Harnessing Nonclassical Metal-Arene Interactions to Achieve Enantioselective Catalysis

美国国家科学基金会化学部的化学催化项目支持北德克萨斯大学的LeGrande M. Slaughter教授，他的研究旨在利用金属与手性配体上芳香基团的非经典相互作用来实现对映选择性催化。这些鲜为人知的二级相互作用可以增强通常用于手性催化剂设计的空间相互作用，潜在地导致传统手性配体无法实现的高度对映选择性反应。该研究将使用一组新的手性双萘合子来创建手性无环二胺和亚磷酸酯配体，这些配体经过优化以支持金属-芳烃相互作用。这些相互作用促进合成有用的对映选择反应的能力，包括碳-碳多键的氢化官能化，不对称碳-碳偶联和电环化，将被研究。结构、光谱和计算研究将探讨弱金属-芳烃相互作用的性质及其在催化中的作用，重点是催化重要金属钯和金。从廉价的非手性前体中合成手性的、具有重要医学意义的复杂分子的新催化方法是本研究的预期结果。合成纯对映体形式的手性分子的能力很重要，因为药物分子的两种对映体或“镜像”对人体的影响可能非常不同。这项研究可以提供新的工具来制备复杂分子作为纯单一对映体，潜在地以新的手性药物前体的形式为社会提供重大的利益。这些研究将与一个名为“催化剂的魔力”的推广项目密切相关，该项目将通过动手实验向中学生介绍以催化为重点的研究和科学概念。在公共教育领域已建立的合作伙伴的帮助下，将以美洲土著学生比例高的学校为目标，目的是扩大美洲土著参与可能导致获得高等教育和科学职业的活动。金属-芳烃相互作用的发展作为实现对映选择性催化的新基序，可以通过刺激对过渡金属催化中很少被研究的二级相互作用的进一步研究，对有用分子的合成技术产生革命性的影响。

The Chemical Catalysis Program in the Chemistry Division at the National Science Foundation supports Professor LeGrande M. Slaughter of the University of North Texas, for studies aimed at utilizing nonclassical interactions of metals with aromatic groups on chiral ligands to achieve enantioselective catalysis. These poorly-understood secondary interactions could augment the steric interactions typically employed in chiral catalyst design, potentially leading to highly enantioselective reactions that are not achievable with conventional chiral ligands. The research will use a set of new chiral binaphthyl synthons to create chiral acyclic diaminocarbene and phosphinite ligands that are optimized to support metal-arene interactions. The ability of these interactions to promote synthetically useful enantioselective reactions, including hydrofunctionalizations of carbon-carbon multiple bonds, asymmetric carbon-carbon couplings, and electrocyclizations, will be investigated. Structural, spectroscopic, and computational studies will probe the nature of weak metal-arene interactions and their role in catalysis, focusing on the catalytically important metals palladium and gold. New catalytic methods for the synthesis of chiral, medicinally important complex molecules from inexpensive achiral precursors are an expected outcome of this research. The ability to synthesize chiral molecules in enantiomerically pure form is important, because the two enantiomers or 'mirror images' of a drug molecule can have very different effects on the human body. This research could provide new tools to prepare complex molecules as pure single enantiomers, potentially providing significant benefits to society in the form of new chiral drug precursors. These studies will be closely tied to an outreach program entitled 'The Magic of Catalysts' that will use hands-on experimentation to introduce middle school students to concepts of research and science using catalysis as a focus. Schools with high percentages of Native American students will be targeted with the help of established collaborators in public education, with a goal of broadening participation of Native Americans in activities that could lead to attainment of higher education and careers in science. The development of metal-arene interactions as a novel motif for achieving enantioselective catalysis could have a transformative impact on technologies for the synthesis of useful molecules by stimulating further study of the little-investigated role of secondary interactions in transition metal catalysis.