控制碳中心和氧化物激素之间的交叉反应的 entropy
J Sobek1, R Martschke, H Fischer
1Physikalisch-Chemisches Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
Journal of the American Chemical Society
|July 18, 2001
概括
这项研究量化了碳基和氧化物之间的交叉合反应速率. 反应速度取决于分子结构,通常表现出非Arrhenius温度行为.
科学领域:
- 有机化学 有机化学
- 化学动力学 化学动力学
背景情况:
- 氧化物是有机合成中的关键中间体.
- 了解激进反应对于开发新的合成方法至关重要.
研究的目的:
- 确定以碳为中心的基和氧化物交叉合反应的绝对速率常数.
- 为了研究这些反应的温度依赖性.
主要方法:
- 动力吸收光谱法用于测量液相反应速率.
- 使用了一系列以碳为中心的激素和氧化物.
主要成果:
- 速率常数显著变化 (<2 x 10^5到2.3 x 10^9 M^-1 s^-1),受反应物结构的影响.
- 在许多情况下,观察到非Arrhenius温度依赖.
- 发现合速率常数与氧胺裂解速率之间存在相关性.
结论:
- 观察到的动力学表明无障碍,单步反应机制.
- 一个大的负项很可能主导激活的自由能量.
- 这些发现提供了有关激进交叉合反应的因素的见解.
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