减小应变的多循环:一个烯离子能承受多少应变?
Ivan Aprahamian1, Graham J Bodwell, Jim J Fleming
1Department of Organic Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
Journal of the American Chemical Society
|May 27, 2004
概括
在[n](2,7) 聚烯中压力决定了还原产品. 较短的带产生二分化和西格玛键的形成,而较长的带导致二离子物种和溶剂裂变.
科学领域:
- 有机化学 有机化学
- 超分子化学 超分子化学
背景情况:
- 烯是带有连接桥梁的多环芳化合物.
- 了解它们的反应性对于设计新型有机材料至关重要.
研究的目的:
- 为了研究绳索长度对[n](2,7) pyrenophanes的还原性行为的影响.
- 阐明金属还原过程中形成的反应通路和产品.
主要方法:
- 使用或金属减少[n](2,7) 烯 (n=7-10) .
- 使用光谱技术分析减少产品.
主要成果:
- 较短的绳索 ([7]-和 [2]metacyclo[2]-) 导致了还原性二元化和分子内西格玛键的形成.
- [8](2,7) 烯仅经过了减小的二元化.
- 较长的带 ([9]-和 [10](2,7) 聚烯) 形成了二离子反芳香物种,导致溶剂裂变.
结论:
- 带应变是控制烯的减少途径的关键因素.
- 观察到新的反应途径,包括西格玛键的形成和溶剂裂变.
- 较长束的pyrenophanes的还原行为类似于pyrene本身.
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