New multifunctional ligation strategies for tuning transition metal reactivity

用于调节过渡金属反应性的新型多功能连接策略

• 批准号: 312624-2008
• 负责人: Turculet, Laura
• 金额: $ 2.7万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=481355
• 关键词: New; multifunctional; ligation; strategies; tuning

As stated by the 2007 Priestley Medalist, George M. Whitesides, "almost everything in chemistry is catalyzed." Transition metal catalysts in particular have risen to the challenge of providing solutions for many of the problems of modern synthetic chemistry, specifically with respect to the development of new chemical processes that convert abundant resources into value-added products in an efficient, selective, and environmentally friendly manner. The impact of transition metal catalysis was recognized in the awarding of the 2001 and 2005 Nobel Prizes in Chemistry. The development of such reactive catalysts represents an ongoing challenge that spans a range of chemical disciplines (e.g. organic, inorganic, environmental). Notably, all such breakthroughs are rooted in the fundamental study of transition metal reactivity. In this context, research in the Turculet group targets the preparation of reactive transition metal complexes that exhibit new and/or improved reactivity properties by virtue of their unique construction. Key to this endeavor is the design and synthesis of new ancillary ligands that impart novel structural and electronic characteristics to the ensuing metal complexes. The proposed research seeks to develop the metal chemistry of new ancillary 'pincer'-type ligands that feature previously under-explored, formally anionic heavier main group element donors (e.g. Si, P). Overarching questions that we seek to address in this research include: (i) Can such pincer complexes be prepared, and do they exhibit new or unusual reactivity properties? (ii) Does the replacement of traditionally employed anionic donors (e.g. C, N) with their heavier congeners (e.g. Si, P) in such complexes provide improved reactivity in established catalytic reactions (e.g. transfer hydrogenation)? (iii) Can electron-rich complexes featuring such 'heavier-element' pincer ligands mediate challenging bond activation reactions (e.g. N2, C-H) that are of fundamental importance for the utilization of abundant but unreactive resources? These studies will advance our understanding of how metal-ligand interactions influence reactivity, enabling the design of metal catalysts that can mediate new and increasingly challenging substrate transformations.

正如2007年的普利斯特利奖牌获得者乔治·M·怀特赛兹所说：“化学中几乎所有的东西都是催化的。”尤其是过渡金属催化剂面临着为现代合成化学中的许多问题提供解决方案的挑战，特别是在开发新的化学工艺方面，这些新工艺以高效、选择性和环境友好的方式将丰富的资源转化为增值产品。在2001年和2005年诺贝尔化学奖的颁发中，过渡金属催化的影响得到了认可。这类活性催化剂的开发是一项持续不断的挑战，涉及一系列化学学科(如有机、无机、环境)。值得注意的是，所有这些突破都植根于过渡金属反应性的基础研究。在此背景下，Turculet小组的研究目标是制备具有反应性的过渡金属络合物，这些络合物凭借其独特的结构表现出新的和/或改进的反应性能。这一努力的关键是设计和合成新的辅助配体，使随后的金属络合物具有新颖的结构和电子特性。这项拟议的研究旨在开发新的辅助性“钳形”型配体的金属化学，这些配体以前未被充分开发，形式上是阴离子较重的主族元素施主(例如，Si，P)。我们在这项研究中试图解决的主要问题包括：(I)能否制备这样的钳形复合体，以及它们是否具有新的或不寻常的反应性能？(2)在这类络合物中用其较重的同系物(如硅、磷)取代传统使用的阴离子给体(如C、N)是否可提高已建立的催化反应(如转移加氢)中的反应性？(Iii)具有这种“较重元素”钳形配体的富含电子的络合物能否调解具有挑战性的键活化反应(例如，N_2，C-H)，这些反应对于利用丰富但无反应的资源是至关重要的？这些研究将促进我们对金属-配体相互作用如何影响反应活性的理解，使金属催化剂的设计能够中介新的和日益具有挑战性的底物转化。