Metallasilatranes: Palladium(II) and Platinum(II) as Lone-Pair Donors to Silicon(IV)
作者:Jörg Wagler、Erica Brendler
DOI:10.1002/anie.200905241
日期:2010.1.12
Caught by the octopus: The first structurally characterized metallasilatranes exhibit strong, formally dative Pd→Si and Pt→Si bonds (see picture; C gray, N blue, Si red, S yellow, Cl green, Pt black). The Si atoms are hexacoordinate, and the transition‐metal (TM) atom is a lone‐pair donor. Short TMSi separations, pronounced upfield 29Si NMR signals, and strong Si–Pt coupling show the interaction between
feasibility of oligosilanes with adjacent hexacoordinate Si atoms. One of the hexacoordinate Si atoms of 3 a features the unprecedented (Si2S4)Si skeleton. Natural bonding orbital (NBO) analyses of compounds 1, 2, 3 a (and the target compound 3) revealed characteristics of MII→SiIV (for 2 and 3) or MI→SiIV (for 3 a) dative bonding in the systems with M=Si and Ge, whereas compound 1 exhibits a covalent SnIII−SiIII
甲硫唑基(mt,即2-巯基-1-甲基咪唑啉)取代的硅烷Si(mt)4与SnCl 2和GeCl 2在二恶烷中的反应提供了桨轮状复合物[ClSi(μ-mt)4 MCl]( M = Sn(1)和Ge(2)。这些化合物代表在Si配位球中包含Sn或Ge原子的第一晶体学表征的六配位硅配合物。试图合成相关硅化合物3 [CLSI(μ-MT)4的SiCl]代替,得到丙硅烷[CLSI(μ-MT)4的Si 的SiCl 3 ](3一),这为具有相邻六配位Si原子的低聚硅烷的可行性提供了第一个晶体学证据。3 a的六配位Si原子之一具有前所未有的(Si 2 S 4)Si骨架。化合物的天然的键轨道(NBO)分析1,2,3一(和目标化合物3)显示M的特性II →硅IV(对于2和3)或M我→硅IV(对于3)在配价键合具有M = Si和Ge的系统,而化合物1表现出共价的Sn III -Si III键。