金属-碳多重键因其特殊的成键性质及其产物良好的应用前景而备受关注。五元环内高张力金属-碳多重键（本项目特指金属亚乙烯基和金属卡拜）因其极端不稳定而成为挑战。成功分离的这类化合物极为罕见，该化学尚处在萌芽状态：金属品种稀少（目前仅有Os）；尚无通用且简便的合成路线；结构种类匮乏；反应性亟待研究。我们对这类化合物的前期研究已初步展示其独特的物理化学性质，应用前景良好。.在我们已构筑一系列高稳定性金属杂环的基础上，本项目旨在构筑一系列具有一定稳定性的五元环内高张力金属-碳多重键骨架，拓展其过渡金属品种（优先考虑拓展到Ru、Rh、Ir等高催化活性的金属），结合理论计算促进对基于金属-碳多重键过程的重要有机反应机理的理解，开展物理化学性能和应用研究，开发全新的金属-碳多重键试剂并导向新型的有机合成反应，藉此推动金属-碳多重键化学及相关有机合成化学的发展。本项目还将考察产物的光电磁等性能及其应用前景。

Complexes with metal-carbon multiple bonds have attracted extensive attention because of their unique properties and important applications in organic synthesis. The synthesis of high strained five-membered metallacycles containing metal-carbon multiple bonds, which are only referred to the vinylidene complexes and metal carbyne complexes in this project, has been regarded as big challenge due to the highly unstability. In comparison with that of acyclic complexes with metal-carbon multiple bonds, the chemistry of the high strained cyclic complexes with metal-carbon multiple bonds is less developed. To date, the reported metal centers are only the osmium atoms, and the general and convenient methods are still unavailable. In addition, both the structure diversity and the reactivity study of these complexes are deficient. Our preliminary study demonstrated that these complexes display unique properties and promising applications..This proposed project focuses on the high strained five-membered metallacycles with metal-carbon multiple bonds based on our previous study of the highly stable metallacycles. We plan to investigate both computationally and experimentally how the synthesis of the high strained metallacycles with metal-carbon multiple bonds can be efficient achieved and how these compounds can be exploited based on their electronic characteristics and structural features. These investigations may provide new insights into the mechanisms of some important reactions involving the intermediates with metal-carbon multiple bonds. From these investigations, we also hope to obtain new organometallic reagents directed to new organic reactions. We will also study the optical, electronical and magnetic properties of these compounds, thus building up the structure-property relationship towards the application.