288105-04-4Relevant articles and documents
Synthesis of Fluorene-Bridged Arylene Vinylene Fluorophores: Effects of End-Capping Groups on the Optical Properties, Aggregation Induced Emission
Zhang, Guo-Feng,Chen, Tao,Chen, Ze-Qiang,Aldred, Matthew P.,Meng, Xianggao,Zhu, Ming-Qiang
, p. 939 - 947 (2015/09/01)
We have synthesized a series of fluorene-based fluorophores, in which a central fluorene core has been modified with different peripheral arylene vinylene substituents that are able to activate aggregation-induced emission (AIE) characteristics. 9,9-Dioctylfluorene doubly end-capped at the 2,7-positions with triphenylethene groups, such as 4-(2,2-diphenylvinyl)phenyl (F1-(2,2)-HTPE) and 4-(1,2-diphenylvinyl)phenyl (F1-(1,2)-HTPE) were synthesized and compared to the tetraphenylethene analogue (F1-TPE). Both F1-(2,2)-HTPE and F1-(1,2)-HTPE glow with a deep blue fluorescence in THF solution with emission maxima (λem) of 426 and 403 nm, respectively. The λem slightly red-shifts in the solid-state to 458 nm for F1-(2,2)-HTPE and 437 nm for F1-(1,2)-HTPE. The fluorescence quantum yields (Φ;F) of F1-(2,2)-HTPE (?F=35.1 %) and F1-(1,2)-HTPE (?F=26.2%) were found to be higher in solution compared to the near quenching of F1-TPE (?F=0.1%). Consequently, this results in weaker AIE-stability of F1-(2,2)-HTPE (αAIE=1.5) and F1-(1,2)-HTPE (αAIE=1.9) compared to F1-TPE (αAIE=125), suggesting that four phenyl groups are necessary for efficient AIE-activity of these fluorene bridged arylene vinylene type materials. In addition, decreasing the steric hindrance around the arylene vinylene moiety by removal of a phenyl ring is another method to decrease the AIE characteristics, in a similar manner to the commonly known ?phenyl-locking?. Non-polar triphenylethenes are poorer AIE materials than their tetraphenylethene analogues. Replacing the hydrogen atom of F1-(2,2)-HTPE with a cyano group affords fluorene end-capped with 2,3,3-triphenylacrylonitrile (F1-TPAN), which boosts the AIE-effect to αAIE=90.5 and red-shifts the solid-state emission (λem=528 nm) with near quenching in THF solution (?F=0.12%). X-ray crystallographic analysis of F1-TPAN indicates that the introduction of cyano groups can not only diminish the intramolecular steric hindrance in comparison of F1-TPE, but also improve the molecular cohesion ability via multiple C-H···N interactions. Four different arylene vinylene substituents attached to the fluorene were synthesized, and the disparities of AIE-effect of these compounds were discussed. The cyano-groups in F1-TPAN will not only reduce the steric congestion of the peripheral phenyl rings, but also appreciably improve the molecular cohesion ability via multiple C-H?N interactions.
Suppression of aggregation-induced fluorescence quenching in pyrene derivatives: Photophysical properties and crystal structures
Liang, Zuo-Qin,Li, Ye-Xin,Yang, Jia-Xiang,Ren, Yan,Tao, Xu-Tang
, p. 1329 - 1333 (2011/04/15)
Two new pyrene-based fluorophores, namely 1-[4-(2,2-diphenylvinyl)phenyl] pyrene (PVPP) and 1,3,6,8-tetrakis[4-(2,2-diphenylvinyl)phenyl]pyrene (TPVPP), were synthesized through Suzuki coupling reaction and well characterized. PVPP successfully suppresses the fluorescence quenching of pyrene units in the solid state, displaying aggregation-induced enhanced emission. Despite the same substituent, TPVPP shows a different fluorescent behavior. On the basis of the crystal structures, the distinct optical behavior is discussed and clarified. The intermolecular C-H?π interaction has a dramatic effect on their photophysical properties in the solid state.
NOVEL THIOPHENE-BASED DYE AND PREPARATION THEREOF
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Page/Page column 70-72, (2009/05/28)
The present invention relates to a thiophene-based dye and a preparation thereof, and more particularly, to dye compounds, which are used for a dye-sensitized solar cell (DSSC), and provides better molar extinction coefficient, JSc (short-circuit photocurrent density) and photoelectric conversion efficiency than a conventional dye to enhance efficiency of a solar cell.
