高效地构建多种类型的alfa位官能化羰基化合物在有机合成和新药研发领域具有重要的意义。其中氮杂环卡宾催化体系由于具有高立体选择性、低毒、高效的优点而备受关注。然而，目前氮杂环卡宾催化的羰基alfa位官能团化反应局限于缺电子底物，且较难合成alfa位为C-C键、C-O键的开链化合物。针对以上问题，本项目拟利用氮杂环卡宾催化的单电子迁移反应来实现羰基alfa位的不对称官能团化。研究卡宾催化的多种羰基化合物与烯烃、烯醇硅醚、芳烃、硝基硅酯以及TEMPO等富电性或电中性底物的单电子迁移反应，期望构建出alfa位为C-C键以及C-O键的羰基化合物，并深入探讨反应机理，揭示可能的反应历程。研究成果有望提供一种在羰基alfa位高立体选择性构建多种官能团的新方法，从而丰富氮杂环卡宾催化的单电子迁移反应的理论基础。

Development of novel methodologies for the efficiently preparation of carbonyl compounds containing a stereocenter at the alfa position has great significance in organic synthesis and pharmaceutical industry. Among the various catalysts, the N-heterocyclic carbene (NHC) catalysts have attracted lots of attention due to its high stereoselectivity, low toxicity and high efficiency in manufacturing of such compounds. However, the NHC catalyzed reactions are restricted to the electron-deficient substrates and are difficult to provide non-cyclic molecules containing new C-C or C-O bonds at the alfa position. In this project, we aim to develop strategies for the alfa-functionalization of carbonyl compounds via the NHC-catalyzed single electron transfer (SET) reactions. The NHC-catalyzed SET process will be examined by the reaction of various carbonyl derivatives with electron rich or neutral substrates, such as olefins, silyl enol ethers, arenes, silyl nitronates and TEMPO, expecting to provide carbonyl compounds containing new C-C and C-O bonds. Mechanistic investigations into these types of chemistry will help uncover the possible reaction pathways. Based on the result of this research, one highly stereoselective method for the construction of alfa-stereocenter of carbonyl groups should be developed, which will aid the development of more efficient NHC-catalyzed SET reactions.