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Abstract: Four new well-defined monodisperse linear oligofluorenes with anthracene core An-OFVn (n =1–4) have been synthesized through Heck and Wittig reaction. These conjugated oligomers exhibit good solubility in common organic solvents. It is found that the conjugation length of the oligomers can be extended and the formation of excimers can be suppressed with increasing the number of fluorene–vinylene units linked in the 9,10-positions of anthracene. [Copyright &y& Elsevier]

Abstract: Novel monodisperse linear 3,9-linked oligocarbazoles (OCAs) were prepared stepwise using Ullmann coupling reaction in seal-tubes. The resulting OCAs were soluble in common organic solvents. The UV–vis spectra of OCAs exhibited small red shift and their intensities increased linearly with the increase of the carbazole moieties, suggesting that no intramolecular π-interactions appeared at ⩽8-mer. All the OCAs gave strong fluorescence and it was found that the conjugated degree of linear OCAs would be saturated when the number of carbazole units reaches four. [Copyright &y& Elsevier]

We have synthesized two new two-photon active dendritic molecules with tetraphenylmethane core with four phenothiazine-based arms. They show good solubility in organic solvents, including dichloromethane, chloroform, toluene and tetrahydrofuran. It is found that the two dendrimers display strong two-photon absorption and two-photon excited up-conversion fluorescence at 800 nm. • Two new phenothiazine-based dendrimers with tetraphenylmethane cores have been synthesized. • The dendritic molecules display two-photon absorption activity. • The two-photon absorption cross section increased with the increasing of the conjugation degree. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents novel organogelators based on long chain substituted benzoic acid hydrazine which can form stable gels in bulk organic solvents and self-assemble into various microstructures in organogel phases. It is found that hydrogen bonding and van der Waals interaction play an important role on the formation of organogel. [Copyright &y& Elsevier]

Abstract New carbazole-modified pyrazole derivatives were synthesized. It was found that tert -butylcarbazole derivatives of TCPDP , TCPHP , TCPPM and TCPPF exhibited reversible mechanofluorochromic (MFC) behavior under the treatment of grinding/fuming with CH 2 Cl 2. Particularly, the emission of the as-synthesized crystals of TCPDP was weak and emerged in the ultraviolet region, while the grinding led to significant red-shift of the emission to the visible-light region, accompanied with the significant fluorescence enhancement on account of the formation of J -aggregates. Thus, TCPDP showed intriguing fluorescence switching in visible-light region during MFC processes, which could be easily observed visually. Additionally, TCPDP , TCPHP , TCPPM and TCPPF could form stable organogels in some organic solvents. Notably, the solutions of TCPPM and TCPPF were almost non-emissive, but gelation-induced blue emission was achieved. Thus, the fluorescence could be also turned on due to the AIE (aggregation-induced emission) during the gel formation. Graphical abstract Image 1 Highlights • New carbazole-modified pyrazole derivatives were synthesized. • Tert -butylcarbazole derivatives showed reversible mechanofluorochromism and good gelation abilities. • High-contrast mechanofluorochromism of TCPDP was achieved via fluorescence switching in visible-light region. • Gelation-induced emission of TCPPM and TCPPF was detected. [ABSTRACT FROM AUTHOR]

Abstract: New well-defined monodisperse oligocarbazoles-functionalized anthracenes An-OCZn (n =1, 2, 3) have been synthesized through Suzuki cross-coupling reaction of the brominated oligocarbazoles and 9,10-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)anthracene. They show good solubility in organic solvents, including dichloromethane, chloroform, toluene, ethyl acetate, and tetrahydrofuran. It should be noted that, in the case of An-OCZn, the formation of the excimer based on anthracene unit is suppressed completely due to the introduction of oligocarbazoles in 9,10-position of anthracene so that an intense blue-emitting has been afforded. In addition, the obtained An-OCZn exhibit good electrochemical and thermal stabilities. Thus, the oligocarbazoles-functionalized anthracenes can be a class of promising candidates for novel blue-emitting materials employed in OLEDs or related devices. [Copyright &y& Elsevier]