暴露的氧:一种开的单片物,在溶液中具有皮秒寿命,但在循环butanedione前体的晶体中持久
Gregory Kuzmanich1, Fabian Spänig, Chao-Kuan Tsai
1Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1559, USA.
Journal of the American Chemical Society
|February 9, 2011
概括
一个环二的光诱导脱碳化产生了一个稳定的,深蓝色的氧二基. 这种动态稳定物种表现出独特的电子特性,通过先进的光谱和计算方法证实了这一点.
科学领域:
- 摄影化学的使用.
- 有机化学 有机化学
- 量子化学 是一个量子化学.
背景情况:
- 环butanedione衍生物是反应性中间体的前体.
- 光诱导反应为新型分子物种提供了途径.
- 了解二基稳定性对于反应机制至关重要.
研究的目的:
- 为了研究2,4-bis(spirocyclohexyl) -1,3-cyclobutanedione的光诱导脱碳化.
- 为了描述在固态中形成的过渡物种.
- 为了阐明由此产生的氧二基的电子结构和稳定性.
主要方法:
- 循环butanedione的固态光解.
- 光谱分析 (UV-Vis,等等) 进行. ) 的情况.
- 计算化学:CASSCF和合集群计算.
主要成果:
- 形成一个深蓝色的瞬态 (λmax = 550 nm) 的半衰期为42分钟,在298 K.
- 作为一种动力稳定氧类物种的过渡物体的识别.
- 谱学和计算证据支持一个开放单片二基结构.
结论:
- 光诱导脱碳化提供了进入稳定的氧二基的途径.
- 观察到的稳定性归因于动力稳定.
- 先进的计算方法准确地预测了二极根的电子光谱.
相关概念视频
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01:12Cycloaddition Reactions: MO Requirements for Photochemical Activation
Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.
01:26Photochemical Electrocyclic Reactions: Stereochemistry
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01:16Cycloaddition Reactions: MO Requirements for Thermal Activation
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01:16Cycloaddition Reactions: Overview
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