SusChEM: Metal Complexes Containing New Tin Ligands for Applications in Homogeneous Catalysis

获得化学系化学合成(SYN)项目的这一奖项后，迈阿密大学化学系主任Burjor教授将探索含有大量锡配体的过渡金属络合物的结构和反应活性。主要的驱动力是指示氢和小分子的活化，以及研究它们作为氢甲酰化和氢化催化剂的潜力。这项工作将包括结合空间位阻的锡配体，以在过渡金属络合物中的金属原子周围产生电子和/或配位不饱和。这项工作将从探索铂-锡体系的合成、结构和催化化学开始，然后扩展到包括非贵金属过渡金属的络合物，如镍和铁。中心主题是锡的使用，这提供了巨大的优势，而且在很大程度上未经测试。这一策略的潜在范围和有效性在被广泛研究的膦配体用于修饰结合部位和催化性质方面是有先例的。然而，与膦配体相比，笨重的锡配体为他们的研究提供了额外的激励。由于锡基是具有奇数个电子的自由基，它在金属位置的利用改变了形式氧化数，但更重要的是，金属中心的电子密度以与配位膦完全不同的方式改变。这项工作的长期目标是开发用于化学工业的坚固、经济和高效的催化剂。该项目的更广泛影响是，它要求在一个相对未知的无机化学领域合成一类新的材料。这为发现小分子的新结合模式提供了机会。其中一些可能是可预测的，但另一些可能是意想不到的，并导致对基础化学科学产生广泛影响的新见解。主族化学有了复兴，这项工作结合了主族和过渡金属化学在一个令人兴奋的和潜在的突破性领域。拟议的小分子活化研究以氢为中心-试图了解它在主族金属-过渡族金属环境中的行为。过渡金属络合物已经并将一直在氢的化学中发挥关键作用，但这种作用可能会被添加的大体积锡配体的存在所改变。问题是，它将如何修改，修改的程度如何。这项工作的长期影响将是帮助更好地利用这一结合和催化活性方面的重要资源。最后一个影响领域是学生(本科生和研究生)成为科学家和专业人员的培训。学生将接受准备和操作空气敏感化合物的培训，并将学习各种方法，如X射线结晶学、傅立叶变换红外光谱、核磁共振光谱、质谱学、量热法和计算分析。结果将在被引用的研究期刊上广泛传播，并通过在会议上的陈述进行传播。由于拟议研究的多样性，接受该项目培训的学生将拥有为新出现的能源危机找到可行的解决方案并为可持续发展做出贡献所需的技能和创造性态度。

With this award from the Chemical Synthesis (SYN) Program of the Chemistry Division, Professor Burjor Captain of the Department of Chemistry at the University of Miami will explore the structures and reactivity of transition metal complexes containing bulky tin ligands. The main drive is to indice activation of hydrogen and small molecules as well as to investigate their potential as hydroformylation and hydrogenation catalysts. The work will consist of incorporating sterically encumbered tin ligands to bring about electronic and/or coordinative unsaturation around the metal atoms in transition metal complexes. This work will begin by exploring synthetic, structural, and catalytic chemistry on platinum-tin systems and then be extended to include complexes of non-precious transition metals such as Ni and Fe. The central theme is the use of tin which offers significant advantages and is largely untested. There is precedent for the potential scope and effectiveness of this strategy in the widely investigated use of phosphine ligands to modify both binding sites and catalytic properties. However, bulky tin ligands offer additional incentives for their investigation compared to phosphine ligands. Because the stannyl group is a radical with an odd number of electrons, its utilization at a metal site changes formal oxidation numbers, but more importantly electron densities at the metal center, in ways quite different from that of coordinated phosphines. The long range goal of this work is development of robust, economic, and efficient catalysts of use to chemical industry.The broader impact of this project is that it calls for synthesis of a new class of materials in a relatively unexplored area of inorganic chemistry. This provides the opportunity to discover new binding patterns of small molecules. Some of these may be predictable, but some may be unanticipated and lead to new insights of broad impact in fundamental chemical science. There has been a renaissance in main group chemistry, and this work combines main group with transition metal chemistry in an exciting and potentially breakthrough area. The proposed small molecule activation studies center on hydrogen- by trying to understand how it behaves in a main group metal-transition group metal setting. Transition metal complexes have and always will play the crucial part in the chemistry of hydrogen, but this may be modified by the presence of the added bulky tin ligand. The question is how and to what extent it will be modified. The long term impact of this work will be in helping to better utilize this important resource in binding and catalytic reactivity. A final area of impact is in student training (undergraduate and graduate) to be scientists and professionals. Students will be trained to prepare and handle air-sensitive compounds, and will learn various methods such as X-Ray crystallography, Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, mass spectrometry, calorimetry and computational analysis. The results will be broadly disseminated in refereed research journals and through presentations at meetings. Due to the diversity of the proposed research, students trained in this program will have the skill set and creative attitude needed to find viable solutions for the emerging energy crisis and contribute to sustainability.