New Reactions for Utilizing N and P Atoms Derived Directly from the Elements

麻省理工学院化学系Christopher C.Cummins博士得到化学部无机、生物无机和有机金属计划的支持，以开发利用直接从元素中提取的氮和磷原子的新反应。利用氮或磷与Nb或Mo三键结合的络合物，三键复分解将被开发为合成有机氮和磷化合物的一种途径。目标包括磷杂炔、腈和酰亚胺化合物。这些金属络合物还将被探索为卡宾捕捉剂，可以进行β消除以产生包括腈在内的物种。基于这些结果，将制备与元素氮和/或磷反应形成金属-氮或磷络合物的催化和化学计量体系，这些络合物将进行具有合成价值的反应。这一化学将扩展到金属-碳三键的催化和化学计量反应。一个目标是探索钼-碳三键化学应用于合成含有烯二炔官能团的分子。地球大气中最丰富的元素是氮。虽然大自然能够在生物系统中利用大气中的氮，但现代化学科学仍在寻找经济地利用元素氮的技术。该项目源于最近发现的钼和铌化合物，它们可以在温和的条件下裂解氮氮中的氮-氮键。为了利用这一化学，金属辅助二氮裂解得到的氮原子将被用于制备有机氮化合物。此外，还将设计相关工艺，以使用从元素磷中提取的磷原子。这些结果将导致制备重要类别的有机磷和氮化合物的新方法。除了科学成果，该项目还将为不同的本科生、研究生、博士后和来访的高级科学家提供培训。

Dr. Christopher C. Cummins, Chemistry Department, Massachusetts Institute of Technology, is supported by the Inorganic, Bioinorganic, and Organometallic Program of the Chemistry Division for the development of new reactions that utilize nitrogen and phosphorus atoms derived directly from the elements. Using complexes in which a nitrogen or phosphorus is triply bonded to a niobium or molybdenum, triple-bond metathesis will be developed as a synthetic route to organic nitrogen and phosphorus compounds. Targets include phosphaalkynes, nitriles, and acylimido compounds. The metal complexes also will be explored as carbene trapping reagents that can undergo beta-elimination to produce species including nitriles. Based on these results, catalytic and stoichiometric systems that react with elemental nitrogen and/or phosphorus to form metal-nitrido or -phosphido complexes that will undergo synthetically valuable reactions will be prepared. This chemistry will be extended to catalytic and stoichiometric reactions of metal-carbon triple bonds. One objective is to explore molybdenum-carbon triple bond chemistry as applied to the synthesis of molecules containing the enediyne functionality.The most abundant element in the earth's atmosphere is nitrogen. While nature is able to utilize atmospheric nitrogen in biological systems, modern chemical science is still seeking technologies for the economical usage of elemental nitrogen. This project grows from the recent discovery of molybdenum and niobium compounds that can cleave the nitrogen-nitrogen bond in dinitrogen under mild conditions. In order to utilize this chemistry, the nitrogen atoms derived from metal assisted dinitrogen cleavage will be used to prepare organic nitrogen compounds. In addition, related processes will be devised to use phosphorus atoms derived from elemental phosphorus. These results will result in new ways to prepare important classes of organic phosphorus and nitrogen compounds. In addition to the scientific results, this project will provide training to a diverse group of undergraduate, graduate, postdoctoral, and visiting senior scientists.