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

NSF化学部的化学催化计划支持田纳西大学诺克斯维尔分校(UTK)的David M.Jenkins教授的研究努力，以有机叠氮化物(芳基和烷基变体)为氮源，烯烃为碳源，探索新的氮杂化反应。这一创新的反应包括以强Sigma供体大环四氮杂环卡宾(NHCS)为辅助配体的新型过渡金属络合物作为均相氮化催化剂。该研究分四个步骤完成：四碳联苯与第一和第二排过渡金属(特别是铁)的连接，有机叠氮化合物与烯烃之间氮杂环化反应的催化研究，通过中间体(即金属酰亚胺络合物)的探针对反应机理的研究，以及扩大底物范围使反应与工业、医药和生物应用相关。这项工作的更广泛的影响包括为中央高中(CHS)的大学前学者提供机会，中央高中是田纳西州诺克斯维尔的一所经济困难的高中，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，正在根据AP化学课程的指导方针开发符合詹金斯教授研究兴趣的新的AP实验室。CHS的实验室能力正在升级，以支持新的实验。最后，除了典型的技术报告和出版物外，这些研究成果还通过UTK足球比赛的赛前展示进行传播。阿齐里丁化合物存在于丝裂霉素和阿奇霉素等天然产品中，这些天然产品具有抗肿瘤和抗菌特性，对新药物的开发至关重要。尽管用途繁多，但氮杂环丙烷化合物的合成一直是浪费和昂贵的，因为需要额外的试剂，而这些试剂在最终产品中没有完全使用。这个职业项目使用成本较低的基于金属的催化工艺，以避免需要昂贵的试剂。预计改进后的反应将对生物学和合成有机化学产生影响，特别是在新药的制备方面。在与田纳西州诺克斯维尔中心高中的教师和管理人员的合作中，詹金斯教授强调了在为高级选修(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结果，比如田纳西诺克斯维尔大学的赛前展示足球比赛。

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.