Neutral zero-valent s-block complexes with strong multiple bonding
Neutral zero-valent s-block complexes with strong multiple bonding
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DOI：
10.1038/nchem.2542
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发表时间：
2016-09-01
期刊：
影响因子：
21.8
通讯作者：
Schuster, Julia K.
中科院分区：
文献类型：
--
作者：
Arrowsmith, Merle;Braunschweig, Holger;Schuster, Julia K.
众所周知，元素周期表s区的金属是特殊的电子供体，因此它们的绝大多数分子络合物都含有完全氧化形式的这些金属。低价主族化合物由于其有趣的反应性，有时与过渡金属配合物的反应性相当，最近成为理想的合成目标。在这项工作中，我们使用稳定的环状（烷基）（氨基）卡宾配体的分离和表征的第一个中性化合物，含有零价的s-块金属，铍。这些颜色鲜艳的配合物显示非常短的铍-碳键长和线性铍配位几何形状，表明强多Be-C键。结构、光谱和理论计算结果表明，配合物均为以Be（o）金属为中心的单重态结构。该分子令人惊讶的稳定性可以归因于C-Be-C单元上异常强的三中心两电子p键。
The metals of the s block of the periodic table are well known to be exceptional electron donors, and the vast majority of their molecular complexes therefore contain these metals in their fully oxidized form. Low-valent main-group compounds have recently become desirable synthetic targets owing to their interesting reactivities, sometimes on a par with those of transition-metal complexes. In this work, we used stabilizing cyclic (alkyl)(amino)carbene ligands to isolate and characterize the first neutral compounds that contain a zero-valent s-block metal, beryllium. These brightly coloured complexes display very short beryllium-carbon bond lengths and linear beryllium coordination geometries, indicative of strong multiple Be-C bonding. Structural, spectroscopic and theoretical results show that the complexes adopt a closed-shell singlet configuration with a Be(o) metal centre. The surprising stability of the molecule can be ascribed to an unusually strong three-centre two-electron p bond across the C-Be-C unit.