Nano-Containers for Novel Separations and Reactions

用于新型分离和反应的纳米容器

• 批准号: 1507344
• 负责人: Bruce Gibb
• 金额: $ 48万
• 依托单位: Tulane University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1507344&HistoricalAwards=false
• 关键词: Nano; Containers; Novel; Separations; Reactions

With this award, the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry is supporting Professor Bruce Gibb of Tulane University to develop new 'nano-containers' for applications in both chemical reactions and chemical separations. In the everyday world containers are utilized to store, transport, and separate items. Chemists also use containers (reaction flasks) to form new matter; mixing A and B gives new compound C; a new pharmaceutical, perhaps, a new coating material to prevent rusting in bridges and other infrastructure, or perhaps a new molecule for the next generation flat-screen OLED television. This project concerns very small containers. These nano-containers spontaneously form in water and possess inner-spaces approximately one-billionth the size of a small dust particle. As a result, when even the smallest of molecules is stored in these containers they constantly bump into the sides of the vessel. This leads to some very unusual chemical properties, of which two are being investigated: 1) Nano-containment can lead to new chemical reactivity, and consequently this program investigates some of the reactions that can occur within these containers to evaluate their overall properties; 2) New separation protocols are also possible, and with this in mind the purification of industrially important chemicals from complex mixtures is being investigated. Both the identification of new chemical reactions and the development of new, non-energy intensive separations have the potential for broader scientific impact across the chemical enterprise. This program of research will also provide research training for undergraduate and graduate students in both analytical and synthetic chemistry. This proposal has two related overall goals. Both concern the selective complexation of guest molecules within well-defined, nano-capsules formed by water-soluble cavitands. The first aim is to examine the ability of this family of hosts to act as phase-transfer catalysts for new and unusual chemical conversions. Early work has identified that these hosts bind reactive anions, including inorganic anions, and that these can be co-encapsulated with organic guests. Trapped within the yocto-liter volumes formed by these dimerized hosts, the two guests experience high effective molarity, relative to each other. Building on these points, the proposed studies utilize NMR and GC-MS to investigate the co-encapsulation of a range of reagents and substrates and hence bring about efficient, regioselective conversion processes that are catalytic in host. The second aim of this proposal is to use the observed selective guest-binding properties of these hosts to bring about the separation of complex mixtures of terpenoids and constitutionally isomeric hydrocarbons. The proposed plans examine the hosts as shape-selective phase-transfer catalysts in U- and W-tube experiments. NMR and GC-MS experiments are utilized to examine the performance of each host carrier for the different cases studied.

凭借这一奖项，化学学部的大分子、超分子和纳米化学项目将支持杜兰大学的Bruce Gibb教授开发新的“纳米容器”，用于化学反应和化学分离。在日常生活中，集装箱被用来储存、运输和分离物品。化学家也使用容器（反应烧瓶）来形成新物质；A和B混合得到新的化合物C；一种新的药物，一种防止桥梁和其他基础设施生锈的新涂层材料，或者一种用于下一代平板OLED电视的新分子。这个项目涉及非常小的容器。这些纳米容器在水中自发形成，其内部空间约为小尘埃颗粒的十亿分之一。因此，即使是最小的分子被储存在这些容器中，它们也会不断地撞到容器的侧面。这导致了一些非常不寻常的化学性质，其中两个正在研究中：1)纳米容器可以导致新的化学反应性，因此本项目研究了在这些容器中可能发生的一些反应，以评估它们的整体性质；新的分离方案也是可能的，考虑到这一点，人们正在研究从复杂混合物中提纯工业上重要的化学物质。新的化学反应的识别和新的、非能源密集型分离的发展都有可能对整个化工企业产生更广泛的科学影响。该研究项目还将为分析化学和合成化学的本科生和研究生提供研究培训。该提案有两个相关的总体目标。两者都关注客体分子在由水溶性空腔形成的定义良好的纳米胶囊内的选择性络合。第一个目的是研究这个宿主家族作为相转移催化剂的能力，以促进新的和不寻常的化学转化。早期的工作已经确定这些寄主结合活性阴离子，包括无机阴离子，并且这些阴离子可以与有机客体共封装。被困在这些二聚体宿主形成的千升体积中，两个客体相对于彼此经历了高的有效摩尔浓度。基于这些观点，本文提出的研究利用NMR和GC-MS来研究一系列试剂和底物的共包封，从而实现在宿主体内催化的高效、区域选择性转化过程。本建议的第二个目的是利用观察到的这些宿主的选择性客体结合特性来分离萜类化合物和构象异构体烃的复杂混合物。所提出的计划在U管和w管实验中检验了宿主作为形状选择性相转移催化剂。利用核磁共振和气相色谱-质谱实验来研究不同情况下每个宿主载体的性能。