Establishing Bonding and Reactivity in Organometallic Uranium Species

该项目由化学部化学合成计划资助。普渡大学教授苏珊娜·巴特研究铀的有机金属化学。有机金属化学是研究含有金属-碳键的化合物，在药物、材料和精细化学品方面的许多进展都是以有机金属化学为基础的。虽然铀的行为已经被研究了很多年，但它的有机金属化学仍然相当有限。一般来说，金属可以与碳形成一个、两个或三个化学键。本研究制备了含铀碳双键的化合物，并考察了它们的反应活性。在这些发现的基础上，还制备了具有铀、硅和铀-氮双键的化合物。这些研究为今后铀新应用的开发奠定了基础。此外，该项目还培训铀化学本科生和研究生。这一点极其重要，因为铀化学劳动力正在老龄化，目前接受该领域培训的年轻科学家很少。巴特教授和她的学生还为高中教师组织了一个科学夏令营，他们的目标是通过动手活动和设计新的演示，让教师掌握铀化学的新技能。以空间大体积的氢化(二甲基吡唑基)硼酸盐为支撑体，形成铀双(烷)基化合物作为合成子，制备了铀-烷基烯、-硅烯和-亚胺配合物。这些化合物使用多种分析技术进行了表征，包括多核核磁共振、红外和电子吸收光谱，以及X射线结晶学和计算方法。用氢原子转移研究评价了铀-氮键的强度，估算了铀-氮多键的键强度，并从理论上考察了f轨道在多键中的作用。一项外展计划在科学夏令营中引入了榄系元素化学。

This project is funded by the Chemical Synthesis program of the Chemistry Division. Professor Suzanne Bart, Purdue University, studies the organometallic chemistry of uranium. Organometallic chemistry is the study of compounds that contain metal-carbon bonds and many advances in pharmaceuticals, materials, and fine chemicals are based on organometallic chemistry. While the behavior of uranium has been studied for many years, its organometallic chemistry remains quite limited. In general, metals can form one, two, or three chemical bond to carbon. This study prepares compounds containing uranium carbon double bonds and investigates their reactivity. Building on these findings compounds with uranium silicon and uranium-nitrogen double bonds also are prepared. These studies lay the ground work for the future development of new applications for uranium. In addition, the project trains undergraduate and graduate students in uranium chemistry. This is extremely important as the uranium chemistry workforce is aging and very few young scientists currently receive training in the field. Prof. Bart and her students also organize a science summer camp for high school teachers where they aim to give the teachers new skills in uranium chemistry through hands on activities and the design new demonstrations. Using sterically bulky hydrotris(dimethylpyrazoly)borate as supporting ligands, uranium bis(alkys) are formed as used as synthons to prepare uranium-alkyledene, -silene, and -imido complexes. These compounds are characterized using multiple analytical techniques, including multinuclear NMR, infrared, and electronic absorption spectroscopies, as well as X-ray crystallography and computational methods. The strength of the uranium-nitrogen bonds is assessed using hydrogen atom transfer studies the bond strength of the uranium-nitrogen multiple bonds are assessed and the role of f-orbitals in the multibonds is examined theoretically. An outreach program introduces actinide chemistry into a science summer camp.