研究室工作进展 Nov. 1st, 2013

 Coordination-Induced Skeletal Rearrangements of Zirconacyclobutene-Silacyclobutene Fused Complexes

 Jing Zhao, Shaoguang Zhang, Wen-Xiong Zhang, and Zhenfeng Xi*
Coord. Chem. Rev. 2013, DOI: http://dx.doi.org/doi:10.1016/j.ccr.2013.08.032
 
    Coordination-induced skeletal rearrangement of transition-metal complexes is of fundamental interest both synthetically and mechanistically. Besides commonly observed ligand substitution, the coordination of ligands may greatly alter the steric and electronic environment around the metal center, thus activating the whole compound, resulting in novel rearrangement or cleavage of chemical bonds. Subsequent formations of chemical bonds would lead to synthetically useful methods for new transition-metal complexes and organic compounds. Zirconacycles have been proved to be very useful for synthetic organic and organometallic chemistry. The present review concentrates on the coordination-induced skeletal rearrangement of zirconacyclobutene-silacyclobutene fused complexes. When treated with nitriles, alkynes, ketones, or other unsaturated organic molecules, the zirconacyclobutene-silacyclobutene fused complexes underwent the coordination-induced rearrangement and new chemical bond forming process, other than the expected direct insertion reactions. Different types of rearrangements were observed depending on the coordinating unsaturated organic molecules. A variety of zirconacycles and organic products were formed efficiently from the zirconacyclobutene-silacyclobutene fused complexes and the unsaturated organic molecules through the coordination-induced rearrangement and new chemical bond forming process.
 
背景介绍
        化学反应活性中间体的分离与结构表征对于理解反应机理具有重要意义,而反应机理研究是化学研究的核心内容之一。通过对活性中间体的结构表征,不仅有助于深入理解反应机理,同时有助于设计新反应,建立新方法,实现新的有机合成方法。金属杂环化合物是许多重要反应中的中间体。本小组通过合成、分离金属(如钛、锆、铝、镁等)杂五元环以及金属杂四元环活性中间体,在理解相应反应的机理的同时,利用这些活性中间体,发展了一系列有机合成新方法,合成得到其它方法难于合成的新型金属有机化合物以及结构多样的环状有机化合物。2007年我们应邀在Chem. Soc. Rev. 上系统总结了本实验室在金属有机杂化试剂与路易斯酸的“协同效应”研究工作结果(Congyang Wang and Zhenfeng Xi,* Chem. Soc. Rev. 2007, 36, 1395-1406.)。
        2011年本小组应邀在Acc. Chem. Res. 上系统总结了本实验室近十年来在金属杂环试剂与有机底物的“协同效应”研究方面的工作结果(Wen-Xiong Zhang, Shaoguang Zhang, and Zhenfeng Xi,* Acc. Chem. Res. 2011, 44, 541-551)。该文详细阐述了一些金属有机活性中间体与有机底物间的“协同效应”,以及本实验室“基于机理研究和活性中间体的合成化学”研究理念。
        本文应Coord. Chem. Rev.“金属有机化学前沿”特辑的邀请,从配位化学基本反应的角度,介绍了本实验室10余年来开展的锆杂环丁烯并硅杂环丁烯化合物在不同配体的配位诱导作用下发生的一系列骨架重排反应及机理研究结果。