Interplay between stable carbenes and neutral group-13 element nucleophiles, organic radicals, and strong bases

在这个由化学部化学结构、动力学机制B计划资助的项目中，加州大学圣地亚哥分校（UCSD）化学与生物化学系的Guy Bertrand教授将制备过渡金属催化剂的原始配体和新型稳定自由基。需要富电子配体的无数催化应用将受益于将被合成的13族元素物种。自由基参与许多化学和生物过程，它们的稳定化将使人们更好地了解它们的性质。该项目是物理，有机，无机和有机金属化学之间的接口;因此，它非常适合各级科学家的教育。首席研究员的实验室是UCSD和法国国家科学研究中心的合资企业。它有助于促进UCSD和欧洲大学之间的本科生和研究生的交流。多年来，过渡金属催化剂的“定向L”配体是基于第15和16族元素。N-杂环卡宾的引入，以及因此基于第14族元素的辅助配体的引入，已经产生了许多突破。这是卡宾的强σ-供体性质的结果，这是由于与第15族和第16族元素相比，碳的电负性较低。与胺和卡宾等电子，但基于电负性甚至小于C的B、Al和Ga的配体将是极强的电子供体配体。亲电稳定的卡宾也将用于制备稳定的有机自由基和多自由基。 自由基稳定性的应用将是发现高效、无毒的氢供体。最后，亚氨基和叶立德取代基，来自新发现的非亲电mesoionic卡宾，将用于制备强中性碱和氢化物供体。

In this project funded by the Chemical Structure, Dynamic & Mechanism B Program of the Chemistry Division, Professor Guy Bertrand of the Chemistry and Biochemistry Department at the University of California - San Diego (UCSD), will prepare original ligands for transition metal catalysts and novel stable radicals. The myriad of catalytic applications requiring electron-rich ligands will benefit from the group 13 element species that will be synthesized. Radicals are involved in numerous chemical and biological processes, and their stabilization will allow for a better understanding of their properties. This project is at the interface between physical, organic, inorganic and organometallic chemistry; therefore it is well suited to the education of scientists at all levels. The laboratory of the principal investigator is a joint venture between UCSD and the French National Centre for Scientific Research. It serves to promote the exchange of undergraduates and graduates between UCSD and European Universities.For years the "directing L" ligands of transition metal catalysts were based on the elements of groups 15 and 16. The introduction of N-Heterocyclic Carbenes, and thus of ancillary ligands based on a group 14 element, has generated many breakthroughs. This is the result of the strong sigma-donor properties of carbenes, which are due to the lower electronegativity of carbon compared to group 15 and 16 elements. Ligands, which are isoelectronic with amines and carbenes, but based on B, Al and Ga that are even less electronegative than C, will be extremely strong electron-donor ligands. Electrophilic stable carbenes will also be used for preparing stable organic radicals and polyradicals. An application, resulting from the stability of radicals, will be the discovery of efficient, non-toxic, hydrogen donors. Lastly iminato and ylide substituents, derived from the newly discovered non-electrophilic mesoionic carbenes, will be used for the preparation of strong neutral bases and hydride donors.