甲 ((di-tert-butylmethylsilyl) distannene及其离子基和其离子基
Tomohide Fukawa1, Vladimir Ya Lee, Masaaki Nakamoto
1Department of Chemistry, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan.
Journal of the American Chemical Society
|September 24, 2004
概括
合成了tetrakis ((di-tert-butylmethylsilyl) distannene,揭示了最短的锡-锡双键. 这种稳定的化合物不会分裂成斯坦尼烯,并形成一个独特的离子基.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 迪斯坦是稳定的化合物,含有锡-锡双键.
- 由于其独特的结合和反应性,环二基具有兴趣.
- 了解它们的稳定性和电子特性对于开发新材料和催化剂至关重要.
研究的目的:
- 为了合成和表征一种新型的非循环迪斯坦,Tetracis ((di-tert-butylmethylsilyl) 迪斯坦 (1).
- 为了研究结构性质,特别是Sn=Sn键的长度和几何.
- 探索合成的迪坦的反应性和电子行为,包括其解离和减少.
主要方法:
- 在THF中通过tBu2MeSiNa与SnCl2-二氧化物的合反应合成.
- 用X射线结晶学测定迪斯坦及其离子基的结构.
- 与四化碳 (CCl4) 发生反应以探测解离.
- 用进行单电子还原,并通过ESR光谱学进行表征.
主要成果:
- 甲 (Tetracis(di-tert-butylmethylsilyl) distannene (1) 已成功合成并分离为深绿色的晶体.
- X射线分析显示,在非循环距离体中,Sn=Sn双键 (2.6683(10) A) 是最短的,具有几乎平面且高度扭曲的几何形状.
- 化合物1在与CCl4的反应中没有分裂成斯坦尼,表明在固态和溶液中的稳定性.
- 一个电子的减少产生了一个稳定的distanene离子基 (3),其特点是X射线晶体学和ESR光谱学.
结论:
- 合成的Tetracis ((di-tert-butylmethylsilyl) distannene具有特殊的结构特征,包括最短的Sn=Sn键.
- 该化合物表现出显著的稳定性,抵抗分裂成斯坦尼.
- 稳定的二二离子基的形成和表征为重类同类及其基质化学提供了洞察力.
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