Mechanistic studies relevant to gold pi-activation catalysis

通过这一奖项，化学系的化学催化计划资助杜克大学化学系的Ross Wdenhoefer教授对基于元素金的催化反应进行基础研究，这种元素能够有效地将简单的有机分子转化为更复杂的有机分子。高效和选择性地将有机化合物转化为更高价值产品的新催化方法有可能改变各种类型的化学生产。在这个项目中，正在仔细研究金催化反应中涉及的特定反应步骤的机制，以使它们在化学转化中得到最佳应用。拟议的研究活动正在纳入对研究生和本科生研究人员的科学教育和培训，包括来自传统上在科学界代表性较低的群体的学生。研究生参加杜克大学研究生院提供的教育活动。研究生和本科生也在进行社区推广活动，并发展与催化和配位化学相关的演示。Widehoefer教授正在研究金(I)pi活化催化的机理，包括碳-碳多键的氢功能化以及烯炔和相关底物的环加成反应。尽管这一领域的工作越来越多，但关于金(I)催化的碳-碳多键的氢官能化机理的实验信息有限，同样，与金催化的烯炔环加成反应密切相关的阳离子金卡宾配合物和阳离子中间体的结构和反应活性的直接实验信息也很少。目前正在开展研究活动，以填补这些空白，并以实验为基础理解金的活化催化机理。本研究涉及四个方面的研究内容：(1)金催化碳-碳双键与强亲核体和弱给核体分子间氢功能化的机理；(2)金卡宾配合物中金-碳电子给予和d-pi回键的程度；(3)缺乏杂原子稳定的阳离子金环丙基卡宾配合物的结构和反应活性；(4)金催化的双环-[3.2.0]-庚烯的氢芳基化和骨架反应机理。实现这一建议中概述的活动有望以一种有意义的方式有助于理解金(I)催化的氢官能化机理以及金卡宾配合物的结构和反应活性。

With this award, the Chemical Catalysis Program of the Division of Chemistry is funding Professor Ross Widenhoefer in the Department of Chemistry at Duke University for fundamental studies of catalytic reactions based upon the element, gold, that enable the efficient transformation of simple organic molecules into more complex ones. New catalytic methods that efficiently and selectively transform organic compounds into higher value products have the potential to transform various classes of chemical production. Within this project, the mechanisms of specific reaction steps involved in gold-catalyzed reactions are being carefully investigated for their optimal application in chemical transformations. The proposed research activities are being integrated into the scientific education and training of the graduate and undergraduate student researchers, including students from groups traditionally underrepresented in the sciences. Graduate students are participating in educational activities offered through the Duke University Graduate School. Graduate students and undergraduate students are also performing community outreach activities and developing demonstrations related to catalysis and coordination chemistry.Professor Widenhoefer is investigating the mechanisms of gold(I) pi-activation catalysis, including the hydrofunctionalization of carbon-carbon multiple bonds and the cycloaddition of enynes and related substrates. Despite a growing body of work in this area, limited experimental information is available regarding the mechanisms of the gold(I)-catalyzed hydrofunctionalization of carbon-carbon multiple bonds and, likewise, little direct experimental information is available regarding the structure and reactivity of cationic gold carbene complexes and cationic intermediates germane to gold-catalyzed enyne cycloaddition. Research activities are being pursued to fill these gaps and to develop an experimentally-grounded understanding of the mechanisms of gold pi-activation catalysis. The research is addressing four areas of inquiry: (1) the mechanisms of gold-catalyzed intermolecular hydrofunctionalization of carbon-carbon double bonds with strong and weak donor nucleophiles, (2) the extent of gold-carbon electron donation and d-to-pi backbonding in gold carbene complexes, (3) the structure and reactivity of cationic gold cyclopropyl carbene complexes lacking heteroatom stabilization, and (4) the mechanisms of silver-catalyzed hydroarylation and skeletal rearrangement of bicyclo-[3.2.0]-heptenes formed in gold-catalyzed enyne cycloaddition. Realization of the activities outlined in this proposal is expected to contribute in a meaningful way to the understanding of the mechanisms of gold(I)-catalyzed hydrofunctionalization and the structure and reactivity of gold carbene complexes.