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Reverse vesicles exhibiting functions similar to thoseof normalvesicles have been constructed through the self-assembly of TTF/CBPQT4+-based pseudo[2]rotaxanes in a nonpolar solvent. The endsof the threads of the pseudo[2]rotaxanes are attached with a Fréchet-typeG-3 dendron and a hydrogen-bonded arylamide foldamer. These vesiclesexhibit a response to redox. By exploiting the dynamic featurespontaneouslyslow disassociation of the pseudorotaxanesthe sustained releaseof dyes embedded in the reverse vesicles has been demonstrated, whichcan be further tuned by changing the solvent polarity. [ABSTRACT FROM AUTHOR]

Abstract: Self-sorting is commonplace in biological system but seldom applied to orthogonally fabricating micro/nanoscaled objects. In this Letter, this principle has been employed to construct two different microscaled architectures via self-sorted assembly of size-matched disk-like molecules. A remarkable cooperative reinforcement of hydrogen-bonding and donor–acceptor interaction is also observed. [Copyright &y& Elsevier]

Abstract: Six-petal microflowers have been self-assembled in methanol from C 3-symmetric shape-persistent triangular aromatic hydrazide derivatives. Nine intramolecular hydrogen bonds are used to enhance the planarity of the aromatic backbone, while six 2-(2-(2-methoxyethoxy)ethoxy)-ethoxyl groups are appended to the rigid aromatic backbone. Scanning electron microscopy (SEM) images show that the molecules form unique six-petal flower-like aggregates in methanol. A self-assembling mechanism that is similar to the formation of snowflakes has been proposed. [Copyright &y& Elsevier]

Abstract: This Letter describes 2-(2-(dioctylamino)-2-oxoethyl-amino)-2-oxoethoxyl (DOAOE)-tuned self-assembly of vesicles from rigid macrocycles and foldamer-like oligomers. The molecules are prepared through the formation of reversible hydrazone bonds from aldehyde and benzo-hydrazide precursors, which are further facilitated by intramolecular N⋯H–O hydrogen bonding. SEM, AFM, and fluorescent encapsulation studies reveal that the molecules all self-assemble into vesicular structures in methanol, while similar molecules bearing the triethylene glycol or n-decyl chains do not. The results illustrate that DOAOE is robust in promoting the formation of vesicles for aromatic systems in polar solvents. [Copyright &y& Elsevier]

Abstract: In this paper, we report the synthesis and self-assembling behavior of an F⋯H–N hydrogen bonding-induced arylamide-based dipodal foldamer. SEM, AFM, TEM, and XRD studies reveal that this preorganized oligomer stacks to form vesicles in methanol–chloroform (10–70%) binary solvents due to the strong stacking interaction of the folded segments and the supramolecular polymeric feature of the dipodal molecule in the stacked state. In contrast, a simple folded molecule can give rise to vesicles only when the chloroform content is 45–55%. [Copyright &y& Elsevier]

Abstract: This paper describes an investigation of the structural and side-chain factors for the formation of vesicles and gels by hydrogen bonding-mediated aromatic hydrazide foldamers. Six foldamers and one straight analog that bear discrete side chains have been synthesized. SEM and AFM studies reveal that the molecules with the appended 2-(2-(dialkyl-amino)-2-oxoethylamino)-2-oxoethoxyl chains form vesicles, hydrogels or organogels, depending on the solvents. Both the inner amide units and the terminal N,N-dialkylamide units in the chains are revealed to play essential roles in controlling the self-assembly. The former facilitates it by forming the intermolecular hydrogen bonding, while the latter modulates it by providing solubility and balancing the hydrophobicity of the whole molecules in solvents of varying polarity. [Copyright &y& Elsevier]