RUI: Kinetic and Mechanistic Studies of Reactive Intermediates in Solution and Confined Environments.

RUI：溶液和受限环境中反应中间体的动力学和机理研究。

• 批准号: 0844110
• 负责人: Peter de Lijser
• 金额: $ 25.85万
• 依托单位: CSU Fullerton Auxiliary Services Corporation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0844110&HistoricalAwards=false
• 关键词: RUI; Kinetic; Mechanistic; Studies; Reactive

With support of the Organic Dynamics Program in the Chemistry Division, Professor Peter de Lijser's proposed research will provide kinetic and mechanistic information on structure and reactivity of high-energy intermediates formed in the photooxidation of oximes and related compounds. These reactive intermediates, oxime radical cations, and other reactive oxygen or nitrogen species derived from these, such as iminoxyl and iminoyl radicals, will be studied in solution as well as in a confined environment (zeolites) in order to provide extra stabilization for the reactive intermediates. The proposal's primary research goals are: 1)To investigate the structure-reactivity relationships of oxime radical cations. This will require the PI and his research group to find conditions to observe these reactive intermediates directly. Both aldoxime and ketoximes will be studied and the formation of nitriles from aldoximes is of specific interest. 2)To probe the structure-reactivity relationships of oxime ethers, specifically the hypothesis that these species undergo nucleophilic addition or substitution at nitrogen. The PI's efforts will be focused on intramolecular reactions. 3)To selectively generate and study iminoxyl and iminoyl radicals, which are the proposed intermediates in the photooxidation of ketoximes and aldoximes, respectively.Oximes and related compounds have found use as pesticides and drugs. Release of these chemicals into the environment (including cells and tissue of plants and higher animals) may result in photochemical (sensitized or direct) or enzymatic oxidations leading to the formation of reactive intermediates such as radical ions and radicals. The chemistry and potential dangers of these types of species are virtually unknown, and there exists a need for accurate kinetic and other reactivity data so that a general structure-reactivity pattern can be developed. The knowledge gained from these fundamental mechanistic and kinetic studies will establish a foundation for understanding experimental observations. The research will also provide much-needed tools to successfully utilize radical ions and other high-energy species for new chemical processes in synthesis and possibly in materials applications.The proposed research will also provide an outstanding educational experience for students. Students will learn basic chemical laboratory principles such as how to synthesize, purify, and characterize compounds by means of spectroscopic techniques. Additionally, they will receive a solid education in learning mechanistic methodologies and advanced problem skills. Students will also receive training in less traditional techniques and areas such as electrochemistry, computational chemistry and nanosecond transient absorption spectroscopy; the last will be achieved by means of the newly purchased laser flash photolysis instrumentation with funds from this award. Professor de Lijser continues to build on his track record for increasing involvement of undergraduate students in scientific activities. The Department of Chemistry and Biochemistry at California State University, Fullerton (CSUF) has long been recognized as offering a rigorous and contemporary curriculum that is responsive to future developments, reflects the interdisciplinary nature and diversity of the chemical science and enables students to become successful professionals, scholars, and scientifically literate citizens. Because the CSU provides a substantial percentage of the technical workforce, teachers and graduate student applicants in California, exposing students to modern research methods and environments will sustain regional, state-wide and national capabilities for education and training of undergraduates and Masters' students in the chemical sciences.

在化学系有机动力学计划的支持下，Peter de Lijser教授的拟议研究将提供关于在肟类和相关化合物的光氧化过程中形成的高能中间体的结构和反应的动力学和力学信息。为了给活性中间体提供额外的稳定性，我们将在溶液和受限环境(沸石)中研究这些活性中间体、肟基阳离子以及由此衍生的其他活性氧或氮物种，如亚氨氧基和亚氨基自由基。该方案的主要研究目标是：1)研究肟基阳离子的结构-活性关系。这将需要PI和他的研究小组找到条件来直接观察这些活性中间体。本课程将对乙醛和酮肟进行研究，并特别关注从乙醛肟生成腈的过程。2)探索肟醚的结构-活性关系，特别是这些物种在氮上发生亲核加成或取代的假设。PI的努力将集中在分子内反应上。3)选择性地合成和研究亚胺氧基和亚氨基自由基，这两种自由基分别是酮肟和缩醛肟光氧化反应的中间体，已被用作农药和药物。这些化学物质释放到环境中(包括植物和高等动物的细胞和组织)可能会导致光化学(敏化或直接)或酶催化氧化，从而形成活性中间体，如自由基离子和自由基。这些类型的物种的化学和潜在危险几乎是未知的，需要准确的动力学和其他反应性数据，以便可以开发出一般的结构-反应性模式。从这些基本的力学和动力学研究中获得的知识将为理解实验观测奠定基础。这项研究还将提供急需的工具，成功地利用自由基离子和其他高能物种在合成和可能的材料应用中进行新的化学过程。拟议的研究还将为学生提供出色的教育经验。学生将学习基本的化学实验室原理，如如何用光谱技术合成、提纯和表征化合物。此外，他们还将接受扎实的教育，学习机械方法和高级问题技能。学生还将接受不太传统的技术和领域的培训，如电化学、计算化学和纳秒瞬时吸收光谱；最后一项将通过新购买的激光闪光光解仪器实现，资金来自该奖项。De Lijser教授继续以他的记录为基础，让本科生更多地参与科学活动。加州州立大学富勒顿分校(CSUF)的化学和生物化学系长期以来一直被认为提供了严格和现代的课程，能够响应未来的发展，反映出化学科学的跨学科性质和多样性，并使学生成为成功的专业人员、学者和具有科学素养的公民。由于加州州立大学提供了加州相当大比例的技术劳动力、教师和研究生申请者，让学生接触现代研究方法和环境将保持地区、全州和全国教育和培训化学科学本科生和硕士学生的能力。