Xu Hong-Lei, Tkachenko Nikolay V, Muñoz-Castro Alvaro, Boldyrev Alexander I, Sun Zhong-Ming
State Key Laboratory of Elemento-Organic Chemistry, Tianjin Key Lab for Rare Earth Materials and Applications, School of Materials Science and Engineering, Nankai University, Tianjin, 300350, China.
Department of Chemistry and Biochemistry, Utah State University, 0300 Old Main Hill, Logan, UT, 84322-0300, USA.
Angew Chem Int Ed Engl. 2021 Apr 26;60(18):9990-9995. doi: 10.1002/anie.202102578. Epub 2021 Mar 23.
Since [Sn ] was discovered from the solid-state phase in 2000, its solution chemistry has been elusive due to the high charges and chemical activity. Herein, we report the synthesis and characterization of an inverse sandwich-type cluster dimer {[K ZnSn (ZnMes)] } (1 a), in which the highly charged [Sn ] is captured by mixed-valence Zn /Zn to form the dimer {closo-[Zn Sn ]} moieties bridged by a Zn-Zn bond. Such Zn-Sn cluster not only exhibits a novel example of mixed-valence Zn /Zn for stabilizing highly active anion species, but also indicates the [Sn ] cluster can act as a novel bridging ligand, like arene, with a η :η -fashion. Theoretical calculations indicate that a significant delocalization of electrons over Zn atoms plays a vital role in the stabilization of the [Sn ] species. The AdNDP and magnetic response analyses clearly showed the presence of local σ-aromaticity in three cluster fragments: two ZnSn caps and Sn square antiprism.
自2000年[Sn ]从固态相中被发现以来，由于其高电荷和化学活性，其溶液化学一直难以捉摸。在此，我们报道了一种反夹心型簇二聚体{[K ZnSn (ZnMes)] } (1 a)的合成与表征，其中高电荷的[Sn ]被混合价态的Zn /Zn捕获，形成由Zn-Zn键桥连的二聚体{closo-[Zn Sn ]}部分。这种Zn-Sn簇不仅展示了混合价态Zn /Zn稳定高活性阴离子物种的一个新例子，还表明[Sn ]簇可以像芳烃一样，以η :η 方式作为一种新型桥连配体。理论计算表明，电子在Zn原子上的显著离域在[Sn ]物种的稳定中起着至关重要的作用。AdNDP和磁响应分析清楚地表明，在三个簇片段中存在局域σ-芳香性：两个ZnSn帽和Sn方形反棱柱。
