南方科技大学夏海平团队报道了具有五个共面金属-碳 σ键的过渡金属配合物形成的实验和理论证据。相关研究成果发表在2023年12月20日出版的《国家科学评论》。

σ键是化学中的一个重要概念，尤其是金属-碳（M–C）σ键是有机金属化学的一个核心特征。合成具有五个共面M–C σ键的稳定配合物具有挑战性。

该文中，研究人员描述了合成的两种不同稳定类型的具有五个共面M–Cσ键的配合物，并检测了这种使用刚性共轭碳链与金属中心螯合的配合物的稳定性。密度泛函理论（DFT）计算表明，这些配合物中的M–C σ键主要具有共价性质。除了σ性质外，金属中心和碳之间还存在π共轭成分，从而导致了离域。

该项工作将共面的M–C σ键扩展到五个。

附：英文原文

Title: Experimental and theoretical evidences for the formation of transition metal complexes with five coplanar metal–carbon σ bonds

Author: Hua, Yuhui, Luo, Ming, Lu, Zhengyu, Zhang, Hong, Chen, Dafa, Xia, Haiping

Issue&Volume: 2023-12-20

Abstract: The σ bond is an important concept in chemistry, and the metal–carbon (M–C) σ bond in particular is a central feature in organometallic chemistry. Synthesis of stable complexes with five coplanar M–C σ bonds is challenging. Here, we describe our synthesis of two different stable types of complexes with five coplanar M–C σ bonds, and examine the stability of such complexes which use rigid conjugated carbon chains to chelate with the metal center. Density functional theory (DFT) calculations showed that the M–C σ bonds in these complexes have primarily a covalent character. Besides the σ nature, there are also π conjugation component among the metal center and carbons, which causes delocalization. This work expanded the coplanar M–C σ bonds to five.

DOI: 10.1093/nsr/nwad325

Source: https://dx.doi.org/10.1093/nsr/nwad325