Towards Absolute Asymmetric Synthesis

通过这一奖项，美国国家科学基金会化学部的化学合成计划支持了威斯康星大学麦迪逊分校化学系的特赫希克·尹教授的研究。尹教授对控制分子的形状很感兴趣。许多重要的有机分子，包括药物分子和基本的生物分子，如氨基酸和糖，可以左手或右手形式存在。这两种镜像形式以非常不同的方式与生物系统相互作用，因此在有机分子的合成中控制左旋手是至关重要的。尹教授带领一个由本科生和研究生组成的团队，研究光是否可以用来控制有机分子的左右手。为了做到这一点，他们创造了一系列催化剂，这些催化剂可以吸收光线，然后诱导分子转化，并对结果产品的形状进行出色的控制。这项工作采取了跨学科的方法，结合了化学科学的多个领域。此外，参与这个项目的Yoon实验室的学生正在通过制作一个新的播客来帮助向理科新手传播科学研究。这一季的播客第一季在各种免费播客平台上的下载量已超过2500次。本项目中的手性光催化剂是八面体Ir络合物，其配体以明确的螺旋手性排列在金属周围。这类化合物构成了这些研究的一个有吸引力的起点：它们具有强大的和研究得很好的光化学；它们是一系列有机转化的相当有效的光敏剂；它们可以很容易地以立体化学纯形式合成。从这些研究中得到的新设计的手性光敏剂是非常有效的不对称催化剂，多学科方法研究它们的反应揭示了丰富多样的机理。这些研究为不同群体的本科生和研究生提供了培训机会，这些领域是当代化学工业感兴趣的重要科学领域。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With this award, the Chemical Synthesis Program of the NSF Division of Chemistry is supporting research by Professor Tehshik Yoon of the University of Wisconsin–Madison’s Chemistry Department. Professor Yoon is interested in controlling the shape of molecules. Many important organic molecules, including drug molecules and elementary biomolecules such as amino acids and sugars can exist in either left- or right-handed forms. These two mirror-image forms interact with biological systems in very different ways, so it is critically important to control the handedness in the synthesis of organic molecules. Professor Yoon leads a team of undergraduate and graduate students to investigate if light can be used to control the handedness of organic molecules. To do so, they have created a family of catalysts that absorb light and then induce molecular transformations with excellent control over the shape of the resulting products. This work takes an interdisciplinary approach combining multiple areas of the chemical sciences. In addition, students in the Yoon laboratory working on this project are helping to disseminate scientific research to novice science students by producing a new podcast. The first season of this podcast has been downloaded over 2500 times through a variety of free podcasting platforms.The chiral photocatalysts in this project are octahedral iridium complexes whose ligands are arranged about the metal with well-defined helical chirality. This class of compounds constitutes an attractive starting point for these studies: they possess a robust and well-studied photochemistry; they are quite effective photosensitizers for a range of organic transformations; and they can easily be synthesized in stereochemically pure form. The newly designed chiral photosensitizers resulting from these studies are remarkably efficient asymmetric catalysts, and a multidisciplinary approach to studying their reactions reveals a rich variety of mechanisms. These studies offer a training opportunity for a diverse group of undergraduate and graduate students in scientific fields of significant contemporary interest to the chemical industries.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.