通过电子诱导键激活,共相堆叠的多化物中的分子内C-H/C-D交换
Cheryl D Stevenson1, Matthew K Kiesewetter, Richard C Reiter
1Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160, USA. cdsteve@ilstu.edu
Journal of the American Chemical Society
|April 14, 2005
概括
聚烯的单电子还原产生局部化在外部烯单元上的离子基. 这些基因不成比例,形成二离子,使分子内在低温下能够交换.
科学领域:
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 多化物是合聚合物,在有机电子学中具有潜在的应用.
- 了解它们的电子结构和反应性对于材料设计至关重要.
研究的目的:
- 为了研究一个电子减少的多烯的电子结构和反应性.
- 阐明离子基形成的机制和随后的反应.
主要方法:
- 电子磁共振 (EPR) 光谱在六甲基酸中.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 聚烯的单电子还原产生离子基,其不配对的电子定位在外在的烯单元上.
- 离子基不成比例地形成与非经典pz重叠的二磁离子.
- 内部分子交换发生在低至90K的温度下,由于C-H键激活和p-轨道重叠.
结论:
- 减少的多烯的电子结构促进了独特的反应性.
- 低温的分子内交换是这些二离子体的一个关键特征.
相关概念视频
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The double bond in a simple, unconjugated alkene is a region of high electron density that can act as a weak base or a nucleophile. The filled π orbital (HOMO) of the double bond can interact with the empty LUMO of an electrophile. A bonding interaction occurs when the electrophile attacks between the two carbons; the electrophile then accepts a pair of electrons from the π bond and undergoes addition across the double bond, yielding a single product.
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01:17Thermal Electrocyclic Reactions: Stereochemistry
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