title: Poly(aryl ether) Dendrons with Monopyrrolotetrathiafulvalene Unit-Based Organogels exhibiting Gel-Induced Enhanced Emission (GIEE).
abstract: A series of poly(aryl ether) dendrons with a monopyrrolo-tetrathiafulvalene unit linked through an acyl hydrazone linkage were designed and synthesized as low molecular mass organogelators (LMOGs). Two of the dendrons could gelate the aromatic solvents and some solvent mixtures, but the others could not gel all solvents tested except for n-pentanol. A subtle change on the molecular structure produces a great influence on the gelation behavior. Note that the dendrons could form the stable gel in the DMSO/water mixture without thermal treatment and could also form the binary gel with fullerene (C60 ) in toluene. The formed gels undergo a reversible gel-sol phase transition upon exposure to external stimuli, such as temperature and chemical oxidation/reduction. A number of experiments (SEM, FTIR spectroscopy, (1) H NMR spectroscopy, and UV/Vis absorption spectroscopy, and XRD) revealed that these dendritic molecules self-assembled into elastically interpenetrating one-dimensional fibrillar aggregates and maintain rectangular molecular-packing mode in organogels. The hydrogen bonding, π-π, and donor-acceptor interactions were found to be the main driving forces for formation of the gels. Moreover, the gel system exhibited gel-induced enhanced emission (GIEE) property in the visible region in spite of the absence of a conventional fluorophore unit and the fluorescence was effectively quenched by introduction of C60 .
authors.affiliation: Key Laboratory of Natural Resources of Changbai Mountain & Functional Molecules of Ministry of Education, Yanbian University, Yanji, Jilin 133002 (P.R. China), Fax: (+86) 433-2732456.
authors.forename: Yucun
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Key Laboratory of Natural Resources of Changbai Mountain & Functional Molecules of Ministry of Education, Yanbian University, Yanji, Jilin 133002 (P.R. China), Fax: (+86) 433-2732456.
authors.forename: Wenwei
authors.initials: W
authors.lastname: Lei
authors.affiliation: Key Laboratory of Natural Resources of Changbai Mountain & Functional Molecules of Ministry of Education, Yanbian University, Yanji, Jilin 133002 (P.R. China), Fax: (+86) 433-2732456.
authors.forename: Tie
authors.initials: T
authors.lastname: Chen
authors.affiliation: Key Laboratory of Natural Resources of Changbai Mountain & Functional Molecules of Ministry of Education, Yanbian University, Yanji, Jilin 133002 (P.R. China), Fax: (+86) 433-2732456.
authors.forename: Longyi
authors.initials: L
authors.lastname: Jin
authors.affiliation: Key Laboratory of Natural Resources of Changbai Mountain & Functional Molecules of Ministry of Education, Yanbian University, Yanji, Jilin 133002 (P.R. China), Fax: (+86) 433-2732456.
authors.forename: Guangyan
authors.initials: G
authors.lastname: Sun
authors.affiliation: Key Laboratory of Natural Resources of Changbai Mountain & Functional Molecules of Ministry of Education, Yanbian University, Yanji, Jilin 133002 (P.R. China), Fax: (+86) 433-2732456. zqcong@ybu.edu.cn.
authors.forename: Bingzhu
authors.initials: B
authors.lastname: Yin
keywords: dendrons; fluorescence; gels; redox chemistry; self-assembly