Mechanistic and Catalytic Studies of Reversible Covalent Bonding

在美国国家科学基金会化学结构、动力学和机理计划的支持下，德克萨斯大学奥斯汀分校的埃里克·安斯林教授将领导一项专注于动态共价键的研究计划。目前有四个现代化学领域正在利用动态共价键：超分子化学、动态组合化学(DCC)、有机催化和酶抑制。然而，在这些地区常规利用的动态反应是有限的。这是因为大多数涉及可逆共价键的反应很慢才能达到平衡，因此在时间尺度上交换成分是不切实际的。我们的目标是扩大实用的可逆系统的数量。为此，Anslyn团队将首先探索四个可逆共价反应的机制，利用他们小组最近在这方面取得的成功，最后设计出加速可逆共价交换的催化方法。他们将针对的四个可逆反应是：硫醇共轭加成、缩醛形成、半氨基醚形成和亚磷酸酯交换。了解这四个反应的机理并揭示它们的催化方法将对化学界产生广泛的影响，原因有两个。首先，他们将创建可逆的共价体系，其他研究人员可以直接用于他们自己的需求。第二，也许还有更广泛的意义，他们将展示一种揭示催化方法的方法，其他化学家也可以为他们的目标采用这种方法。除了科学进步，德克萨斯大学奥斯汀分校(UT)还为更广泛的影响提供了独特的环境。这所大学为本科生开设了一个新生研究计划(FRI)实验室，其中Anslyn博士总是与这个实验室的一部分平行，以补充他对NSF的资助。这个实验室由德克萨斯大学提供设备和赞助，因此NSF的资金被用来在一个真正以研究为导向的环境中教育一年级的化学学生。

With the support of the Chemical Structure, Dynamics, and Mechanism Program of the National Science Foundation, Professor Eric Anslyn of the University of Texas at Austin will lead a research program focused on dynamic covalent bonding. Four modern areas of chemistry are currently exploiting dynamic covalent bonding: supramolecular chemistry, Dynamic Combinatorial Chemistry (DCC), organocatalysis, and enzyme inhibition. However, the dynamic reactions routinely exploited in these areas are limited. This is due to the fact that most reactions involving reversible covalent bonding are very slow to equilibrate, and therefore exchange components on a time scale that is impractical. Our goal is to expand the number of reversible systems that are practical. To do this, the Anslyn team will first explore the mechanisms of four reversible covalent reactions, capitalize on successes that their group has recently had in this endeavor, and finally devise catalytic methods to speed up the reversible covalent interchange. The four reversible reactions they will target are: thiol conjugate addition, acetal formation, hemiaminal ether formation, and phosphinite transesterification. Understanding the mechanisms of these four reactions and uncovering methods for their catalysis will have a broad impact on the chemical community for two reasons. Firstly, they will create reversible covalent systems that other investigators can directly use for their own needs. Second, and maybe of even broader significance, they will demonstrate an approach for uncovering methods of catalysis that other chemists can also adopt for their goals. In addition to the scientific advances, the University of Texas (UT) at Austin offers a unique environment for broader impact. This University runs a Freshman Research Initiative (FRI) laboratory for undergraduates, wherein Dr. Anslyn always parallels a portion of this laboratory to complement his NSF funding. This laboratory is equipped and sponsored by UT, and thereby the NSF funding is leveraged to educate freshman chemistry students in a truly research oriented setting.