Rhodium-catalysed intermolecular hydroacylation

铑催化的分子间加氢酰化

• 批准号: 2124619
• 金额: --
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2124619
• 关键词: Rhodium; catalysed; intermolecular; hydroacylation

My project will concentrate on the catalyst and catalytic cycle in the rhodium-catalysed hydroacylation reaction. This project sits on the boundary between organic and inorganic chemistry and is suitably funded equally by both. During the process of hydroacylation, the carbonyl C-H bond on an aldehyde compound is broken via oxidative addition onto a catalytic metal centre and a new C-C bond with alkene or alkyne substrate is formed. This is particularly interesting to synthetic chemists as the reaction is inherently atom efficient and a useful pathway to C-C bond formation. There are many examples of transition metal catalysed hydroacylation but rhodium catalysis is currently the most prolific. Rhodium-catalysed intermolecular hydroacylation has only been achieved with tethered aldehydes. Currently, there is only limited control of branched to linear selectivity with alkyne substrates. Hydroacylation would be exceptionally useful in synthetic chemistry if the reaction conditions (i.e. catalyst) could be adapted so that the reaction was highly selective, could be used on an industrial scale (mild conditions, low catalyst loading and minimal waste) and has the flexibility to use many different substrates and aldehydes to form a wide range of organic products. In attempts to achieve these goals, or at least contribute towards them, I will modify the catalyst itself by changing the ligands on the catalyst as well as investigating the mechanism by which the selectivity is introduced. This will involve synthesising new ligands altogether, most likely to be diphosphine ligands, or applying known ligands but in previously unexplored catalytic systems. The logic behind this is to encourage C-H oxidative addition (which has been shown to be the rate limiting step) whilst also influencing the selectivity by applying steric and potentially electronic effects to the rhodium metal centre so to manipulate the binding site in a specific fashion. These new catalysts will also be designed in consideration of decarbonylation pathways that have been shown to kill the catalyst in intermolecular hydroacylation through the formation of stable rhodium-carbonyl complexes. This project falls within the EPSRC Physical Sciences research area. The fundamental synthetic chemistry research within this project will contribute towards the extensive research already conducted via investment from EPSRC research grants. This project is a combination of synthetic organic chemistry (the current EPSRC investment is £27.1 million), catalysis (£38.3 million) and synthetic coordination chemistry (£14.1 million) and is why I am co-supervised by some of the most prestigious and dynamic researchers in these disciplines of chemistry at the University of Oxford. The progress within this project will be both innovative and contribute towards the forefront of synthetic chemistry. Other than collaborating between the Weller Group and Willis Group there are currently no companies or collaborators in this project. However, if there is suitable interest from industrial backers then that will be encouraged.

本课题主要研究铑催化加氢酰化反应中的催化剂和催化循环。该项目位于有机化学和无机化学之间的边界，并由两者平等地提供适当的资金。在加氢酰化过程中，醛化合物上的羰基C-H键通过氧化加成到催化金属中心上而断裂，并与烯烃或炔烃底物形成新的C-C键。这对合成化学家来说特别有趣，因为该反应本质上是原子有效的，并且是形成C-C键的有用途径。有许多过渡金属催化的加氢酰化的例子，但铑催化是目前最多产的。铑催化的分子间加氢酰化反应仅用栓系醛实现。目前，只有有限的控制支链直链选择性与炔底物。如果反应条件（即催化剂）可以被调整以使得反应是高度选择性的，可以在工业规模上使用（温和条件、低催化剂负载和最小浪费）并且具有使用许多不同底物和醛以形成宽范围的有机产物的灵活性，则加氢酰化将在合成化学中特别有用。为了实现这些目标，或者至少有助于实现这些目标，我将通过改变催化剂上的配体以及研究引入选择性的机制来修改催化剂本身。这将涉及合成新的配体，最有可能是二膦配体，或应用已知的配体，但在以前未开发的催化体系。这背后的逻辑是促进C-H氧化加成（其已被证明是速率限制步骤），同时还通过对铑金属中心施加空间和潜在的电子效应来影响选择性，从而以特定的方式操纵结合位点。这些新的催化剂也将被设计在考虑脱羰基途径，已被证明杀死分子间加氢酰化催化剂通过形成稳定的铑-羰基络合物。该项目属于EPSRC物理科学研究领域的福尔斯。该项目中的基础合成化学研究将有助于通过EPSRC研究赠款的投资进行的广泛研究。该项目是合成有机化学（目前EPSRC投资为2710万英镑），催化（3830万英镑）和合成配位化学（1410万英镑）的组合，这就是为什么我由牛津大学化学学科中一些最负盛名和最具活力的研究人员共同监督。该项目的进展将是创新的，并有助于走向合成化学的前沿。除了Weller Group和Willis Group之间的合作外，目前没有公司或合作者参与该项目。然而，如果工业支持者有适当的兴趣，那么这将受到鼓励。