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

Christopher C. Cummins博士，麻省理工学院化学系，由化学部无机、生物无机和有机金属项目支持，用于开发利用直接来自元素的氮和磷原子的新反应。利用氮或磷与铌或钼三键结合的配合物，三键复分解将发展成为有机氮和磷化合物的合成途径。目标包括磷酸烷、腈和酰基氨基化合物。金属配合物也将被探索作为碳捕获试剂，可以经过β消除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-磷配合物的催化和化学计量系统，这些配合物将进行有合成价值的反应。该化学将扩展到金属-碳三键的催化和化学计量反应。一个目标是探索应用于合成含有烯二炔功能分子的钼碳三键化学。地球大气中最丰富的元素是氮。虽然自然界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求经济利用元素氮的技术。这个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在二氮中劈裂氮-氮键。为了利用这种化学反应，金属辅助二氮裂解产生的氮原子将被用来制备有机氮化合物。此外，还将设计相关工艺，利用从单质磷中提取的磷原子。这些结果将为制备重要类别的有机磷和氮化合物提供新的方法。除了科学成果，该项目还将为本科生、研究生、博士后和访问的资深科学家提供培训。

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.