Synthesis via Decarboxylative Activation

化学系的化学合成计划支持Tunge教授的项目。Tunge教授是堪萨斯大学化学系的教员。 他正在开发新的反应类别，这些反应对环境的危害比目前最先进的技术要小。 为了做到这一点，Tunge教授和他的团队利用了羧酸固有的化学势。这些基团非常常见，可以在各种各样的现成的可再生材料中找到。通过开发利用羧酸的方法，Tunge集团能够将这些容易获得的材料转化为更有价值的化学品。这是通过两种类型的化学试剂的新组合来实现的，这反过来又降低了以前无法实现的反应的能量势垒。这导致了新类型的化学反应。在正在进行的具体项目中，羧酸被从分子中剥离出来，形成一种高度反应性的中间体，然后可以用来产生新的化学键。除了其科学价值外，这种实现合成目标的环保试剂组合还为培训学生在各个行业制造化学品和材料提供了绝佳的工具。 Tunge教授的小组还从事催化教育的科学推广，并正在开发新的途径，招募代表性不足的群体进入化学专业。 羧酸是有机反应物的普遍存在的、通常可再生的来源。 过去的化学反应允许Tunge基团通过脱羧作用将羧酸转化为各种化学物质，形成反应性亲核试剂（pKa 10-32）。在该项目中，羧酸与过渡金属催化剂结合，与光氧化还原催化剂结合，形成高碱度（pKa 32-48）的反应性亲核试剂，从而避免了对化学计量的有机金属试剂的需要。除了使用羧酸作为碳负离子等价物之外，正在开发新的策略，允许使用脱羧来产生自由基和碳阳离子中间体。 最终，这些研究被用来确定产生特定活性中间体的最佳条件，然后通过C-C键形成，消除和亲核捕获反应利用这些中间体。这种化学将催化与绿色化学和合成的主题结合起来。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The Chemical Synthesis Program of the Chemistry Division supports the project by Professor Tunge. Professor Tunge is a faculty member in the Department of Chemistry at The University of Kansas. He is developing new classes of reactions that are less harmful to the environment than current state-of-the-art technologies. To do this, Professor Tunge and his group harness the chemical potential inherent in carboxylic acids. These groups are very common and can be found in a wide variety of readily available, renewable materials. By developing methods that take advantage of carboxylic acids, the Tunge group is able to convert these readily available materials into more valuable chemicals. This is accomplished by the novel combination of two types of chemical reagents that in turn lowers the energy barrier to reactions that were previously unavailable. This leads to new types of chemical reactivity. In the specific project being pursued the carboxylic acid is stripped out of the molecule to form a highly reactive intermediate that can then be used to generate new chemical bonds. In addition to its scientific value, this combination of environmentally friendly reagents to achieve synthetic goals provides an excellent vehicle for training students to make chemicals and materials in a wide variety of industries. Professor Tunge's group is also engaged in scientific outreach in catalysis education and is developing new avenues for recruitment of underrepresented groups into the chemistry profession. Carboxylic acids are a ubiquitous, often renewable source of organic reactants. Past chemistries have allowed the Tunge group to transform carboxylic acids into a variety of chemicals using decarboxylation to form reactive nucleophiles (pKa 10-32). In this project, carboxylic acids are being combined with transition metal catalysts in combination with photoredox catalysts to form reactive nucleophiles of high basicity (pKa 32-48), thus obviating the need for stoichiometric organometallic reagents. In addition to using carboxylic acids as carbanion equivalents, new strategies are being developed that allow decarboxylation to be used to generate radical and carbocation intermediates. Ultimately, these studies are being employed to determine optimal conditions for generating specific reactive intermediates and then exploiting those intermediates through C-C bond forming, elimination, and nucleophilic trapping reactions. This chemistry integrates the themes of catalysis with green chemistry and synthesis. These themes are further emphasized in educational materials related to catalysis that are broadly disseminated online.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.