CAREER: Stoichiometric and Catalytic Reaction Transformations at Group 10 Zwitterions Supported by Bis(phosphino)borate Ligands

加州理工学院化学系的Jonas Peters博士因其在研究中性两性离子复合物是否可以介导通常由阳离子配位不饱和复合物催化的反应方面的工作而获得美国国家科学基金会化学部无机、生物无机和有机化学项目的支持。 这些方法在工业上很重要，包括：聚合物材料的定制合成;对有机合成和药物开发至关重要的催化键形成反应;以及与简单烃原料的利用相关的活化和官能化化学。两性离子策略使用（膦基）硼酸盐配体来有效地将硼酸盐抗衡阴离子束缚到阳离子金属中心。 两性离子方法的潜在优点是：1）两性离子催化剂消除了对抗衡阴离子助催化剂的需要，并使抗衡阴离子结合最小化，从而简化了基本机理研究。 2)两性离子在相对非极性的溶剂介质中应是可溶的和催化活性的;然而，通常需要更多的配位溶剂来溶解阳离子催化剂，使其活性较低。 3)因为中性的两性离子络合物预期比它们的阳离子对应物更不亲电，所以它们应该在需要损失供体配体作为速率决定步骤的催化体系中增加反应速率。 两性离子模型系统的初步研究支持了这些假设。教育将通过使用案例研究方法与研究相结合，以理解和解决无机化学前沿课题中的问题。 交互式软件，在研究工作中使用的实验系统进行理论计算，也将用于课程补充，以教分子轨道理论及其在无机化学中的实际应用。 一个先进的实验室合成课程，以补充无机化学讲座课程将开发。 该研究小组将通过实验室图尔斯参观、实验室演示和非正式讨论，继续向帕萨迪纳和洛杉矶学区的当地小学生和高中生开展推广工作，以一种为年轻学生提供许多机会的方式传达对科学的热情。 它们的反应途径将被确定，以期优化催化体系。 教育计划与这项研究相结合，并延伸到本科课程和地区小学和高中学生。

Dr. Jonas Peters, Department of Chemistry, California Institute of Technology is supported by the Inorganic, Bioinorganic and Organometallic Chemistry program of the Division of Chemistry, National Science Foundation, for his work under a CAREER Award to investigate whether neutral, zwitterionic complexes can mediate reactions typically catalyzed by cationic, coordinatively unsaturated complexes. Such processes are industrially important and include: the tailored synthesis of polymeric materials; catalytic bond forming reactions critical to organic synthesis and pharmaceutical drug development; and activation and functionalization chemistry, relevant to the utilization of simple hydrocarbon feedstocks. The zwitterionic strategy uses (phosphino)borate ligands to effectively tether a borate counter-anion to a cationic metal center. The potential advantages of the zwitterionic approach are: 1) Zwitterionic catalysts remove the need for a counter-anion cocatalyst and minimize counter-anion binding thereby simplifying the fundamental mechanistic studies. 2) The zwitterions should be both soluble and catalytically active in relatively non-polar solvent media; whereas, more coordinating solvents are typically required to solubilize cationic catalysts, rendering them less active. 3) Because neutral, zwitterionic complexes are expected to be less electrophilic than their cationic counterparts, they should increase reaction rates in catalytic systems that require loss of a donor ligand as a rate-determining step. Preliminary studies with zwitterionic model systems lend support to these hypotheses.Education will be integrated with research by using a case studyapproach for understanding and solving problems in frontier topics in inorganic chemistry. Interactive software, used in the research effort to perform theoretical calculations on experimental systems, will also be used in a course supplement to teach molecular orbital theory and its practical application in inorganic chemistry. An advanced laboratory synthesis course to complement the lecture course in inorganic chemistry will be developed. The research group will continue its outreach efforts to local elementary and high school students in the Pasadena and Los Angeles school districts by using laboratory tours, laboratory demonstrations, and informal discussions to communicate enthusiasm for science in a way that suggests many opportunities for younger students.Simplified analogs of industrially important catalysts will be developed. Their reaction pathways will be determined with a view toward optimizing catalytic systems. The educational program is integrated with this research and extends to undergraduate courses and area elementary and high school students.