Vesicles and Organogels from Foldamers: A Solvent-Modulated Self-Assembling Process
摘要:
Nonamphiphilic, hydrogen-bonded hydrazide foldamers appended with four or six long flexible chains were revealed to spontaneously assemble to form vesicles in methanol and organogels in aliphatic hydrocarbons. SEM, AFM, TEM, DLS, and fluorescence microscopy were all used to identify the structures of the vesicles. It was proposed that intermolecular pi stacking of the folded frameworks and hydrogen bonding of the amide units in the appended chains induced the molecules to produce cylindrical aggregates. In polar methanol, these aggregates packed together to generate one-layered vesicles owing to hydrophobically induced entanglement of the peripheral chains, while in nonpolar hydrocarbons, the peripheral chains entwined across stacked cylinders to form three-dimensional networks and thus immobilize the liquid molecules.
Hydrogen-bonded benzylidenebenzohydrazide macrocycles and oligomers: testing the robust capacity of an amide chain in promoting the formation of vesicles
摘要:
This Letter describes 2-(2-(dioctylamino)-2-oxoethyl-amino)-2-oxoethoxyl (DPAOE)-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 center dot center dot center dot 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. (C) 2010 Elsevier Ltd. All rights reserved.
Vesicles and Organogels from Foldamers: A Solvent-Modulated Self-Assembling Process
作者:Wei Cai、Gui-Tao Wang、Yun-Xiang Xu、Xi-Kui Jiang、Zhan-Ting Li
DOI:10.1021/ja801618p
日期:2008.6.1
Nonamphiphilic, hydrogen-bonded hydrazide foldamers appended with four or six long flexible chains were revealed to spontaneously assemble to form vesicles in methanol and organogels in aliphatic hydrocarbons. SEM, AFM, TEM, DLS, and fluorescence microscopy were all used to identify the structures of the vesicles. It was proposed that intermolecular pi stacking of the folded frameworks and hydrogen bonding of the amide units in the appended chains induced the molecules to produce cylindrical aggregates. In polar methanol, these aggregates packed together to generate one-layered vesicles owing to hydrophobically induced entanglement of the peripheral chains, while in nonpolar hydrocarbons, the peripheral chains entwined across stacked cylinders to form three-dimensional networks and thus immobilize the liquid molecules.
Hydrogen-bonded benzylidenebenzohydrazide macrocycles and oligomers: testing the robust capacity of an amide chain in promoting the formation of vesicles
作者:Ben-Ye Lu、Guang-Jun Sun、Jian-Bin Lin、Xi-Kui Jiang、Xin Zhao、Zhan-Ting Li
DOI:10.1016/j.tetlet.2010.05.076
日期:2010.7
This Letter describes 2-(2-(dioctylamino)-2-oxoethyl-amino)-2-oxoethoxyl (DPAOE)-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 center dot center dot center dot 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. (C) 2010 Elsevier Ltd. All rights reserved.