Reaching New Horizons in Iminyl Radical Chemistry via Microwave Irradiation

通过微波辐射实现亚氨基自由基化学的新视野

基本信息

批准号：
1856530
负责人：
Steven Castle
金额：
$ 49.64万
依托单位：
Brigham Young University
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-08-01 至 2023-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1856530&HistoricalAwards=false
关键词：
Reaching New Horizons Iminyl Radical

项目摘要

With this award, the Chemical Synthesis Program of the NSF Division of Chemistry is supporting the research of Professor Steven L. Castle of Brigham Young University. Professor Castle is developing new methods for synthesizing organic molecules that are facilitated by microwave energy rather than by catalysts or reagents that are often toxic, hazardous, or expensive. In comparison to traditional organic synthesis techniques, these methods are providing safer, more sustainable, and more efficient routes to compounds that have potential application as pharmaceuticals. A key innovation is the use of microwaves to trigger cascade processes that convert simple precursors into complex and useful compounds by enabling a sequence of chemical transformations to occur in a controlled fashion. Professor Castle and his students are impacting STEM education by creating lesson plans that will assist high school chemistry teachers with incorporating organic chemistry into their courses. These plans are designed to inspire high school students to pursue STEM careers by exposing them to the exciting world of organic chemistry and teaching them about the positive impact that chemistry has on human health and quality of life.Professor Castle and his co-workers employ O-aryl oxime ethers as precursors of iminyl radicals. Upon irradiation with microwaves, these species undergo direct homolysis of the O-N bond. The resulting iminyl radicals are then transformed by either cyclization or hydrogen atom abstraction (i.e., C-H activation). In both cases, a radical intermediate is formed and subsequently trapped by a reagent that forges a new C-C, C-N, C-O, C-S, or C-X bond. By generating iminyl radicals under nonreducing conditions in the absence of metal catalysts or redox cycles, these reactions permit a wide range of functionalized radical traps to be used. Additionally, the cyclizations are stereoselective and can be incorporated into cascade processes. The utility of these microwave-based methods is being demonstrated through the efficient construction of a member of the securinega family of alkaloids. The student participants in this project are receiving training in experimental techniques, troubleshooting, communication, and critical thinking that will enable them to pursue careers in chemistry or other STEM fields.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.

有了这个奖项，NSF化学部的化学合成计划支持杨百翰大学的史蒂文·L·卡斯尔教授的研究。 Castle教授正在开发合成微波能量促进的有机分子的新方法，而不是通过催化剂或通常是有毒，有害或昂贵的催化剂或试剂。与传统的有机合成技术相比，这些方法为具有潜在应用的药物应用的化合物提供了更安全，更可持续和更有效的途径。一个关键的创新是使用微波来触发级联进程，这些过程通过使一系列化学转化以受控方式发生，将简单的前体转化为复杂而有用的化合物。 Castle教授和他的学生正在通过制定课程计划来影响STEM教育，以帮助高中化学老师将有机化学融入他们的课程中。这些计划旨在激发高中生通过将STEM职业暴露于令人兴奋的有机化学世界，并教给他们有关化学对人类健康和生活质量的积极影响的教导。professorCastle及其同事将O-Aryl Oxime Ethers用作iminyl激素的前体。在用微波辐射时，这些物种会直接对O-N键同伊。然后，通过环化或氢原子抽象（即C-H激活）转化所得的亚氨基自由基。在这两种情况下，都形成了自由基中间体，然后被一种试剂捕获，该试剂伪造了新的C-C，C-N，C-O，C-S或C-X键。通过在没有金属催化剂或氧化还原周期的情况下，在非还原条件下产生亚氨基自由基，这些反应允许使用广泛的功能化自由基陷阱。此外，环化是立体选择性的，可以将其纳入级联过程中。这些基于微波炉的方法的实用性正在通过有效地构造生物碱家族的成员来证明。该项目的学生参与者正在接受实验技术，故障排除，沟通和批判性思维的培训，这将使他们能够从事化学或其他STEM领域的职业。这项奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛的影响审查标准来通过评估来支持的。