RUI: Phosphorus-Directed C-H Borylation and Reactivity of Phosphaboronates

在化学系化学催化项目的支持下，圣地亚哥大学的蒂莫西·克拉克教授正在研究过渡金属催化过程，该过程能够将硼选择性地引入含磷的有机分子中。还在研究允许用最终感兴趣的其他基团取代硼残留物的后续反应，其净目标是实现增值有机磷产品的制造。这些努力是重要的，因为硼基化和硼转化化学的基本进展是预期的，并且由于所产生的有机磷产品的种类的重要性，其具有作为药剂、农用化学品和具有广泛用途的其他先进材料的潜在应用。克拉克教授主要与圣地亚哥大学的本科生同事合作，因此，资助项目的更广泛影响将扩展到STEM（科学，技术，工程和数学）领域的年轻人的教育和培训。此外，一名从事该项目的博士后助理将接受PI的指导，以建立未来的研究和教学事业，从而进一步丰富科学和教育的人力资源库。资助的研究重点是显着扩大C-H硼基化化学的最新进展，以实现有价值的手性膦和膦酸酯的有效新路线。正在追求两个不同的目标，在烷基或芳基有机磷化合物的背景下探索这一主题。在目标1中，铱催化的烷基膦、膦酸酯和相关有机磷物种的C（sp3）-H硼基化反应在手性配体的存在下进行了研究，以实现仲烷基硼酸酯的对映选择性合成。将该化学与允许C-B键立体特异性转化为C-C或C-X（X = O，N）键的广泛反应范围进行排序，允许有利地合成有用的对映体富集的手性膦。在目标2中，正在探索通过新颖的氧化铜催化的同偶联和异偶联方法从芳基硼酸酯通过芳基膦酸酯的磷定向邻硼化形成联芳基。执行这种化学的机会，它提供了一个简洁的路线，一些重要类别的轴向手性双膦配体，在对映选择性models.This奖项反映了NSF的法定使命，并已被认为是值得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的支持。

With the support of the Chemical Catalysis Program in the Division of Chemistry, Professor Timothy Clark of the University of San Diego is studying transition metal-catalyzed processes that enable the selective introduction of boron into organic molecules that contain phosphorus. Subsequent reactions that allow for replacement of the boron residue with yet other groups of ultimate interest are also under investigation with the net aim of achieving the manufacture of value-added organophosphorus products. These endeavors are significant because of the fundamental advances to borylation and boron-conversion chemistry that are anticipated and due to the importance of the kinds of organophosphorus products being generated, which have potential applications as pharmaceutical agents, agrochemicals, and other advanced materials of broad utility. Professor Clark works primarily with undergraduate student coworkers at the University of San Diego and, accordingly, the broader impacts of the funded project will extend to the education and training of young people in STEM (science, technology, engineering and mathematics) fields. In addition, a post-doctoral associate working on the project will receive mentoring from the PI to build toward a future career in research and teaching thus further enriching the pool of human resources in science and education.The funded research is focused on significantly expanding recent advances in C–H borylation chemistry to enable efficient new routes to valuable chiral phosphines and phosphonates. Two distinct aims are being pursued that explore this theme in the context of either alkyl or aryl organophosphorus compounds. In Aim 1, iridium-catalyzed C(sp3)–H borylation of alkyl phosphines, phosphonates, and related organophosphorus species, is being investigated in the presence of chiral ligands to achieve an enantioselective synthesis of secondary alkyl boronates. Sequencing this chemistry with the expansive range of reactions that allow for the stereospecific conversion of C–B bonds into C–C or C–X (X = O, N) bonds allows for expedient syntheses of useful enantioenriched chiral phosphines. In Aim 2, biaryl formation from aryl boronates generated by phosphorus-directed ortho borylation of aryl phosphonates, is being explored via novel oxidative copper-catalyzed homo- and hetero-coupling processes. Opportunities for executing this chemistry, which offers a concise route to some important classes of axially chiral bisphosphine ligands, in an enantioselective modality are also under investigation.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.