易斯酸介导的双价M(C(SiHMe(2)) 的β-化物抽象反应 (M = Ca, Yb)
KaKing Yan1, Brianna M Upton, Arkady Ellern
1Department of Chemistry and U.S. Department of Energy Ames Laboratory, Iowa State University, Ames, Iowa 50011-3111, USA.
Journal of the American Chemical Society
|October 3, 2009
概括
具有β-厌氧SiH组的和化合物与易斯酸发生化物抽象反应,形成意想不到的产物,排除有机金属化学中的β-消除途径.
科学领域:
- 有机金属化学 有机金属化学
- 化学 化学 化学
- 协调化学 协调化学
背景情况:
- 合成了具有β-毒性SiH组的二元和化合物.
- 这些化合物具有具有显著性特征的SiH键.
- 之前的研究表明,相关系统中可能存在β-消除途径.
研究的目的:
- 为了研究与易斯酸的M(C(SiHMe(2)) ((3)) ((2) THF(2) 化合物的反应性.
- 阐明反应机制,特别是探讨β消除与化物抽象.
- 为了描述与基易斯酸反应产生的产物.
主要方法:
- 二价和复合物的合成和表征.
- 谱分析 (例如,NMR) 和X射线晶体学以确定结构特征.
- 与易斯酸的反应,特别是B (C) (6) (F) (5) (iii) 和B (Ph) (3) 的反应,然后是产品的分离和分析.
主要成果:
- 化合物M ((C ((SiHMe ((2)) ((3)) ((2)) THF ((2) 呈现出β-厌氧的SiH组.
- 与易斯酸B,C,6F,5F,3和BPh,3的反应主要导致化物抽取,形成[HB,C6,F,5F,3]或相关的离子.
- 观察到1,3-disilacyclobutane的形成,但排除它是β-消除的产物,基于固体测量和其他产品.
结论:
- 尽管存在化SiH组和易斯酸性金属中心,但对于这些特定的M{C}{SiHMe}{2}{3}{2}THF{2}化合物而言,β消除不是可行的反应途径.
- 化物抽象是当这些化合物与易斯酸相互作用时的主导反应途径.
- 这项研究澄清了具有-化键的低坐标金属复合物的反应性景观.
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