CAREER: Chemoselective Functionalization of Strong C-O, C-F and C-H Bonds Using Boron Chemistry

职业：利用硼化学对强 C-O、C-F 和 C-H 键进行化学选择性功能化

• 批准号: 2239556
• 负责人: Florence Williams
• 金额: $ 65万
• 依托单位: University of Iowa
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2028-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2239556&HistoricalAwards=false
• 关键词: CAREER; Chemoselective; Functionalization; Strong; Bonds

With the support of the Chemical Synthesis Program in the Division of Chemistry and the Established Program to Stimulate Competitive Research (EPSCoR), Florence Williams of the University of Iowa is studying the ability of simple boron-containing reagents to deconstruct chemical compounds in useful ways to create value-added materials and/or to tackle contemporary environmental challenges. The research focuses on cleavage of chemical bonds that are ubiquitous in types of materials commonly used in medicine, agriculture, engineering, and commerce. During the course of these transformations, the key boron reagents are themselves degraded into innocuous boric acid – a low toxicity chemical found in household products such as laundry detergent. The methodology developed will be evaluated in a variety of important contexts, including: (1) for the controlled deconstruction (depolymerization) of epoxy resin plastics, which are not currently recycled, and (2) for the breakdown of per- and poly-fluoroalkyl substances (PFAS), which have arisen as persistent pollutants that cause significant health concerns. In addition to offering anticipated technological advancements in the areas of plastics recycling and PFAS remediation, the broader impacts of the funded project extend to the benefits accrued to society as Dr. Williams and her coworkers engage in a variety of activities to improve access to chemical education and to enhance the diversity, equity, and inclusion landscape at the University of Iowa. For example, continued development of a widely available smart phone-based app to facilitate undergraduate student learning in introductory organic chemistry courses is in progress and Dr. Williams is spearheading the creation of an American Chemical Society Women Chemist's Committee (ACS WCC) chapter at her institution. Taken together, these initiatives are anticipated to make the science of chemistry more accessible and inclusive to a diverse population of students and to increase general engagement in important organic chemistry-related topics.Under this award, the Williams team at the University of Iowa will focus on the development of boron-mediated reactions for the functionalization of traditionally inert C–O, C¬–F, and C–H bonds and the demonstration and evaluation of these processes in complex molecular settings. The work builds on insights gained from earlier findings of the Williams laboratory which revealed the tunability of boron trihalide-mediated C–F and C–O bond cleavage reactions and successful application of the latter to lignocellulose polymer separation. New research is designed to expand understanding of the key parameters driving chemoselectivity in both C–F and C–O cleavage contexts, to explore novel (radical-based) mechanisms of reactivity that expand into C–H functionalization, and to evaluate the potential of these reactions for the aforementioned degradation of PFAS and epoxy resin plastics. A design of experiments (DoE) approach will be employed to reveal mechanistic and operational nuances not previously appreciated for the chemo- and regio-selective cleavage of ethereal bonds. Finally, it is noted that undergraduate and graduate students working on the funded project will receive educational and experimental training preparing them to make significant future contributions to the Nation's STEM (science, technology, engineering and mathematics) workforce.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在化学系化学合成计划和刺激竞争研究既定计划 (EPSCoR) 的支持下，爱荷华大学的 Florence Williams 正在研究简单的含硼试剂以有用的方式解构化合物的能力创造增值材料和/或应对当代环境挑战 该研究重点是医学、农业、工程和工业领域常用材料类型中普遍存在的化学键断裂。在这些转化过程中，关键的硼试剂本身会降解成无害的硼酸——一种在洗衣粉等家用产品中发现的低毒性化学物质。所开发的方法将在各种重要环境中进行评估，包括：（ 1) 用于目前未回收的环氧树脂塑料的受控解构（解聚），以及 (2) 用于分解全氟烷基物质和多氟烷基物质 (PFAS)，这些物质是随着除了在塑料回收和 PFAS 修复领域提供预期的技术进步外，威廉姆斯博士和她的同事还参与了各种活动，为社会带来了更广泛的影响。例如，爱荷华大学正在继续开发一款广泛使用的基于智能手机的应用程序，以促进本科生学习有机化学入门课程。正在进行中并且威廉姆斯博士在她的机构中带头创建了美国化学会女性化学家委员会 (ACS WCC) 分会，这些举措预计将使化学科学更容易为不同的学生群体所接受和包容，并增加化学科学的影响力。普遍参与重要的有机化学相关主题。根据该奖项，爱荷华大学的威廉姆斯团队将专注于开发硼介导的反应，以实现传统惰性 C-O、C-F 和 C- 的功能化。 H债券及论证评价这项工作建立在威廉姆斯实验室早期发现的基础上，该发现揭示了三卤化硼介导的 C-F 和 C-O 键裂解反应的可调性，以及后者在木质纤维素聚合物分离中的成功应用。新研究旨在扩大对 C-F 和 C-O 裂解环境中驱动化学选择性的关键参数的理解，探索扩展到 C-H 的新型（基于自由基的）反应机制。功能化，并评估这些反应对上述 PFAS 和环氧树脂塑料降解的潜力，将采用实验设计 (DoE) 方法来揭示化学和区域选择性裂解的机械和操作细微差别。最后，值得注意的是，从事该资助项目的本科生和研究生将接受教育和实验培训，为他们未来为国家的 STEM（科学、技术、工程和数学）做出重大贡献做好准备。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。