超快UV/IR探头研究线性,循环和化中C-H激活的研究
Matthew C Asplund1, Preston T Snee, Jake S Yeston
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|August 29, 2002
概括
研究了复合物的光化学C-H键激活. 基质结构影响激活,芳香C-H键通过涉及溶解中间体的独特途径进行.
科学领域:
- 有机金属化学 有机金属化学
- 摄影化学的使用.
- 反应动力学 反应动力学
背景情况:
- 复合物是有机合成中的重要催化剂.
- 了解C-H激活机制对于开发新的催化过程至关重要.
- 光化学激活提供了独特的反应途径.
研究的目的:
- 为了研究eta(3) -TpRh(CO) ((2) 和CpRh(CO) ((2) 复合物的光化学C-H激活反应.
- 阐明碳化合物基质结构对C-H键激活动态的影响.
- 为了比较eta(3) -TpRh(CO) ((2) 和CpRh(CO) ((2) 的反应机制.
主要方法:
- 五秒到微秒的时间分辨率光谱学.
- 研究各种线性,循环和芳香碳化合物溶剂中的反应.
- 对eta{3}-TpRh{CO}{2}和CpRh{CO}{2}复合物的比较分析.
主要成果:
- 碳化合物基质结构决定了最终的C-H键激活步骤,有利于主要的C-H位点.
- 芳香C-H激活通过与西格玛和pi-solvated中间体的平行通道进行.
- 在CpRh ((CO) ((2) 中的环聚二烯连接体并不直接影响反应动态,与eta ((3) -TpRh ((CO) ((2) 不同.
结论:
- 基质C-H键可访问性和电子因素是光化学C-H激活的关键决定因素.
- 由于连接物效应,eta(3) -TpRh(CO) ((2) 的反应机制与CpRh(CO) ((2) 的反应机制显著不同.
- 这些发现提供了对选择性CH功能化策略的见解.
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