Regioselective Control of Multiple Additions to Empty and Endohedral Fullerenes

在化学系大分子、超分子和纳米化学(MSN)计划的支持下，德克萨斯大学埃尔帕索分校的Luis Echegoyen教授和他的研究团队将制备和表征面体内的“簇状富勒烯”，作为高效有机太阳能电池(OSCs)的受体材料。内面体簇富勒烯是一种碳笼，它捕获了各种簇合物，导致了不寻常的电子性质。最重要的是被包裹的团簇的性质和外面体碳表面上相应的添加位置之间的相互作用。长程目标是以预定的方式控制这些富勒烯表面上多个加成的区域化学。这个团队将使用独立的多重加成过程以及连接的过程来探索反应区域化学，其中加合物试剂通过定义明确的间隔子连接。这些化合物的性质将使用广泛的技术进行表征，包括X射线晶体分析、光谱和电化学，特别是寻找内外簇笼相互作用的证据及其与化合物整体化学和电子性质的关系。本项目主要关注两类面体内簇合物富勒烯，三金属氮化物，其中碳笼包裹M3n团簇，以及二金属硫化物，包裹M2s团簇。将致力于主要捕获过渡金属，避免稀土，包括混合金属硫化物M1M2S@C2n，其中M1和M2以及过渡金属和n39。本课程将充分探讨其内在和化学性质。一项外展计划将继续影响中学生，主要是西班牙裔八年级学生，让他们接触到能源和纳米概念和实验室实践。除了这一重要的更广泛的影响外，化合物和准备的材料，特别是在OSC中制备的化合物和材料，以及为参与该项目的学生提供的培训，还有潜在的社会益处，其中许多学生来自拉美裔背景。由于Echegoyen教授积极参与了与世界各地许多科学家的国际合作，这些丰富的智力互动产生了额外的更广泛的影响。

With support from the Macromolecular, Supramolecular, and Nanochemistry (MSN) Program of the Chemistry Division, Prof. Luis Echegoyen and his research team at the University of Texas at El Paso will prepare and characterize endohedral "clusterfullerenes", for potential uses as acceptor materials in high efficiency organic solar cells (OSCs). Endohedral clusterfullerenes are carbon cages that entrap a variety of clusters, resulting in unusual electronic properties. Of fundamental importance will be the interplay between the properties of the encapsulated clusters and the corresponding addition positions on the exohedral carbon surfaces. The long range goal is to control, in a predetermined way, the regiochemistry of multiple additions on the surfaces of these fullerenes. This team will explore reaction regiochemistry using independent multiple addition processes as well as tethered ones, where the adduct reagents are connected by a well-defined spacer. The properties of these compounds will be characterized using a wide variety of techniques, including X-ray crystallographic analyses, spectroscopy and electrochemistry, specifically looking for evidence of endo-exo cluster-cage interactions and their relationship to the overall chemical and electronic properties of the compounds.This project focuses mainly on two families of endohedral clusterfullerenes, the trimetallic nitrides, in which the carbon cages encapsulate M3N clusters, and the dimetallic sulfides, which entrap M2S clusters. Efforts will be devoted to entrapping mainly transition metals and avoid rare earths, including mixed metallic sulfides, M1M2S@C2n, where M1 and M2 and transition metals and n39. Intrinsic as well as chemical properties will be fully explored. An outreach program will continue to impact middle school students, primarily eighth graders of Hispanic origin, by exposing them to Energy and Nano concepts and laboratory practices. Besides this important broader impact there are potential societal benefits to be derived from the compounds and materials prepared, especially in OSCs, and from the training provided to the students involved in the project, many of whom are from Hispanic backgrounds. Because Professor Echegoyen is heavily involved in international collaborations with many scientists around the world, an additional broader impact results from these fertile intellectual interactions.