Developing New Reactions and Catalysis via Designer Ligands for Organometallic Chemistry

通过有机金属化学设计配体开发新的反应和催化

• 批准号: RGPIN-2020-05076
• 负责人: Hayes, Paul
• 金额: $ 2.11万
• 依托单位: University of Lethbridge
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=748463
• 关键词: Developing; New; Reactions; Catalysis; via

My research program combines chemical synthesis, catalysis and polymerization to tackle meaningful fundamental and applied questions that are relevant to society. More specifically, the primary goal of my research is to prepare new and unusual metal-containing molecules to catalyze the synthesis of pharmaceuticals, agrochemicals, important chemical intermediates, fine chemicals and materials. From a pedagogical perspective, great emphasis is placed upon learning requisite laboratory techniques, the development of critical thinking and communication skills, and the ability to work in a safe and thoughtful manner. Over the next 5 years my research team will synthesize late transition metal complexes that are stabilized by designer NNN-pincer ligands. These species have been targeted as potential sources of reactive 14-electron, T-shaped intermediates, from which a wide range of catalytic pathways can be envisioned. Preliminary work has revealed that the hemilabile phosphinimine donors act cooperatively with the metal centre to activate various small molecules, including H2, CO and silanes. The products of these reactions will be studied to ascertain their competence in mediating a range of catalytic processes. For example, the silicon atom in our rhodium silylenes (LRh=SiR2) is expected to position substrates to facilitate the activation of challenging bonds, such as C-F. Installation of fluorine into organic molecules is important to the pharmaceutical industry as upwards of 30% of new drugs contain fluorine. Related complexes that bear multiple bonds between rhodium and germanium, tin and boron will also be prepared and their reaction chemistry explored in depth. Another direction in my laboratory will focus upon the preparation of phosphazide (R3P-(N3)-R) ligands, and metal complexes thereof. Because phosphazides are prone to loss of N2, their coordination chemistry is largely unrealized. However, the ease with which pendant groups can be fine-tuned, their coordinative versatility, and the ability for conversion to phosphinimines, suggests that phosphazides offer potential as ligands in inorganic chemistry and homogeneous catalysis. We will develop routes to stable, and thus, more easily studied phosphazide-containing ligands. Given the tendency of f-elements to accommodate high coordination numbers, they will be used for initial complexation studies.    In summary, this work has great potential for addressing issues currently confronting Canada (e.g. conversion of atmospheric N2 into agricultural products, new pharmaceuticals to combat disease), and developing new technologies that will improve the lives of Canadians. For example, the creation of methods for the direct installation of carbon, silicon and fluorine represents an efficient and cost-effective route to valuable organic molecules. Ultimately, this chemistry will afford new catalytic systems and provide valuable training to the next generation of scientists.

我的研究计划结合了化学合成，催化和聚合，以解决与社会相关的有意义的基础和应用问题。更具体地说，我研究的主要目标是制备新的和不寻常的含金属分子，以催化药物，农用化学品，重要的化学中间体，精细化学品和材料的合成。从教学的角度来看，非常重视学习必要的实验室技术，批判性思维和沟通技能的发展，以及以安全和周到的方式工作的能力。 在接下来的5年里，我的研究团队将合成后过渡金属配合物，这些配合物由设计师NNN-钳形配体稳定。这些物种已被作为潜在的活性14-电子，T形中间体，从中可以预见到广泛的催化途径的来源。初步工作表明，半不稳定的膦亚胺捐助者与金属中心合作，以激活各种小分子，包括H2，CO和硅烷。将研究这些反应的产物，以确定它们在介导一系列催化过程中的能力。例如，我们的铑亚甲硅烷基（LRh= SiR 2）中的硅原子预期定位衬底以促进具有挑战性的键（例如C-F）的活化。将氟安装到有机分子中对制药工业很重要，因为超过30%的新药含有氟。还将制备铑和锗、锡和硼之间具有多重键的相关络合物，并深入探讨其反应化学。我实验室的另一个方向将集中在磷腈（R3 P-（N3）-R）配体及其金属络合物的制备上。由于磷腈易于损失N2，因此它们的配位化学在很大程度上未实现。然而，侧基可以被微调的容易性，它们的配位多功能性，以及转化为膦亚胺的能力，表明磷腈在无机化学和均相催化中提供了作为配体的潜力。我们将开发稳定的路线，因此，更容易研究含磷酰亚胺配体。考虑到f-元素适应高配位数的趋势，它们将用于初始络合研究。 总之，这项工作对于解决加拿大目前面临的问题（例如将大气中的N2转化为农产品、防治疾病的新药物）和开发将改善加拿大人生活的新技术具有巨大潜力。例如，碳、硅和氟的直接安装方法的创建代表了获得有价值的有机分子的有效且具有成本效益的途径。最终，这种化学将提供新的催化系统，并为下一代科学家提供宝贵的培训。