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LeGrande M.俄克拉荷马州州立大学的斯劳特，其研究旨在利用金属与手性配体上的芳族基团的非经典相互作用来实现对映选择性催化。 这些不太了解的次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，可能导致用常规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联萘配体来创建手性无环二氨基卡宾和次膦酸酯配体，这些配体被优化以支持金属-芳烃相互作用。 这些相互作用的能力，以促进合成有用的对映选择性反应，包括碳-碳多重键，不对称的碳-碳耦合，和电环化的氢官能化，将进行研究。 结构，光谱和计算研究将探测弱金属-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合成手性、医学上重要的复杂分子的新催化方法是这项研究的预期成果。合成对映体纯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”对人体可能具有非常不同的影响。 这项研究可以提供新的工具来制备复杂的分子作为纯的单一对映异构体，可能以新的手性药物前体的形式为社会提供显着的好处。 这些研究将与一个名为“催化剂的魔力”的推广计划密切相关，该计划将使用动手实验向中学生介绍以催化为重点的研究和科学概念。 将在公共教育方面的既定合作者的帮助下，以美洲原住民学生比例高的学校为目标，目标是扩大美洲原住民对可能导致获得高等教育和科学职业的活动的参与。 金属-芳烃相互作用作为实现对映选择性催化的新主题的发展可能会对有用分子的合成技术产生变革性影响，通过刺激进一步研究过渡金属催化中次级相互作用的作用。

The Chemical Catalysis Program in the Chemistry Division at the National Science Foundation supports Professor LeGrande M. Slaughter of Oklahoma State University, 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.