美国弗吉尼亚大学Robert J Gilliard团队的一项最新研究成功分离出一种含s区元素多重键的铍-亚胺复合物。相关论文发表在2021年1月07日出版的《德国应用化学》杂志上。

在该文中，研究人员报道了一种铍-亚胺（Be=N）复合物(2)的合成、分子结构和计算分析，该化合物的合成是通过一种分子Be(0)前驱体(1)和叠氮三甲基硅烷Me₃SiN₃（TMS-N₃）之间的氧化反应实现的。

值得注意的是，化合物2中有着目前已知最短的Be=N键（1.464 Å）。这代表着第一个有s区金属-氮多重键的化合物。所有的化合物都通过多核核磁波谱（¹H, ¹³C, ⁹Be）和单晶X射线衍射研究得到了实验表征。研究人员还通过密度泛函理论计算对它们的成键模式进行了分析，该分析支持铍原子和氮原子间存在一个π键的可能性。

据介绍，参与多重键是d区和p区元素的普遍特征，但相比之下，含s区元素同核/异核多重键的化合物的合成则非常罕见。

附：英文原文

Title: s‐Block Multiple Bonds: Isolation of a Beryllium Imido Complex

Author: Guocang Wang, Jacob Walley, Diane Dickie, Andrew Molino, David Wilson, Robert J Gilliard

Issue&Volume: 07 January 2021

Abstract: A common feature of   d  ‐ and   p  ‐block elements is that they participate in multiple bonding.  In contrast, the synthesis of compounds containing homo‐ or hetero‐nuclear multiple bonds involving s‐block elements is extremely rare. Herein, we report the synthesis, molecular structure, and computational analysis of a b eryllium imido (Be=N) complex (  2  ), which was prepared   via   oxidation of a molecular Be(0) precursor (  1  ) with trimethylsilyl azide Me  3  SiN  3   (TMS‐N  3  ). Notably, compound   2   features the shortest known Be=N bond (1.464 ) to date . This represents the  first compound with an s‐block  metalnitrogen multiple bond. All compounds were characterized experimentally with multi‐nuclear NMR spectroscopy (  1  H,   13  C,   9  Be) and single‐crystal X‐ray diffraction studies. The bonding situation was analyzed with density functional theory (DFT) calculations,  which supports the existence of   π  ‐bonding between beryllium and nitrogen.

DOI: 10.1002/anie.202016027

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202016027