1360743-16-3Relevant articles and documents
Three-carbazole-armed host materials with various cores for RGB phosphorescent organic light-emitting diodes
Su, Shi-Jian,Cai, Chao,Kido, Junji
, p. 3447 - 3456 (2012)
A series of three-carbazole-armed host materials containing various arylene cores, like benzene (1,3,5-tris(3-(carbazol-9-yl)phenyl)-benzene, TCPB), pyridine (2,4,6-tris(3-(carbazol-9-yl)phenyl)-pyridine, TCPY), and pyrimidine (2,4,6-tris(3-(carbazol-9-yl)phenyl)-pyrimidine, TCPM), were developed for red, green, and blue phosphorescent organic light-emitting diodes (OLEDs). An intramolecular charge transfer was observed for TCPY and TCPM with heterocyclic cores of pyridine and pyrimidine, giving bathochromic shifts in the photoluminescent spectrum and reduced energy band gaps in comparison with TCPB with a benzene core. In addition, lower energy singlet and triplet excited states, reduced lowest unoccupied molecular orbital (LUMO) energy level, smaller singlet-triplet exchange energy (ΔEST), and improved bipolarity were also achieved with introducing heterocycles of pyridine and pyrimidine instead of benzene. In contrast to the slightly decreased triplet energy (ET), a significantly decreased ΔEST was achieved by introducing heterocycles of pyridine and pyrimidine as the core, and the more nitrogen atoms in the central heterocycle, the smaller ΔE ST is achieved. Reduced driving voltages were achieved for the green and red phosphorescent OLEDs by utilizing TCPY and TCPM as the host due to their decreased ΔEST and lower-lying LUMO energy level, proving that more carriers must be injected into the emitting layer through the host molecules rather than direct carrier trapping by the dopant. Moreover, improved efficiency and suppressed efficiency roll-off were also achieved for the green and red phosphorescent OLEDs based on TCPY and TCPM due to their improved bipolarity and thus improved carrier balance.
An efficient, green solvent-free protocol for the synthesis of 2,4,6-triarylpyridines using reusable heterogeneous activated Fuller’s earth catalyst
Rekunge, Deelip S.,Kale, Ishwari A.,Chaturbhuj, Ganesh U.
, p. 2455 - 2462 (2018/09/13)
Abstract: A simple, efficient, and green method of preparation for the synthesis of highly substituted pyridines by multicomponent reaction of acetophenones, aldehydes, and ammonium acetate using activated Fuller’s earth as an effective and reusable heterogeneous catalyst is described. The advantages of the present protocol include simple procedure with an easy workup procedure, mild reaction conditions, and high yields of the products. The performance of this reaction under solvent-free conditions using heterogeneous catalysts, such as activated Fuller’s earth, could enhance its efficiency from an economic as well as ecological point of view. Graphical abstract: [Figure not available: see fulltext.].
PHOSPHINE OXIDE COMPOUND, ORGANIC ELECTROLUMINESCENCE ELEMENT, PRODUCTION METHOD AND USES THEREOF
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, (2012/10/18)
A compound having a stable deposition rate suitable for forming an electron-transporting layer of an organic El element. The compound is represented by the following formula (1): wherein in the formula (1), plural R1 are each an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogen atom, or a hydrogen atom, and may be the same as or different from one another; and plural Ar are each a monovalent substituted or unsubstituted aromatic group optionally containing a hetero atom, and may be the same as or different from one another.
