State Key Lab for Supramolecular Structure and Materials, College of Chemistry, Jilin University , Changchun 130012, China.
J Am Chem Soc. 2014 Nov 19;136(46):16152-5. doi: 10.1021/ja510182x. Epub 2014 Nov 10.
The highlight of self-assembly is the reversibility of various types of noncovalent interactions which leads to construct smart nanostructures with switchable pores. Here, we report the spontaneous formation of inflatable nanofibers through the formation of hollow internal channels triggered by guest encapsulation. The molecules that form this unique nanofibers consist of a bent-shaped aromatic segment connected by a m-pyridine unit and a hydrophilic dendron at its apex. The aromatic segments self-assemble into paired dimers which stack on top of one another to form thin nanofibers with pyridine-functionalized aromatic cores. Notably, the nanofibers reversibly inflate into helical tubules through the formation of hollow cavities triggered by p-phenylphenol, a hydrogen-bonding guest. The reversible inflation of the nanofibers arises from the packing rearrangements in the aromatic cores from transoid dimers to cisoid macrocycles driven by the reversible hydrogen-bonding interactions between the pyridine units of the aromatic cores and the p-phenylphenol guest molecules.
自组装的突出特点是各种类型的非共价相互作用的可逆性,这导致了具有可切换孔的智能纳米结构的构建。在这里,我们报告了通过客体包封触发的中空内部通道的形成,自发形成可膨胀纳米纤维。形成这种独特纳米纤维的分子由通过 m-吡啶单元连接的弯曲形芳族片段和在其顶点处的亲水性树枝状分子组成。芳族片段自组装成成对的二聚体,这些二聚体彼此堆叠形成具有吡啶功能化芳核的薄纳米纤维。值得注意的是,纳米纤维通过 p-苯二酚(一种氢键供体)触发的中空腔的形成可逆地膨胀成螺旋管。纳米纤维的可逆膨胀是由芳核中从反式二聚体到顺式大环的构象重排引起的,这是由芳核的吡啶单元和 p-苯二酚客体分子之间的可逆氢键相互作用驱动的。