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双乙烯的光和温度控制:一个磁性双乙烯
Paolo Costa1, Thomas Lohmiller1,2, Iris Trosien1
1Lehrstuhl für Organische Chemie II, Ruhr-Universität Bochum , 44780 Bochum, Germany.
Journal of the American Chemical Society
|January 16, 2016
概括
双 (p-methoxyphenyl) 碳是第一个在3K时分离出来的碳.光控制碳
科学领域:
- 有机化学
- 摄影化学
- 光谱学
背景情况:
- 碳是有机合成中至关重要的高反应性中间体.
- 了解碳旋状态 (单环和三环) 是控制其反应性的关键.
- 在低温下将碳分离到特定的自旋状态是一个很大的挑战.
研究的目的:
- 在冷却温度下研究 bis (p-methoxyphenyl) 碳单体和三体状态的分离和相互转换.
- 探索光辐射和温度对碳的自旋状态的影响.
- 评估光控制的碳旋状态的潜在应用.
主要方法:
- 在3K的阿尔贡矩阵和MTHF玻璃中隔离bis (p-methoxyphenyl) 碳素.
- 使用IR,UV-vis,X频段EPR,W频段EPR和Q频段ENDOR进行光谱表征.
- 使用紫外线 (365 nm) 和可见光 (450 nm) 的光化学操纵和热.
主要成果:
- 在单体和三体状态中成功分离了bis (p- methoxyphenyl) 碳,在3K时无限期共存.
- 紫外线照射有利于三重状态,而可见光则有利于单重状态.
- 热化将三合体转化为单合体,在冷却后是不可逆转的过程.
结论:
- 可以通过光波长和矩阵温度选择性地控制bis ((p-methoxyphenyl) carbene的自旋状态.
- 这种对碳旋状态的光诱导控制为信息存储和聚合的应用提供了潜力.
- 这些发现表明一种用于先进材料应用的新方法来处理反应性中间体.
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