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.

化学系的大分子、超分子和纳米化学项目获得该奖项，以支持杜兰大学的Bruce Gibb教授开发用于化学反应和化学分离的新型“纳米容器”。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；将A和B混合得到新的化合物C；一种新的药物，也许是一种防止桥梁和其他基础设施生锈的新涂层材料；或者可能是下一代平板OLED电视的新分子。这个项目涉及非常小的容器。这些纳米容器自发地在水中形成，内部空间大小约为微小尘埃颗粒的十亿分之一。因此，即使是最小的分子储存在这些容器中，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，其中两个正在被研究：1)纳米容器可以导致新的化学反应，因此本计划研究这些容器中可能发生的一些反应，以评估它们的整体性能；2)新的分离方案也是可能的，考虑到这一点，正在研究从复杂混合物中提纯具有工业重要性的化学品。新化学反应的识别和新的、非能源密集型分离的开发都有可能在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。这项提议有两个相关的总体目标。两者都涉及到客体分子在由水溶性空洞形成的定义明确的纳米胶囊中的选择性络合。第一个目标是考察这一系列主体作为相转移催化剂的能力，以进行新的和不寻常的化学转化。早期的工作已经确定，这些宿主结合了反应性阴离子，包括无机阴离子，并且这些阴离子可以与有机客体共包裹。被困在这些二聚化的宿主形成的Yocto-L体积中，两位客人体验到了相对于对方的高有效摩尔浓度。基于这一点，本研究利用核磁共振和GC-MS研究了一系列试剂和底物的共包裹，从而实现了高效的、区域选择性的、在宿主中具有催化作用的转化过程。这项建议的第二个目的是利用观察到的这些主体的选择性客体结合性质来实现对萜类化合物和构成异构体碳氢化合物的复杂混合物的分离。所提出的方案在U型和W型管实验中考察了作为择形相转移催化剂的主体。利用核磁共振和GC-MS实验考察了每种载体在不同情况下的性能。