New Reactivity Pathways Using Pincer Ligands with Central Lewis Acidic Sites

使用具有中心路易斯酸性位点的钳配体的新反应途径

• 批准号: 2102324
• 负责人: Oleg Ozerov
• 金额: $ 50万
• 依托单位: Texas A&M University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-06-01 至 2025-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2102324&HistoricalAwards=false
• 关键词: New; Reactivity; Pathways; Using; Pincer

With funding from the Chemical Synthesis Program in the Chemistry Division, Professor Oleg Ozerov at the Department of Chemistry at Texas A&M University (TAMU) will selectively modify chemical bonds in nitrogen-containing organic molecules, called nitrogen-containing heterocycles. The efficient preparation and further modification of the nitrogen-containing heterocycles frequently is necessary in the industrial production of many pharmaceuticals and agrochemicals. However, the processes that are presently used for these transformations are often inefficient and do not exactly target the chemical bonds that must be manipulated. To rectify this problem, frameworks containing metal atoms bonded to boron or aluminum atoms are constructed. The boron or aluminum atoms can capture a nitrogen atom and hold the nitrogen-containing heterocycle in a very controlled geometry that allows the metal atom to activate specific chemical bonds. This permits precise control of the nitrogen-containing heterocycle. The project involves a network of collaborators, including Professor Anna Larsen at Ithaca College and Assistant Professor Miles Johnson at the University of Richmond, both faculty at primarily undergraduate institutions. The project also aims to increase the participation of students from underrepresented groups through graduate student recruitment efforts and outreach with the local secondary schools.The theme of this project involves the synergistic use of the Lewis acidity of boryl or aluminyl sites bonded to transition metals and incorporated into pincer type ligands. It exploits the ability of boryl or an aluminyl units to capture the nitrogenous group in an azine substrate. This positions the transition metal to activate a specific C-H bond, which is topologically distinct from traditional C-H activation approaches. To develop a library of new ligands, 1,2-pyrrolediyl will be utilized as a key building block in the synthesis of pincer type ligands that contain the boryl or aluminyl moieties. Using these ligands, rhodium, iridium, and ruthenium complexes will be prepared and their ability to activate C-H bonds will be investigated. The mechanistic roles of B or Al in shuttling organic fragments to and from the transition metal and their involvement in the C-H activation process will be probed. Finally, the catalytic functionalization of azines and related substrates will be developed. The proposed research involves interactions with two PUI collaborators, Dr. Larsen (Ithaca College) and Dr. Johnson (U. of Richmond), and will proceed via close connections between TAMU graduate student mentors and Ithaca College and University of Richmond undergraduates.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.

在化学部门化学合成项目的资助下，德克萨斯农工大学化学系（TAMU）的奥列格·奥泽罗夫教授将选择性地修饰含氮有机分子中的化学键，称为含氮杂环。在许多药品和农用化学品的工业生产中，含氮杂环化合物的高效制备和进一步改性往往是必要的。然而，目前用于这些转化的过程通常效率低下，并且不能精确地针对必须操纵的化学键。为了纠正这个问题，构建了包含金属原子与硼或铝原子结合的框架。硼原子或铝原子可以捕获一个氮原子，并将含氮杂环保持在一个非常可控的几何形状，从而允许金属原子激活特定的化学键。这样就可以精确地控制含氮杂环。该项目涉及合作者网络，包括伊萨卡学院的安娜·拉森教授和里士满大学的助理教授迈尔斯·约翰逊，他们都是主要本科院校的教员。该项目还旨在通过研究生招生工作和与当地中学的联系，增加代表性不足群体学生的参与。这个项目的主题涉及到与过渡金属结合的硼基或铝基位点的刘易斯酸度的协同使用，并将其纳入钳形配体中。它利用硼基或铝基单元捕获氮基在氮基底物中的能力。这使得过渡金属可以激活一个特定的碳氢键，这在拓扑结构上与传统的碳氢激活方法不同。为了开发新的配体库，1,2-吡咯二基将被用作合成含有硼基或铝基基团的钳形配体的关键构建块。利用这些配体，铑、铱和钌配合物将被制备，并将研究它们激活C-H键的能力。B或Al在有机碎片与过渡金属之间穿梭的机制作用以及它们在碳氢活化过程中的参与将被探讨。最后，对氮类化合物及其相关底物的催化功能化进行了研究。拟议的研究涉及与两位PUI合作者，Larsen博士（伊萨卡学院）和Johnson博士（里士满大学）的互动，并将通过TAMU研究生导师与伊萨卡学院和里士满大学本科生之间的密切联系进行。该奖项反映了美国国家科学基金会的法定使命，并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，被认为值得支持。

项目成果

Distinct modes of Si–H binding to Rh in complexes of a phosphine-diarylamido-silane (SiNP) pincer ligand

膦-二芳基酰胺-硅烷 (SiNP) 钳配体复合物中 Si–H 与 Rh 结合的不同模式

• DOI: 10.1039/d2dt02175g
• 发表时间: 2022
• 期刊: Dalton Transactions
• 影响因子: 4
• 作者: Rain Talosig, A.;Cosio, Mario N.;Morse, Benjamin;Nguyen, Vinh T.;Kosanovich, Alex J.;Pell, Christopher J.;Li, Chun;Bhuvanesh, Nattamai;Zhou, Jia;Larsen, Anna S.
• 通讯作者: Larsen, Anna S.