Bespoke Bimetallics for Chemical Cooperativity

英国化学和制药部门的重要性可以从统计数据中看出，它每个工作日为我们的国内生产总值（一年中提供的商品和服务的总价值）提供6000万英镑的附加值（相当于每年150亿英镑）。尖端的研究，创新和可持续性是这个项目的核心。该研究是在有机金属化学，化学的核心领域，是在无数的真实的世界应用中使用，跨越化学和其他学科，如生物化学和材料科学。包含有机部分和金属部分的有机金属化合物是构建大小分子的基本工具。大部分已知的化学方法依赖于作为贵过渡金属的有机金属化合物的金属部分（通常为钯、铂、铑、铱、钌和锇），这对于从农用化学品到药品的许多特种化学品的制造至关重要（尤其是抗癌药物）。（非贵）金属一般要便宜得多（由于其较高的天然丰度）并且反映出地壳中的这种高丰度，它们比其贵金属对应物具有更少的毒性问题。问题是它们的化学性质（它们有效进行有用反应的能力）相比之下相当有限，因此它们在许多化学过程中往往效率低下。如果贱金属化学能够发展到贵过渡金属化学的地位，或者更好地超越这种地位，那么可持续性将得到显著改善，对环境不太友好的贵过渡金属的依赖将减少。研究小组最近的进展表明，通过制备含有两种贱金属的有机金属化合物，元素，而不是一个。所有这些金属对共有的金属是碱金属（锂、钠或钾），而第二种金属是镁、锌、铝或地球上丰富的过渡金属铁和锰。通过形成在单金属系统中不可能的混合金属双金属结构，诱导了协同效应，其改变了贱金属的反应性，从而开启了大量目前贱金属自身无法实现的新颖反应。协同性在我们通过碱金属-Fe或-Mn伙伴关系的目标C-C键形成和C-F键活化中将是特别重要的，因为目前这些反应通常是贵过渡金属催化的领域。实现这种可持续基础金属化学的升级本身将是一个重大突破，但该项目将面临额外的雄心勃勃的挑战。碱金属有机金属化学总是需要在厌氧条件下进行，因为所涉及的化合物即使在痕量的空气或水分下也会迅速分解。然而，该团队最近取得了非凡的发现，某些有机碱金属反应可以在有氧条件下通过使用深铕溶剂（DES）而不是工业标准的经典有机溶剂进行。DES比有机溶剂更具成本效益，更环保，更具有生物可再生性，改用它们也将消除对昂贵的惰性气氛协议的需求。DES的概念验证结果已经与单一的基础金属，所以挑战是在DES中开发这种新的化学物质。成功将影响全球有机金属化学的实践。

The importance of the UK's chemical and pharmaceutical sector can be seen in the statistic that it supplies £60M of added value each working day (that equates to £15bn a year) to our Gross Domestic Product (the total value of goods and services provided by a country in one year). Cutting edge research, innovation and sustainability lie at the heart of this project. The research is in organometallic chemistry, a core area of chemistry that is utilised in a myriad of real world applications, spanning chemistry and other disciplines such as biochemistry and material science. Organometallic compounds, comprising an organic moiety and a metal moiety are essential tools for constructing molecules big and small. A large proportion of known chemical processes depend on the metal moiety of organometallic compounds being a precious transition metal (commonly palladium, platinum, rhodium, iridium, ruthenium, and osmium), which are essential for the manufacture of numerous specialty chemicals from agrochemicals through to pharmaceuticals (especially anticancer drugs).Base (non-precious) metals are generally much cheaper (due to their higher natural abundance) and reflecting this high abundance in the earth's crust they have less toxicity concerns than their precious metal counterparts. The problem is their chemistry (their ability to carry out useful reactions efficiently) is rather limited by comparison so more often than not they are inefficient in many chemical processes. If base metal chemistry could be developed to the status of precious transition metal chemistry or better still to go beyond this status, then sustainability would be significantly improved and reliance on less environmentally benign precious transition metals would be reduced.Recent advances by the research team have demonstrated that base chemistry can be made orders of magnitude more efficient by preparing organometallic compounds that contain two base metal elements instead of one. The metal common to all of these metal pairs is an alkali metal (lithium, sodium or potassium), while the second metal is magnesium, zinc, aluminium or the earth-abundant transition metals iron and manganese. By forming mixed-metal bimetallic structures impossible in single-metal systems, cooperative effects are induced which transform the reactivity of the base metals opening up a vast number of novel reactions that are currently inaccessible to base metals on their own. Cooperativity will be especially important in our targeted C-C bond formations and C-F bond activations through alkali metal -Fe or -Mn partnerships as currently these reactions are generally the domain of precious transition metal catalysis. Realising this escalation of sustainable base metal chemistry will be a major breakthrough in itself but this project will take on an additional ambitious challenge. Alkali metal organometallic chemistry invariably needs to be performed under anaerobic conditions as the compounds involved rapidly decompose with even traces of air or moisture. However, the team recently made the extraordinary finding that certain organoalkali metal reactions could be run under aerobic conditions by using Deep Eutectic Solvents (DES) as opposed to industry standard classical organic solvents. DES are more cost-effective, greener and biorenewable than organic solvents and switching to them would also do away with the need for costly inert atmosphere protocols. The proof of concept results with DES have been with single base metals, so the challenge is to develop this new bimetallic chemistry in DES. Success will impact the practice of organometallic chemistry worldwide.