Design, Synthesis and Evaluation of Radical-Based Catalysts for the Direct Anti-M

直接抗M自由基催化剂的设计、合成和评价

• 批准号: 8690918
• 负责人: Jeffrey Scott Cannon
• 金额: $ 0.97万
• 依托单位: CALIFORNIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-02 至 2014-08-15
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8690918
• 关键词: Address; Alcohols; Alkenes; Boron; Carbon; Carbon Monoxide; Catalysis; Chemical Industry; Chemicals; Complex; Development; Environment; Evaluation; Future; Generations; Health; Human; Hydration status; Hydrogen; Hydrogen Bonding; Hydrolysis; Investigation; Learning; Lubricants; Manganese; Metals; Methods; Natural regeneration; Nature; Oxidants; Oxidation-Reduction; Oxygen; Peroxides; Pharmacologic Substance; Polymers; Population; Procedures; Process; Production; Quality of life; Reaction; Reagent; Recycling; Reducing Agents; Solutions; Stream; System; Testing; Transition Elements; Water; base; catalyst; chemical reduction; design; direct application; functional group; large scale production; oxidation; pi bond; pressure; small molecule; surfactant; wasting

DESCRIPTION (provided by applicant): Primary alcohols are important molecules in both the commodity and pharmaceutical chemical industries. Currently, their large-scale production involves the use of either high pressures of toxic and hazardous carbon monoxide and hydrogen gasses, or stoichiometric metal and peroxide reagents. A new method for their direct, catalytic synthesis by anti-Markovnikov hydration from readily available olefin precursors would be beneficial for the synthesis of bioactive small molecules, as well as polymers and commodity chemicals that benefit human health and quality of life. Current solutions to this problem either require multistep procedures, stoichiometric amounts of oxidant and/or reductant, or are limited in scope. A general approach to anti- Markovnikov hydration is proposed to proceed through radical addition to olefins, which provide the more highly substituted radical intermediate. A new catalytic cycle is developed where hydrogen atom transfer from a metal-hydroxo species generates the new carbon-hydrogen bond and propagates the radical reaction be regenerating the metal-oxo catalyst. This cycle involves two organometallic species of interchanging oxidation states, allowing reaction to proceed without the need for exogenous oxidants or reductants. This dual-mode catalysis will be facilitated by the design of dinuclear organometallic frameworks where the metal-oxo and the metal-hydroxo components are present in close proximity. This approach allows for hydrogen atom transfer to be accelerated by nature of it being an intramolecular process, and creates formal symmetry in the dinuclear redox transfer. Manganese oxo complexes have been identified as the ideal starting point for this investigation due to their known radical-type reactivity in both oxygen atom transfer and hydrogen atom transfer reactions. Olefin hydration catalysts developed from this proposal are anticipated to have general scope due to the typically high functional-group tolerance of radical reactions, allowing a wide range of alcohols to be synthesized from readily available olefin feedstocks.

描述（由申请人提供）： 伯醇是商品和药物化学工业中的重要分子。目前，其大规模生产涉及使用高压有毒有害的一氧化碳和氢气，或化学计量的金属和过氧化物试剂。通过从容易获得的烯烃前体中进行反马可夫尼科夫水合来直接催化合成它们的新方法将有利于生物活性小分子以及有利于人类健康和生活质量的聚合物和商品化学品的合成。目前对该问题的解决方案要么需要多步骤程序、化学计量量的氧化剂和/或还原剂，要么在范围上受到限制。提出了一种反马可夫尼科夫水合的通用方法，通过自由基加成到烯烃上进行，这提供了更高取代的自由基中间体。开发了一种新的催化循环，其中氢原子从金属-羟基物质转移产生新的碳-氢键并传播自由基反应以再生金属-氧催化剂。该循环涉及两种氧化态互换的有机金属，使反应无需外源氧化剂或还原剂即可进行。这种双模式催化将通过双核有机金属骨架的设计来促进，其中金属-氧和金属-羟基组分非常接近。这种方法允许氢原子转移因其分子内过程的性质而加速，并在双核氧化还原转移中产生形式对称性。由于锰氧配合物在氧原子转移和氢原子转移反应中具有已知的自由基型反应活性，因此已被确定为这项研究的理想起点。由于自由基反应通常具有高官能团耐受性，因此根据该提案开发的烯烃水合催化剂预计将具有广泛的应用范围，从而允许从容易获得的烯烃原料合成各种醇。