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Synthesis of a Water-soluble Metal–Organic Complex Array
Published on: October 8, 2016
溶剂效应:过渡金属基的重组是否存在旋转障碍?
John D Harris1, Alan B Oelkers, David R Tyler
1Department of Chemistry, University of Oregon, Eugene, Oregon 97403, USA.
Journal of the American Chemical Society
|April 24, 2007
概括
这项研究没有发现过渡金属根基对重组的旋转障碍的证据. 重原子探测器没有影响重组效率,这表明直接旋转交叉并不是限制因素.
科学领域:
- 无机化学 无机化学
- 摄影化学的使用.
- 物理化学 物理化学
背景情况:
- 激素重组在化学反应中至关重要.
- 了解对重组的旋转效应是过渡金属化学的关键.
- 激素对是光化学中的重要中间体.
研究的目的:
- 为了调查第一和第二排过渡金属中心激素中对重组的自旋障碍的存在.
- 为了确定旋转状态是否影响激素对的重组效率.
- 探索重原子效应在调节激素重组中的作用.
主要方法:
- 五秒探测器短暂吸收光谱法,直接测量激素对 (FcP) 重组动力学.
- 稳态方法使用量子产量和溶剂粘度来确定FcP.
- 双核金属碳化合物复合物 (Cp'2Mo2(CO) 6,Cp'2Fe2(CO) 4和二化物复合物 (Cp*2TiCl2) 的光解产生基因对.
- 使用重原子探头 (p-二二,二) 来评估旋转效应.
主要成果:
- 在任何使用探针或稳定状态方法的研究激素对中都没有检测到可观察到的重原子效应.
- 通过光化学生成的根子对的重组效率在 heavy atom 探针的存在和不存在下进行了测量.
- 在不同的过渡金属 (Mo,Fe,Ti) 和实验方法中获得了一致的结果.
结论:
- 由于没有可观测的重原子效应,因此得出结论,对于这些以过渡金属为中心的激素来说,再组合没有显著的自旋障碍.
- 旋转交叉并不是这些激进子对的重组过程中的速度限制步骤.
- 这一发现对理解涉及过渡金属基的反应机制有意义.
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