvents. The BODIPYs 2a-2c are highly fluorescent in nonpolar solvents (emission from the localized state) and poorly fluorescent in polar solvents (emission from the charge transfer state). The photophysical and electrochemical studies reveal strong donor-acceptor interaction between carbazole and BODIPY and follows the order 2a > 2c > 2b. The computational calculations show good agreement with the experimental results. The single crystal structures of BODIPYs 2a-2c are reported, which exhibit interesting supramolecular interactions. The packing diagrams of 2a show a zigzag 3D structural arrangement, whereas 2b and 2c show complex 3D structural motifs. This journal is the Partner Organisations 2014.
