Increasing the Electrophilicity at Boron via Carborane Substituents

通过碳硼烷取代基增加硼的亲电性

• 批准号: 2349851
• 负责人: Caleb Martin
• 金额: $ 57.5万
• 依托单位: Baylor University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-06-01 至 2027-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2349851&HistoricalAwards=false
• 关键词: Increasing; Electrophilicity; Boron; via; Carborane

With the support of the Chemical Synthesis program in the Division of Chemistry, Caleb Martin and his research team at Baylor University will study the synthesis of strong boron Lewis acids that feature non-conventional electron withdrawing substituents. Strong Lewis acids are essential to many important catalytic industrial and laboratory processes. Currently, boron compounds that contain fluorine are used in these reactions. However, there are pending Environmental Protection Agency mandates that will restrict the use of fluorine containing reagents that are set to begin 2025. Thus, replacements for the current boron-fluorine catalysts are essential. This project will develop an alternative to fluorine for boron-based catalysts for bond activation chemistry. This project also involves efforts to engage homeless high school students to stimulate their interest in science fields. Additionally, an annual advanced instrumentation workshop will host students and faculty from local small colleges.In this project, the Martin research team will synthesize boranes that feature icosahedral carborane clusters as electron withdrawing groups. A goal is to obtain boranes whose Lewis acidity is enhanced over that of their fluoroaryl counterparts. This enhancement will reflect electronic effects of the carborane substituent as well as the impact of carborane steric profiles upon the Lewis acid properties of these new boron-centered systems. The bulk and Lewis acidity of tris(ortho-carboranyl)borane will be investigated in frustrated Lewis pair chemistry. The other target, bis(1-methyl-ortho-carboranyl)borane, features a highly polar B-H bond. The reactivity of this bond as well as the stability of aryl variants will be studied. The proposed work will investigate the reactivity and properties of the newly synthesized borane Lewis super-acids. If successfully, the development of such new classes of non-fluorine-based boron-centered Lewis acids, could have a broad impact on synthetic and mechanistic chemistry, with implications for sustainable chemistry.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.

在化学系化学合成项目的支持下，贝勒大学的Caleb Martin和他的研究团队将研究具有非常规吸电子取代基的强硼刘易斯酸的合成。强刘易斯酸对许多重要的催化工业和实验室过程是必不可少的。目前，在这些反应中使用含氟的硼化合物。然而，环境保护局的授权将限制含氟试剂的使用，这些授权将于开始2025年开始。因此，必须更换目前的硼-氟催化剂。该项目将开发一种替代氟的硼基催化剂，用于键活化化学。该项目还包括努力让无家可归的高中生参与，以激发他们对科学领域的兴趣。此外，每年一次的先进仪器研讨会将接待来自当地小学院的学生和教师。在这个项目中，马丁研究小组将合成具有二十面体碳硼烷簇作为吸电子基团的硼烷。一个目标是获得其刘易斯酸性增强超过其氟芳基对应物的硼烷。这种增强将反映电子效应的碳硼烷取代基，以及碳硼烷立体配置文件后的刘易斯酸性能的影响，这些新的硼为中心的系统。在阻挫刘易斯对化学中研究了三（邻碳硼烷基）硼烷的体相和刘易斯酸性。另一个目标，双（1-甲基-邻-碳硼烷基）硼烷，具有高极性的B-H键。将研究该键的反应性以及芳基变体的稳定性。本论文的工作主要是研究新合成的硼烷类刘易斯超强酸的反应活性和性质。如果成功的话，这种新型的非氟基硼中心刘易斯酸的开发，可能会对合成和机械化学产生广泛的影响，并对可持续化学产生影响。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。