Self-Discriminating Termination of Chiral Supramolecular Polymerization: Tuning the Length of Nanofibers
Self-Discriminating Termination of Chiral Supramolecular Polymerization: Tuning the Length of Nanofibers
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DOI：
10.1002/anie.201500292
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发表时间：
2015-05-11
影响因子：
16.6
通讯作者：
Nakashima, Takuya
中科院分区：
文献类型：
--
作者：
Kumar, Jatish;Tsumatori, Hiroyuki;Nakashima, Takuya
在功能软材料的设计中，将超分子聚合导向优选的组织类型是极其重要的。本文提出了一种简单的方法，通过控制对映体过量（ee）来调节手性双色双萘形成的超分子聚合物的长度和光学手性。对映不纯的化合物产生了超过几微米的细纤维，而外消旋混合物则有利于形成纳米颗粒。热力学研究表明，杂手性组合优于同手性组合。杂手性结合比同手性结合更强，终止了纤维组合的伸长，从而导致非外消旋混合物中纤维长度的控制。由pi-pi相互作用驱动的超分子聚合突出了扭曲pi核的几何形状对这种自分类组装的影响。
Directing the supramolecular polymerization towards a preferred type of organization is extremely important in the design of functional soft materials. Proposed herein is a simple methodology to tune the length and optical chirality of supramolecular polymers formed from a chiral bichromophoric binaphthalene by the control of enantiomeric excess (ee). The enantiopure compound gave thin fibers longer than a few microns, while the racemic mixture favored the formation of nanoparticles. The thermodynamic study unveils that the heterochiral assembly gets preference over the homochiral assembly. The stronger heterochiral binding over homochiral one terminated the elongation of fibrous assembly, thus leading to a control over the length of fibers in the nonracemic mixtures. The supramolecular polymerization driven by pi-pi interactions highlights the effect of the geometry of a twisted pi-core on this self-sorting assembly.