Reactive intermediates in zeolites and solution

沸石和溶液中的反应中间体

• 批准号: 203292-2009
• 负责人: Cozens, Frances
• 金额: $ 1.97万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2009
• 资助国家: 加拿大
• 起止时间: 2009-01-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=423944
• 关键词: Reactive; intermediates; zeolites; solution

A major goal of our research program is to obtain quantitative information about the effect of zeolite structure and composition on the behaviour of organic reactive intermediates using fast reaction techniques. In these studies, the short-lived reactive intermediates are generally utilized as probe molecules specially designed to give information about the nature of the internal cavities of zeolites. Zeolites are crystalline aluminosilicate materials made up of an open framework structure that gives rise to a variety of different cavities and channels. The overall objective is to determine how simple modifications to the zeolite structure and composition, such as alkali-metal cation exchange or the incorporation of co-reactants affect the dynamics of a variety of reactions involving short-lived species. One current focus is to study the dynamics of bimolecular reactions within zeolites using both carbenes and carbocations as probe reactive intermediates. The information from these studies will help to describe the diffusion of molecules within these solid systems. We are also obtaining results that will allow us to develop theories to explain why reactions in zeolites tend to show reduced substituent effects compared to the same reactions in solution. In addition, we are also exploring the potential utility of zeolites as hosts for two-photon absorption, a technique with great potential for a wide range of applications, including data storage and photodynamic therapies. Finally, we are taking advantage of our past experience studying the ionization of beta-substituted radicals in order to develop a new class of phototriggers that could be of use in studies of biological phenomena. State-of-the-art instruments are used in this research, including nanosecond and femtosecond lasers. Researchers become highly proficient in a wide range of experimental techniques including laser flash photolysis, complex data analysis, synthetic organic chemistry, and characterization techniques such as NMR, GC/MS, fluorescence and UV-Vis spectroscopy. The proposed research will train researchers to understand the complexity of modern experimental research using state-of-the-art equipment and will prepare those researchers for a strong scientific career.

我们研究计划的一个主要目标是利用快速反应技术获得有关沸石结构和组成对有机反应中间体行为影响的定量信息。在这些研究中，短寿命的反应中间体通常被用作探针分子，专门用于提供有关沸石内腔性质的信息。沸石是晶体铝硅酸盐材料，由一个开放的框架结构组成，产生各种不同的腔和通道。总体目标是确定沸石结构和组成的简单修饰，如碱金属阳离子交换或共反应物的掺入如何影响涉及短寿命物种的各种反应的动力学。目前的一个重点是研究沸石内的双分子反应动力学，同时使用碳烯和碳阳离子作为探针反应中间体。来自这些研究的信息将有助于描述这些固体系统中分子的扩散。我们还获得了一些结果，这些结果将使我们能够发展理论来解释为什么沸石中的反应与溶液中的反应相比，取代基效应倾向于降低。此外，我们也在探索沸石作为双光子吸收载体的潜在效用，这是一种具有广泛应用潜力的技术，包括数据存储和光动力治疗。最后，我们正在利用我们过去研究β取代自由基电离的经验，以开发一类新的光触发物，可用于研究生物现象。在这项研究中使用了最先进的仪器，包括纳秒和飞秒激光器。研究人员高度精通各种实验技术，包括激光闪光光解，复杂数据分析，合成有机化学和表征技术，如NMR， GC/MS，荧光和UV-Vis光谱。拟议的研究将训练研究人员了解使用最先进设备的现代实验研究的复杂性，并将为这些研究人员的科学事业做好准备。