LEAPS-MPS: Heterogeneous Asymmetric Catalysis with Chiral Metal Clusters

LEAPS-MPS：手性金属簇的多相不对称催化

• 批准号: 2316991
• 负责人: ANINDITA DAS
• 金额: $ 24.99万
• 依托单位: Southern Methodist University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2316991&HistoricalAwards=false
• 关键词: LEAPS; MPS; Heterogeneous; Asymmetric; Catalysis

In this project managed by the Chemistry Division at NSF, Professor Anindita Das and her students at Southern Methodist University will perform studies that aim to transpose ligand-directed asymmetric catalysis from homogeneous to heterogeneous systems by installing new chiral ligands on the surfaces of metal clusters. Asymmetric catalytic reactions represent a powerful way to synthesize optically active compounds which have tremendous implications in medicine. For instance, more than 75% of the small-molecule drugs approved by the FDA in the last 5 years are chiral compounds. Over the years, chemists have achieved tremendous success in developing homogeneous asymmetric organocatalysts as well as transition-metal complex catalysts by rationally designing chiral ligands which mimic the active sites of enzymes. However, using this strategy for industrially relevant heterogeneous metal nanoparticle-based catalysts to achieve “predictive heterogeneous asymmetric catalysis” is a longstanding challenge owing to the inherent polydispersity of nanoparticles synthesized by conventional routes. To address this limitation, Professor Das and her students will develop atomically precise model metal clusters the surfaces of which will feature new chiral ligands to tune their catalytic activity, analogous to homogeneous asymmetric catalysts. Their studies could help identify the critical parameters related to asymmetric catalytic activity of metal cluster-based model catalysts leading to better heterogeneous catalyst design in future. This research is integrated with numerous outreach activities to engage and encourage underrepresented, first-generation, or low-income students to pursue STEM degrees and careers. These include organizing workshops and demo-experiments at nearby high schools and MSIs to promote public literacy about science and research. Additionally, trainings on hidden implicit biases and cultivating cultural intelligence will be undertaken to create an inclusive and supportive lab environment.Professor Das and her students will synthesize and characterize a series of atomically precise metal clusters protected by new chiral ligands. The synthetic mechanisms of these clusters will be investigated by various techniques such as single crystal X-ray crystallography, NMR, UV-visible and fluorescence spectroscopy, circular dichroism (CD) spectroscopy, electrochemical analysis, and mass spectrometry. These synthetic guidelines will then be applied to bimetallic chiral metal clusters to study the effects of cooperative interactions in model asymmetric transformations. Ultimately, the design rules generated from this research may be broadly applied to other classes of heterogeneous nanomaterials to understand and tailor their asymmetric catalytic properties with atomic precision.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.

在由NSF化学部管理的该项目中，南方卫理公会大学的Anindita Das教授和她的学生将进行研究，旨在通过将新的手性配体安装在金属金属簇的表面上，从而将以配体定向的不对称催化从同质到异质系统进行。不对称催化反应代表了合成光学活性化合物的强大方法，这些化合物在医学中具有巨大的影响。例如，在过去5年中，FDA批准的小分子药物中有75％以上是手性化合物。多年来，化学家通过合理设计模仿酶的活性位点的手性配体来发展均质不对称有机催化剂以及过渡金属复合物催化剂。然而，使用这种策略来实现基于工业相关的金属纳米粒子催化剂来实现“预测异质不对称催化”，这是一项长期的挑战，这是由于纳米粒子的继承多分散性，由常规路线合成。为了解决这一限制，DAS教授和她的学生将开发原子上精确的模型金属簇，其表面将具有新的手性配体，以调整其催化活性，类似于均质的不对称催化剂。他们的研究可以帮助确定与基于金属簇的模型催化剂的不对称催化活性相关的关键参数，从而在未来获得更好的异质催化剂设计。这项研究与无数外展活动融为一体，以参与并鼓励代表性不足，第一代或低收入学生购买茎学位和职业。其中包括在高中和MSI附近组织研讨会和演示体验，以促进有关科学和研究的公众素养。此外，还将进行有关隐藏隐性偏见和培养文化智能的培训，以创建一个包容性和支持性的实验室环境。DAS和她的学生将合成并表征一系列由新手性质配体保护的原子精确的金属簇。这些簇的合成机制将通过各种技术进行研究，例如单晶X射线晶体学，NMR，UV可见和荧光光谱，循环二色性（CD）光谱，电化学分析和质谱法。然后，这些合成指南将应用于​​双金属手性金属簇，以研究模型不对称转换中合作相互作用的影响。最终，这项研究产生的设计规则可能会广泛应用于其他类别的异构纳米材料，以理解和量身定制其不对称的催化性能，具有原子精度。该奖项反映了NSF的法定任务，并通过使用该基金会的知识分子功能和广泛的影响来评估NSF的法定任务，并被认为是诚实的支持。