一个不寻常的P-P双键通过终端PO复合体的-维蒂格转换形成
Nicholas A Piro1, Christopher C Cummins
1Department of Chemistry, 77 Massachusetts Avenue, Room 6-435, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|June 10, 2009
概括
在氧化物复合体和酸复合体之间的一种新的O-for-PSiR3转化反应产生了一个独特的二二复合体. 这个复合体表现出不寻常的结合,并通过双分子通路进行降解.
科学领域:
- 有机金属化学 有机金属化学
- 无机合成 无机合成
- 协调化学 协调化学
背景情况:
- 含的配体在有机金属化学中至关重要,影响金属中心的反应性和电子性质.
- 转化反应为合成具有独特连接体框架的新型金属复合体提供了一条强大的途径.
- 了解低坐标物种的结合和反应性对于推进无机化学至关重要.
研究的目的:
- 为了研究终端氧化物复合物和酸复合物之间的O-for-PSiR3转化反应.
- 描述由此产生的二二复合物,并阐明其电子结构和结合.
- 探索新型二二复合物的反应和降解途径.
主要方法:
- 合成氧化和氧化复合物.
- O-for-PSiR3转化反应以形成oxoniobium和diphosphenido复合体.
- 用X射线结晶学测定二二复合物的结构.
- 密度函数理论 (DFT) 计算以支持结合特征.
- 涉及diphosphenido复合物和trifenylphosphine的平衡研究.
主要成果:
- 对PSiR3的O转化成功产生了一个oxoniobium复合物和一个新的二二化合物复合物, (iPr3SiPPMo(N[(tBu) ]Ar) 3).
- X射线结晶学和DFT计算揭示了一种独特的"单曲"二二联体,作为d2金属中心的3e-捐赠体.
- 通过双分子通路,二二化合物复合物随着时间的推移而降解,形成终端合物复合物作为稳定的离开组.
- 在diphosphenido复合物,PPh3和phosphinidene转移产物之间建立了平衡.
结论:
- 这项研究展示了一种新的合成途径,以获得具有不寻常结合方式的独特二二化合物复合物.
- 在有机金属化学中,特征化的二二化合物复合体代表了一类新的低坐标联体.
- 观察到的降解途径凸显了这些新型复合物的动态性和反应性.
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