State Key Lab of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Changchun 130012 , China.
J Am Chem Soc. 2019 Mar 13;141(10):4182-4185. doi: 10.1021/jacs.8b12777. Epub 2019 Feb 26.
The chemical reactivity of molecules can be significantly enhanced when they are trapped in a confined space. Although such a confinement effect can be found in many self-assembled nanostructures, dissipation after completing the reaction to release the product remains elusive. Here we report substrate-directed transient self-assembly for accelerating a chemical reaction and spontaneous disassembly with releasing the products. The hydrophobic substrates mediate self-assembly of a dissolved pyridine-based amphiphile to provide a confined space to promote an aromatic nucleophilic substitution (SAr) reaction in water. The chemical reaction triggers disassembly of the aggregates with simultaneous release of the product that can be spontaneously separated out of the solution by precipitation. Neutralization of the amphiphilic molecule leads to a new cycle of self-assembly entrapping substrates and disassembly with releasing the product.
当分子被限制在一个封闭的空间中时,它们的化学反应性可以显著增强。尽管这种限制效应可以在许多自组装的纳米结构中找到,但在完成反应以释放产物后,这种限制效应仍然难以捉摸。在这里,我们报告了一种基于底物的瞬态自组装,用于加速化学反应并自发地进行解组装以释放产物。疏水性基底介导溶解的基于吡啶的两亲分子的自组装,为促进芳香亲核取代 (SAr) 反应提供了一个受限空间。化学反应引发了聚集物的解组装,同时释放出产物,产物可以通过沉淀自发地从溶液中分离出来。两亲分子的中和导致了一个新的循环,其中包含了底物的自组装、解组装和产物的释放。