SusChEM: C-H Bond Electroactivation of Nonpolar Organic Substrates in Water: Enzyme-Mediated Reaction Pathways in Microemulsions

SusChEM：水中非极性有机底物的 C-H 键电活化：微乳液中酶介导的反应途径

• 批准号: 2035669
• 负责人: Jie He
• 金额: $ 46.49万
• 依托单位: University of Connecticut
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-11-01 至 2024-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2035669&HistoricalAwards=false
• 关键词: SusChEM; Bond; Electroactivation; Nonpolar; Organic

Running organic reactions in water rather than organic solvents increases sustainability by reducing the use of harmful solvents and lowering overall cost. Unfortunately, most nonpolar organic molecules do not dissolve in water. Most synthetic catalysts also work poorly in water, especially those aimed at producing specialty products such as pharmaceuticals. Alternatively, enzymes are excellent biocatalysts, even for reactions taking place in water. This project aims to combine synthetic copper polymer catalysts with inexpensive peroxidase enzymes to speed reactions of nonpolar organic molecules in water. Electrosynthesis will take place in microemulsions, which are mixtures of oil, water and low-toxicity, low-cost detergents, that feature nanoscale interfaces of oil and water. These emulsions improve the solubility and diffusion rate of nonpolar reactants by delivering reactants to water-rich enzyme sites for catalysis. The findings from this project will provide practical guidelines to next-generation sustainable synthesis of pharmaceutical and specialty chemicals. In addition to advanced training of graduate students, the project will offer training opportunities to undergraduate and high school students though summer research activities. Workshops on electrochemical enzyme catalysis for chemical synthesis will be organized through outreach activities for K-12 teachers and students. This proposal targets the development of high-temperature, sustainable bioelectrocatalytic materials and their applications to electrooxidation of C-H bonds by oxygen in water. New catalytic films will be fabricated via layer-by-layer self-assembly of synthetic Cu polymer catalysts and peroxidase-like enzymes. Such electrocatalytic systems will be capable of carrying out cooperative, cascade electrocatalysis of oxygen activation by Cu catalysts through 2e- reduction to produce hydrogen peroxide which further activates peroxidases to drive the oxidization of nonpolar organic substrates. The hybrid film of Cu catalysts and peroxidases will also be stabilized by chemical crosslinking to carry out high-temperature electrosynthesis ( 90 degrees C). Detailed kinetic studies will be analyzed in the hybrid films and the film composition will be fine-tuned to optimize the production rate of hydrogen peroxide on the Cu catalysts and its consumption rate by the peroxidases. The activity and selectivity of hybrid films will be investigated and optimized for two types of C-H activations in naphthyls (sp2 C-H) and alkylbenzenes (sp3 C-H) in various nanostructured microemulsions. True green chemistry systems in microemulsions that not only resolve the solubility issue of non-polar substrates but also provide well-defined conditions for enzymatic catalysts similar to aqueous solutions at neutral pH will be developed. Electrochemical kinetic and spectroscopic studies will be used to understand diffusion kinetics and reaction pathways, as well as the thermodynamic activation barriers for nonpolar reactants.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在水中而不是有机溶剂中进行有机反应可以减少有害溶剂的使用并降低总体成本，从而提高可持续性。不幸的是，大多数非极性有机分子不溶于水。大多数合成催化剂在水中也表现不佳，尤其是那些旨在生产药品等特种产品的催化剂。另外，酶也是极好的生物催化剂，即使对于在水中发生的反应也是如此。该项目旨在将合成铜聚合物催化剂与廉价的过氧化物酶相结合，以加速水中非极性有机分子的反应。电合成将在微乳液中进行，微乳液是油、水和低毒、低成本清洁剂的混合物，具有纳米级的油和水界面。这些乳液通过将反应物输送到富含水的酶位点进行催化，从而提高非极性反应物的溶解度和扩散速率。该项目的研究结果将为下一代药物和特种化学品的可持续合成提供实用指南。除了研究生的高级培训外，该项目还将通过暑期研究活动为本科生和高中生提供培训机会。将通过针对 K-12 教师和学生的外展活动组织关于化学合成的电化学酶催化的研讨会。该提案的目标是开发高温、可持续的生物电催化材料及其在水中氧对 C-H 键的电氧化中的应用。新的催化薄膜将通过合成铜聚合物催化剂和类过氧化物酶的逐层自组装来制造。这种电催化系统将能够通过铜催化剂通过2e-还原对氧活化进行协同级联电催化，产生过氧化氢，过氧化氢进一步激活过氧化物酶以驱动非极性有机底物的氧化。 Cu催化剂和过氧化物酶的混合膜也将通过化学交联来稳定，以进行高温电合成（90℃）。将在混合薄膜中分析详细的动力学研究，并对薄膜成分进行微调，以优化铜催化剂上过氧化氢的生成速率及其过氧化物酶的消耗速率。将针对各种纳米结构微乳液中萘基 (sp2 C-H) 和烷基苯 (sp3 C-H) 中两种类型的 C-H 活化，研究和优化杂化膜的活性和选择性。将开发真正的绿色微乳液化学系统，不仅解决非极性底物的溶解度问题，而且还为类似于中性 pH 值水溶液的酶催化剂提供明确的条件。电化学动力学和光谱研究将用于了解扩散动力学和反应途径，以及非极性反应物的热力学活化势垒。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响进行评估，被认为值得支持审查标准。

项目成果

Biocatalytic Nitration of Phenols in Microemulsions at Elevated Temperatures Using Enzymes Stabilized on Magnetic Beads

使用磁珠上稳定的酶在高温下生物催化硝化微乳液中的酚

• DOI: 10.1002/cctc.202300119
• 发表时间: 2023-06
• 期刊: ChemCatChem
• 影响因子: 4.5
• 作者: Kankanamage, Rumasha N. T.;Ahiadu, Ben K.;He, Jie;Rusling, James F.
• 通讯作者: Rusling, James F.

Electrochemical transformations catalyzed by cytochrome P450s and peroxidases

细胞色素 P450 和过氧化物酶催化的电化学转化

• DOI: 10.1039/d3cs00461a
• 发表时间: 2023-07
• 期刊: Chemical Society Reviews
• 影响因子: 46.2
• 作者: Kumar, Neeraj;He, Jie;Rusling, James F.
• 通讯作者: Rusling, James F.

Single-Atom Cobalt Catalysts Coupled with Peroxidase Biocatalysis for C–H Bond Oxidation

单原子钴催化剂与过氧化物酶生物催化结合用于 C–H 键氧化

• DOI: 10.1021/acsami.3c03053
• 发表时间: 2023-08
• 期刊: ACS Applied Materials & Interfaces
• 影响因子: 9.5
• 作者: Liaqat, Maham;Kankanamage, Rumasha Nipuni;Duan, Hanyi;Shimogawa, Ryuichi;Sun, Jiyu;Nielsen, Monia;Shaaban, Ehab;Zhu, Yuanyuan;Gao, Puxian;Rusling, James F.;et al
• 通讯作者: et al

Hydrophobic pockets built in polymer micelles enhance the reactivity of Cu 2+ ions

聚合物胶束中内置的疏水袋增强了 Cu 2 离子的反应性

• DOI: 10.1039/d3qm00110e
• 发表时间: 2023-05
• 期刊: Materials Chemistry Frontiers
• 影响因子: 7
• 作者: Wei, Zichao;Liu, Chung;Luo, Qiang;Thanneeru, Srinivas;Angeles;Nieh, Mu;He, Jie
• 通讯作者: He, Jie