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Spirofluorene‐cored bis(difluoroboron β‐diketonate) complexes bearing terminal carbazoles (CbzBSF) and tert‐butylcarbazoles (TCbzBSF) have been synthesized. It was found that only TCbzBSF could form organogels in cyclohexane and methylcyclohexane, suggesting that tert‐butylcarbazole was essential for its organogelation directed by weak π–π interactions. It is worth noting that TCbzBSF could entrap ca. 5800 molecules of methylcyclohexane per gelator molecule, so this fully conjugated complex without traditional gelation group could be considered as a supergelator. The gained organogel showed reversible thixotropic and temperature‐dependent sol‐gel transitions. In particular, the orange red fluorescence of the xerogel‐based film of TCbzBSF could be quenched when exposed to gaseous aromatic amines of aniline, N‐methylaniline, and N,N‐dimethylaniline. The detection limit for aniline vapor of the xerogel‐based film was as low as 0.56 ppb. [ABSTRACT FROM AUTHOR]

Novel luminescent organogelators based on nucleoside functionalized with carbazole (UC8, UC12 and UC16) were designed and synthesized. Their gelation ability was tested and it was found that both UC12 and UC16 could form stable organogels in toluene/petroleum ether. The UV-vis absorption, fluorescence emission and IR spectral changes during the gelation of UC12 proved that the self-assembly was driven by H- bonding. The morphology of the xerogel UC16 obtained from toluene/petroleum ether (v/v = 1/1) displayed tough rod-like microstructures, and 3D networks formed from lots of nanofibers were observed for the xerogel UC16 obtained from toluene/petroleum ether (v/v = 2/1). It was interesting that the obtained organogels emitting blue light could be destroyed by the addition of F-, accompanied with the declining the emission intensity. Therefore, these organogels could be used as sensory materials to recognize F-. [ABSTRACT FROM AUTHOR]

Four cyanostyryl-substituted carbazole derivatives (CN-ODEC1, CN-ODEC2, CN-DDEC1, and CN-DDEC) were synthesized and their self-assembly properties have been studied. It was found that they could form organogels especially in aromatic solvents. Scanning electron microscopy and light microscopy images show that the xerogels formed from monosubstituted derivatives (CN-O/DDEC1) gave well-organized tapes, and those from disubstituted derivatives (CN-O/DDEC2) exhibited heavy entangled three-dimensional structures. The UV–vis absorption and fluorescence emission spectra, as well as X-ray diffraction patterns, suggest that carbazole derivatives underwent J-type π-stacking. Meanwhile, we suggested that strong H-bonding and moderate π–π interactions were the key driving force for the gelation of the monosubstituted derivatives, and head-to-tail “ladder-type” J-aggregates were formed in the gel state. On the other hand, strong π–π interaction might be considered as the main driving force for the gelation of disubstituted derivatives, and J-aggregates with no well-organized packing mode of molecules were obtained in the gel phase. It should be noticed that aggregation-induced emission was observed during the gelation processes. [ABSTRACT FROM AUTHOR]

New triphenylvinyl substituted carbazole derivatives TPEICE , TPEC and TPECBr have been synthesized. They could self-assemble into nanofibers via organogelation processes in some organic solvents. Notably, the obtained xerogel-based films could emit strong fluorescence although the three compounds were non-emissive in solutions, indicating AIE in gel phases. The emission of TPEICE and TPEC in xerogel-based films could be quenched significantly upon exposed to gaseous DNT and TNT, while TPECBr could not sense nitro compounds on account of its poor electron donating ability. We also found that reversibility of the fluorescence response of TPEC was better than TPEICE because the photo-induced electron transfer would happen during the recognition of nitroaromatics for TPEICE and TPEC , except for the formation of charge–transfer complex between TPEICE and nitro compounds. Therefore, the different fluorescence response behaviors of TPEICE , TPEC and TPECBr towards nitroaromatics were resulted from their different electron donating abilities. [ABSTRACT FROM AUTHOR]