可分离的基和生殖基缺乏与pi键的结合:合成,表征和反应性
Akira Sekiguchi1, Tomohide Fukawa, Masaaki Nakamoto
1Department of Chemistry, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan. sekiguch@staff.chem.tsukuba.ac.jp
Journal of the American Chemical Society
|August 15, 2002
概括
研究人员从更重的14组元素中合成了第一个稳定的基和细菌基. 这些新型基具有平面几何形状,并容易发生化反应.
科学领域:
- 有机金属化学 有机金属化学
- 化学 化学
- 德国化学化学
背景情况:
- 稳定基对于理解反应机制至关重要.
- 较重的14组元素通常需要pi键对联以实现基结稳定.
- 缺乏pi稳定性的孤立基很少见,特别是在较重的元素中.
研究的目的:
- 合成和表征第一个可分离的silyl和germyl激素的较重的14组元素没有pi键稳定.
- 调查这些新型激进物种的结构和电子特性.
- 探索这些基因在化反应中的反应性.
主要方法:
- 三[di-tert-butyl(methyl) silyl]silyl和-germyl离子的单电子氧化,使用二甲烯-二氧化复合物.
- 进行X射线晶体学以确定激素的分子结构.
- 电子自旋共振 (ESR) 谱学用于分析根性质和超细合常量.
- 用各种基化物进行化反应.
主要成果:
- 成功合成了稳定的三[di-tert-butyl(methyl) silyl]silyl和-germyl基 (1 和 2).
- 水晶结构揭示了根中心周围的平面几何形状,表明sp2杂交.
- 通过小型超细合常量,ESR光谱证实了基的pi特征.
- 激素1和2很容易与化剂发生反应,形成相应的 halosilanes 和 halogermanes.
结论:
- 该研究报告了第一个可分离的14组元素的silyl和germyl激素,挑战了以前关于稳定性要求的概念.
- 平面几何和根中心的sp2杂交是这些新型物种的关键特征.
- 这些基因作为有价值的合成子,通过化产生新的有机和有机化合物.
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