title: Synthesis and physical properties of the conjugated dendrons bearing twisted acenes used in solution processing of organic light-emitting diodes.
abstract: Five novel organic conjugated derivatives containing multifraction twisted acene units have been synthesized and characterized. These compounds and the model molecule 2-methyl-5,12-diphenyl-6:7,10:11-bisbenzotetracene emit strong blue light in diluted solution with quantum yields of 0.21-0.67, while in the solid state, except for the 1,2,3,4,5,6-hexa(2-(5,12-diphenyl-6:7,10:11-bis(4'-tert-butylbenzo)tetracene))benzene, green luminance is seen. The experimental results also indicate that the multifraction structure leads to a significant fluorescence enhancement (over two times) compared to the monomer, which might be attributed to the formation of delocalized excited state in multibranch structures. The quantum-chemical calculation implies that only two branches are involved in formation of the delocalized system for the multibranched derivatives. Furthermore, the organic light-emitting diode (OLED) devices using compounds 1,4-di(2-(5,12-diphenyl-6:7,10:11-bis(4'-tert-butylbenzo)tetracene))benzene, 1,3-di(2-(5,12-diphenyl-6:7,10:11-bis(4'-tert-butylbenzo)tetracene))benzene, and 1,3,5-tri(2-(5,12-diphenyl-6:7,10:11-bis(4'-tert-butylbenzo)tetracene))benzene as emitters exhibit good electroluminescent performance. Our systematic studies might provide more chances to challenge the rational design and synthesis of new- and high-generation branched dendrimers.
authors.affiliation: College of Chemistry and Environment Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University , Baoding 071002, P. R. China.
authors.forename: Zhenying
authors.initials: Z
authors.lastname: Liu
authors.forename: Jinchong
authors.initials: J
authors.lastname: Xiao
authors.forename: Qiang
authors.initials: Q
authors.lastname: Fu
authors.forename: Huanran
authors.initials: H
authors.lastname: Feng
authors.forename: Xuemin
authors.initials: X
authors.lastname: Zhang
authors.forename: Tiejun
authors.initials: T
authors.lastname: Ren
authors.forename: Sujuan
authors.initials: S
authors.lastname: Wang
authors.forename: Dongge
authors.initials: D
authors.lastname: Ma
authors.forename: Xuefei
authors.initials: X
authors.lastname: Wang
authors.forename: Hua
authors.initials: H
authors.lastname: Chen