循环环-eta2-ynylzwitterionic基:一个有机金属的证据
Steven J Peters1, Matthew R Turk, Matthew K Kiesewetter
1Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160, USA.
Journal of the American Chemical Society
|October 14, 2005
概括
研究人员使用低温脱化和金属减少产生了 [8]annulyne离子基. 和还原剂由于阴离子-p-轨道相互作用,产生了巨大的金属裂变,与或不同.
科学领域:
- 有机金属化学 有机金属化学
- 电子偏磁共振 (EPR) 光谱法 电子偏磁共振 (EPR) 光谱法
- 芳香性研究 芳香性研究
背景情况:
- [8]annulyne是一种非替代性,化环系统,与芳香性研究有关.
- 了解金属离子与基离子相互作用对于反应机制至关重要.
研究的目的:
- 为了合成和描述 [8]annulyne. 的离子基.
- 调查金属对 EPR 频谱的影响.
- 探索皇冠乙烯对离子配对和基质结构的影响.
主要方法:
- 低温脱氧化氧化.bromocyclooctatetraene的低温脱氧化.
- 在四水富中性金属的减少.
- 电子偏磁共振 (EPR) 光谱在-120°C.
- 添加18-皇冠-6来研究离子配对.
主要成果:
- 产生 [8]annulyne 离子基 (C8H6*-).
- 使用K和Cs还原剂观察异常大的金属裂变 (aM),归因于与基 p 轨道的阳离子相互作用.
- 由于离子半径较小,没有观察到Na或Li的显著金属裂变.
- 添加18-crown-6诱导了离子配对和zwitterionic基因物种之间的平衡,具有明显的EPR信号和金属裂变.
结论:
- 金属离子的大小显著影响其与 [8]annulyne 离子基的相互作用.
- 在基因部分内,特定的子-p-轨道相互作用对观察到的大型金属裂变负责.
- 18-皇冠-6 破坏了正常的离子配对,导致有机金属zwitterions的形成,并影响观察到的EPR光谱.
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