CO2Chem - Redox-Neutral Photocatalytic CH Carboxylation of Hydrocarbons with CO2

CO2Chem - 碳氢化合物与 CO2 的氧化还原中性光催化 CH 羧化反应

• 批准号: 465006243
• 负责人: Professor Dr. Burkhard König
• 金额: --
• 依托单位: Institut für Organische Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/465006243?language=en
• 关键词: CO2Chem; Redox; Neutral; Photocatalytic; CH

Recent years have seen large efforts in mimicking biological photosynthesis by technical processes with the goal of converting solar energy into chemically stored energy. The energy-rich molecules produced in such processes are typically dihydrogen, methane or methanol from the reduction of carbon dioxide or syngas (H2/CO) as feed for the Fischer-Tropsch process. In contrast, the solar-driven synthesis of valuable chemicals using carbon dioxide is still at a very early stage of development. So far, carbon dioxide is only used to a small extent as a raw material in chemical synthesis, but industrial projects in polymer production have shown the feasibility and sustainability of the approach. This project aims to develop the synthetic and mechanistic basis for the photochemical, redox-neutral C-H carboxylation of saturated hydrocarbons with carbon dioxide. Our preliminary data clearly show that carbon dioxide is a valuable reagent in functionalizations of C-H bonds in which carbon dioxide is formally inserted into the carbon hydrogen bond. The redox neutral carboxylation of arenes, styrenes as well as benzylic or α-carbonyl C-H bonds was already realized. The developed methods are highly valuable and proved useful in the synthesis of drug molecules, such as ibuprofen, from simple arene precursors and carbon dioxide. It should be clearly stated, however, that both existing methods preclude the use of the most abundant, non-activated C(sp3)-H bonds. In order to address this challenge, we propose new synthetic strategies based on photocatalytically generated alkyl radicals and earth-abundant metal complexes to provide C-H carboxylation in an overall redox-neutral process. The combined experience of the applicants in cobalt-catalysis and photocatalysis will be used to establish methodologies for the conversion of non-activated aliphatic hydrocarbons into functionalized chemicals with carbon dioxide as a C1 synthon.

近年来，人们在通过技术过程模拟生物光合作用方面做出了巨大努力，其目标是将太阳能转化为化学储存的能量。这些过程中产生的富含能量的分子通常是二氧化碳或合成气 (H2/CO) 还原产生的氢气、甲烷或甲醇，作为费托过程的原料。相比之下，利用二氧化碳通过太阳能合成有价值的化学品仍处于非常早期的发展阶段。到目前为止，二氧化碳仅在化学合成中少量用作原料，但聚合物生产的工业项目已经证明了该方法的可行性和可持续性。该项目旨在开发饱和烃与二氧化碳的光化学、氧化还原中性 C-H 羧化反应的合成和机械基础。我们的初步数据清楚地表明，二氧化碳是 C-H 键功能化的一种有价值的试剂，其中二氧化碳被正式插入到碳氢键中。芳烃、苯乙烯以及苄基或α-羰基C-H键的氧化还原中性羧化已经实现。所开发的方法非常有价值，并被证明可用于从简单的芳烃前体和二氧化碳合成药物分子，例如布洛芬。然而，应该明确指出，两种现有方法都排除了使用最丰富的非活化 C(sp3)-H 键。为了应对这一挑战，我们提出了基于光催化产生的烷基自由基和地球丰富的金属配合物的新合成策略，以在整个氧化还原中性过程中提供 C-H 羧化。申请人在钴催化和光催化方面的综合经验将用于建立以二氧化碳作为C1合成子将非活化脂肪烃转化为功能化化学品的方法。