Merging Nanoparticle and Capsule Single Electron Transfer Catalysis

自然界在生物合成中经常使用激进的过程。虽然各种辅助因子被用来启动单电子转移（SET），但蛋白质框架与传统的离子酶机制起着完全不同的作用——控制固有的活性物质，而不是激活通常稳定的实体。最近，Lusby小组发现了一种新的主客体化学方法，其中固有极化的Pd2L4笼结构使用多个弱氢键封装客体。我们还发现，结合“激活”了弱氧化的醌，如氯胺，因此它们催化了各种基于set的反应（[4+2]，[2+2]环加成等），而未结合的醌则没有观察到。这个项目提出了一些挑战和机遇。金属纳米颗粒以前还没有被配位组件功能化，因此控制多配体的表面覆盖等问题可能是成功的关键。然而，凯开发的表面改性方法将促进这一雄心勃勃的探索性科学我们还预计胶囊微环境可以调整以影响正向和反向SET，从而影响反应性，而限制也将在控制区域和/或灾难选择性方面发挥关键作用。

Nature frequently uses radical processes in biosynthesis. While various co-factors are employed to initiate single electron transfer (SET), the protein framework plays a quite different role to conventional ionic enzyme mechanisms - controlling inherently reactive species rather than activating normally stable entities. Recently, the Lusby group uncovered a novel approach to host-guest chemistry wherein an inherently polarised Pd2L4 cage structure encapsulates guests using multiple weak H-bonds. We have also found that binding "activates" weakly-oxidising quinones, such as chloranil, so that they catalyse various SET-based reactions ([4+2], [2+2] cycloadditions etc.) not observed for the unbound quinones.This project presents several challenges and opportunities. Metal nanoparticles have not previously been functionalised with coordination assemblies, therefore issues such as controlling surface coverage of multitopic ligands will likely be key to success. However, the surface modification methodology developed by Kay will facilitate this ambitious exploratory science.4 We also anticipate that the capsule microenvironment can be tuned to affect both forward and reverse SET and hence reactivity, while the confines will also play a key role in controlling regio and/or diastreoselectivity.