SusChEM: Copper Catalyzed C-H Functionalization

NSF化学催化计划支持乔治城大学的Timothy H.Warren教授为碳-氮(C-N)、碳-氧(C-O)和碳-碳(C-C)键的形成设计和开发新的方案。这项研究是通过详细了解关键的碳-氢(C-H)活化和C-官能团(C-FG)键形成反应来激励新的催化剂结构以实现可调选择性而推动的。该团队开发了与未活化胺的C-H胺化反应、与醇和受保护的酚的C-H醚化反应、与硝基烷烃的C-H硝基烷基化反应、与酮的C-H烷基化反应以及通过其他H-FG底物的C-FG形成反应。他们综合和机械地研究了关键的铜(II)-FG中间体，以了解它们在C-FG键形成和H原子提取反应中的作用。这些化学家研究了新的配体变化，以延长特别活性的铜(II)-FG中间体的寿命，并指导C-FG键的形成步骤。在可持续的化学合成中，广泛的具有合成价值的、与机械相关的C-H官能化反应解决了重要的挑战，例如利用氨将碳氢化合物转化为胺。这项研究属于“SusChEM”倡议，因为它促进了非贵金属催化剂-铜-的使用，而不是更稀有和更昂贵的替代品。通过与默克公司的合作，乔治敦大学的学生可以访问位于新泽西州拉赫韦的默克催化和自动化实验室。在默克实验室，学生们使用高通量方法来发现新的C-H官能化催化剂和催化转化。与德国埃尔兰根大学的Karsten Meyer教授和德克萨斯大学北部的Tom Cundari教授的持续合作分别使深入的光谱研究和计算洞察力成为可能。通过“更高的成就”组织，沃伦教授与来自资源匮乏社区低收入家庭的高危中学生建立联系，每年夏天在乔治敦举办的化学展(90-100名学生)中为他们的中学学者提供有趣的科学编程，并在每个学年DC公立学校关闭时至少对乔治敦进行一次较小规模的访问(10-20名学生)。NSF化学催化计划支持乔治敦大学的蒂莫西·H·沃伦教授设计和开发新的碳-氮(C-N)、碳-氧(C-O)协议。碳-碳(C-C)键的形成。这项工作涉及有价值的和可持续的化学合成，例如利用氨将碳氢化合物转化为胺。开发与碳形成键的新方法，消除对特定底物和保护/解除保护步骤的需要，可以加速有机化学合成，提高工业生产能力--所有这些都可以减少环境足迹，增强化学合成的可持续性。虽然许多碳-氢功能化系统使用钯和其他贵金属，但这种方法使用的是铜--一种低成本和毒性的地球上丰富的金属。行业合作使研究生能够探索高通量的发现方法，同时增加他们自己的就业市场。美国和德国正在进行的合作也为学生提供了在全球社区进行研究的更广阔的视角，提高了他们的技术和团队合作技能。沃伦教授和他的团队与来自资源匮乏社区的低收入家庭的高危中学生建立了联系，他们每年夏天都会通过一场化学表演，以及在哥伦比亚特区公立学校停课时偶尔对乔治敦大学进行较小规模的访问时，提供科学编程。

The NSF Chemical Catalysis Program supports the efforts of Professor Timothy H. Warren of Georgetown University in the design and development of new protocols for carbon-nitrogen (C-N), carbon-oxygen (C-O), and carbon-carbon (C-C) bond formation. This research is propelled by a detailed understanding of the key carbon-hydrogen (C-H) activation and C-functional group (C-FG) bond forming reactions to motivate new catalyst architectures for tunable selectivity. The team develops C-H amination reactions with unactivated amines, C-H etherification with alcohols and protected phenols, C-H nitroalkylation with nitroalkanes, and C-H alkylation with ketones as well as C-FG forming reactions via other H-FG substrates. They synthetically and mechanistically examine key copper(II)-FG intermediates to understand their roles in C-FG bond formation and H-atom abstraction reactions. These chemists examine new ligand variations to enhance the lifetime of particularly reactive copper(II)-FG intermediates as well as to direct the C-FG bond forming step. A wide range of synthetically valuable, mechanistically related C-H functionalization reactions address important challenges in sustainable chemical synthesis, such as the conversion of hydrocarbons to amines using ammonia. This research falls under the "SusChEM" initiative as it promotes the use of non-precious metal catalysts - copper - over more rare and expensive alternatives. Collaboration with Merck allows Georgetown students to access the Merck Catalysis and Automation Laboratory in Rahway, NJ. At the Merck laboratories, the students employ high throughput approaches to the discovery of new C-H functionalization catalysts and catalytic transformations. Ongoing collaborations with Prof. Karsten Meyer (U. Erlangen, Germany) and with Prof. Tom Cundari (U. North Texas) enable in depth spectroscopic studies and computational insights, respectively. Through the organization "Higher Achievement", Professor Warren connects with high-risk middle school students from low income families in under-resourced communities, providing fun science programming to their middle school scholars in a Chemistry Show (90-100 students) held at Georgetown each summer as well as at least one smaller visit (10-20 students) to Georgetown during each academic year when DC public schools are closed.The NSF Chemical Catalysis Program supports the efforts of Professor Timothy H. Warren of Georgetown University in the design and development of new protocols for carbon-nitrogen (C-N), carbon-oxygen (C-O), and carbon-carbon (C-C) bond formation. This work addresses valuable and sustainable chemical synthesis, such as the conversion of hydrocarbons to amines using ammonia. The development of new methodologies for bond formation with carbon that eliminate the need for specific substrates and protection / deprotection steps can accelerate organic chemical synthesis as well as enhance industrial throughput - all while reducing the environmental footprint and enhancing the sustainability of chemical synthesis. While many C-H functionalization systems employ palladium and other noble metals, this approach employs copper - an Earth-abundant metal of low cost and toxicity. Industrial collaborations allow graduate students to explore high throughput approaches to discovery while increasing their own job marketability. Ongoing collaborations within the U.S. and in Germany also provide students with the broader perspective of performing research in a global community, enhancing both their technical and teamwork skills. Professor Warren and his group connect with high-risk middle school students from low income families in under-resourced communities, providing science programming via a Chemistry Show each summer as well as during occasional smaller visits to Georgetown Univeristy held when District of Columbia public schools are closed.