SusChEM: CAREER: Synthesis of Macrocyclic Carbene Complexes for Catalytic Aziridination

美国国家科学基金会化学部的化学催化项目支持田纳西大学诺克斯维尔分校（UTK）的David M. Jenkins教授的研究工作，以探索使用有机叠氮化物（包括芳基和烷基变体）作为亚硝基源和烯烃作为碳源的新型叠氮化反应。这个创新的反应涉及由强西格玛供体大环四氮杂环碳烯（NHCs）作为辅助配体的新型过渡金属配合物，作为均相叠氮化催化剂。研究分四个步骤完成：四羰基与第一和第二行过渡金属（特别是铁）的连接，有机叠氮化物与烯烃之间叠氮化反应的催化研究，通过中间体探针（即金属亚胺配合物）对反应的机理研究，以及扩大底物范围使反应与工业，制药和生物应用相关。这项工作的更广泛的影响包括为中心高中（CHS）的大学预科学者提供机会，中心高中是田纳西州诺克斯维尔市一所经济条件较差的高中，在UTK进行研究。在CHS的高中教师和诺克斯县学区的合作者的帮助下，在AP化学课程的指导下，与Jenkins教授的研究兴趣相匹配的新AP实验室正在开发中。正在提高卫生中心的实验室能力，以支持新的实验。最后，除了典型的技术介绍和出版物外，这些研究成果还通过UTK足球比赛的赛前展示进行传播。叠氮吡啶化合物存在于天然产物中，如丝裂霉素和叠氮霉素，它们具有抗肿瘤和抗生素特性，对开发新药物产品至关重要。尽管用途众多，但由于需要在最终产品中未充分利用的额外试剂，叠氮化合物的合成既浪费又昂贵。这个CAREER项目利用较便宜的金属基催化过程来避免对昂贵试剂的需要。改进后的反应有望对生物学和合成有机化学，特别是新药的制备产生影响。在与田纳西州诺克斯维尔中央高中的教师和管理人员的合作中，詹金斯教授强调了在为大学先修课程（AP）化学课程开发新实验室时使用可持续过程。詹金斯教授在技术期刊上发表他的研究成果，但也在非传统论坛上传播他的团队的成果，比如在田纳西大学诺克斯维尔足球比赛的赛前展示会上。

The Chemical Catalysis Program of the NSF Division of Chemistry supports the research efforts of Professor David M. Jenkins of the University of Tennessee at Knoxville (UTK) to explore new aziridination reactions using organic azides (both aryl and alkyl variants) as the nitrene source and alkenes as the carbon source. This innovative reaction involves novel transition metal complexes supported by strong sigma-donor macrocyclic tetra-N-heterocyclic carbenes (NHCs) as auxiliary ligands which act as homogeneous azirdination catalysts. The research is accomplished in four steps: ligation of tetracarbenes to first and second row transition metals (especially iron), catalytic studies of aziridination reactions between organic azides and alkenes, mechanistic studies of the reaction through probes of intermediates (i.e., metal imide complexes), and expansion of substrate scope to make the reactions relevant to industrial, pharmaceutical, and biological applications. The broader impacts of this work include providing opportunities for pre-college scholars from Central High School (CHS), an economically-disadvantaged high school in Knoxville, TN, to perform research at the UTK. With the assistance of high school teachers at CHS and collaborators in the Knox County School District, new Advanced Placement (AP) laboratories that match Professor Jenkins's research interests are being developed within the guidelines of the AP Chemistry curriculum. The laboratory capabilities at CHS are being upgraded in order to support the new experiments. Finally, in addition to the typical technical presentations and publications, these research results are being disseminated though the Pre-Game Showcase at UTK football games.Aziridine compounds are found in natural products, such as mitomycins and azinomycins, that have antitumor and antibiotic properties crucial to the development of new pharmaceutical products. Despite the myriad of uses, the synthesis of aziridine compounds has been wasteful and expensive due to the need for additional reagents that are not fully used in the final products. This CAREER project utilizes less expensive metal-based catalytic processes to avoid the need for expensive reagents. The improved reactions are expected to have impact in biology and synthetic organic chemistry, particularly in the preparation of new medicines. In his work with teachers and administrators at Central High School in Knoxville, Tennessee, Professor Jenkins stresses the use of sustainable processes in the development of new laboratories for the Advanced Placement (AP) Chemistry courses. Professor Jenkins publishes his work in technical journals but also disseminates his group's results in non-traditional forums, such as the Pre-Game Showcase at the University of Tennessee Knoxville football games.