Mining the air for amines

开采空气中的胺

• 批准号: 2752688
• 金额: --
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2752688
• 关键词: Mining; air; amines

Dinitrogen is plentiful and the source of ammonia (used in fertilizers on mega-tonne scales) and organoamines (for speciality, fine, and pharmaceutical chemicals) via Haber Bosch industrial processes, but ironically it is one of the most challenging bonds to activate and thus incorporate into added-value molecules in a sustainable way. Fortunately, however, various transition metals are quite effective at binding and activating dinitrogen, so the challenge for us is to harness that and develop it to include functionalization. Producing ammonia is still fundamentally interesting from a mechanistic perspective, but a major step-change will be to activate dinitrogen and incorporate it directly into organic molecules containing NR3 and R2N-NR2 units, that have extensive added-value, thus by-passing the need for several post-ammonia reaction steps. Elucidating the mechanism of these transformations is also critical to achieve, because this thermodynamic and kinetic information at a fundamental level is badly needed to feedback into designing new dinitrogen to organoamine catalytic cycles.After decades of research, there are still only 7 metals from the entire Periodic Table that in molecular species can catalytically reduce and fix dinitrogen into ammonia and 5 were added in the past 4 years: Ti, V, Mo, Fe, Ru, Os, Co. Ti is our work introduced only recently (Scheme 1 left, Angew. Chem. Int. Ed., 2018, 57, 6314-6318), which is appealing as Ti is 9th in crustal abundance and 2nd only to Fe for metals that can activate dinitrogen. Now we have established that a molecular Ti-Tren complex can catalytically fix dinitrogen to ammonia, and also shown that FLPs can split dihydrogen and introduce those H-atoms to produce ammonia (Scheme 1 right, Angew. Chem. Int. Ed., 2019, 58, 6674-6677). We seek to develop this science.Our aim is to make major advances in our understanding of dinitrogen reduction chemistry and its fixation by way of functionalization into ammonia and organoamines directly. We seek to achieve this aim by securing the following objectives: extend this catalysis to Zr and Hf; develop this to include direct formation of NR3 and R2N-NR2 compounds via C-N bond formation reactions without having to go via ammonia; unravel the reaction mechanisms to feedback, via structure-reactivity correlations, to reaction optimisation and generation of new catalytic cycles; develop the FLP aspect to deliver catalytic ammonia synthesis using dihydrogen.This project will thus involve: significant synthetic studies; catalysis; mechanistic analysis; computational modelling.The project is firmly rooted in chemocatalysis. It seeks to exploit the inorganic and N2 reduction expertise of STL with the amine synthesis and mechanistic expertise of DW to derive new chemical reactivity and atom-efficient routes to amines which could have biological relevance. It is therefore by definition a problem-solving, inter-disciplinary integrated catalysis project that seeks to make transformative step-changes in our understanding of catalysis that links to real-world challenges involving ammonia and organoamine syntheses. At this point in time with two preliminary papers published, this project is very much as TRL0, but we believe this project will be the perfect vehicle to develop the science and links to industry, via iCAT andthe UK Catalysis Hub, in order to make the fundamental-applied transition and raise the TRL rating of this research to exploitable outcomes.

通过Haber Bosch工业流程，二氮是丰富的氨（用于百万吨规模的肥料）和有机胺（用于特种、精细和制药化学品）的来源，但具有讽刺意味的是，它是最具挑战性的键之一，难以激活，从而以可持续的方式将其纳入增值分子。然而，幸运的是，各种过渡金属在结合和激活二氮方面非常有效，所以我们面临的挑战是利用它并发展它包括功能化。从机制的角度来看，生产氨仍然是一个有趣的事情，但一个主要的步骤变化将是激活二氮，并将其直接纳入含有NR3和R2N-NR2单元的有机分子中，这些单元具有广泛的附加值，从而绕过了氨反应后几个步骤的需要。阐明这些转化的机制也是至关重要的，因为这些基本的热力学和动力学信息迫切需要反馈到设计新的二氮到有机胺的催化循环中。经过几十年的研究，整个元素周期表中能够在分子形态上催化还原和固定二氮为氨的金属仍然只有7种，其中5种是近4年才加入的：Ti， V, Mo, Fe, Ru, Os, Co. Ti是我们最近才介绍的工作（Scheme 1 left, Angew）。化学。Int。编者，2018,57,6314-6318)，这很有吸引力，因为钛在地壳丰度中排名第九，在可以激活二氮的金属中仅次于铁。现在我们已经确定了一个分子Ti-Tren配合物可以催化将二氮固定到氨上，并且还证明了FLPs可以分裂二氢并引入那些h原子来产生氨（方案1，对，Angew）。化学。Int。编辑，2019,58,6674-6677)。我们寻求发展这门科学。我们的目标是在我们对二氮还原化学及其通过直接功能化成氨和有机胺的固定方式的理解方面取得重大进展。我们力求通过确保以下目标来实现这一目标：将这种催化作用扩展到Zr和Hf；发展到包括通过C-N键形成反应直接生成NR3和R2N-NR2化合物，而不需要经过氨；揭示反应机制反馈，通过结构-反应性相关性，反应优化和产生新的催化循环；发展FLP方面，以提供使用二氢催化合成氨。因此，这个项目将涉及：重要的综合研究；催化;机械的分析;计算模型。这个项目牢牢扎根于化学催化。它寻求利用STL的无机和N2还原专业知识与DW的胺合成和机械专业知识，以获得新的化学反应性和原子效率途径，以获得可能具有生物相关性的胺。因此，从定义上讲，这是一个解决问题的跨学科综合催化项目，旨在改变我们对催化的理解，将其与涉及氨和有机胺合成的现实挑战联系起来。在这个时间点上，有两篇初步论文发表，这个项目非常接近TRL0，但我们相信这个项目将是一个完美的工具，通过iCAT和英国催化中心，发展科学和与工业的联系，以实现基础应用的过渡，并将本研究的TRL评级提高到可开发的结果。